add use-vendored-config feature

Without that, I got the following error from cargo:
```
error: target `demo` in package `lvgl` requires the features: `alloc`
Consider enabling them by passing, e.g., `--features="alloc"`
```

.github/workflows/rust.yml

@@ -0,0 +1,33 @@
+name: Rust
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+env:
+  CARGO_TERM_COLOR: always
+  DEP_LV_CONFIG_PATH: /home/runner/work/lvgl-rs/lvgl-rs/examples/include
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Update APT
+        run: sudo apt-get update
+
+      - name: Install SDL2
+        run: sudo apt install libsdl2-dev libsdl2-2.0-0
+
+      - uses: actions/checkout@v2
+        with:
+          submodules: true
+
+      - name: Build
+        run: cargo build --verbose
+
+      - name: Run tests
+        run: cargo test --verbose

.gitignore

@@ -12,4 +12,3 @@ Cargo.lock
 examples/demo/target/
 lvgl-sys/target/
 lvgl/target/
-lvgl-sys/src/bindings.rs

.gitmodules

@@ -1,3 +1,3 @@
 [submodule "lvgl-sys/vendor/lvgl"]
 	path = lvgl-sys/vendor/lvgl
-	url = https://github.com/littlevgl/lvgl.git
+	url = https://github.com/lvgl/lvgl.git

CODE_OF_CONDUCT.md

@@ -0,0 +1,76 @@
+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to making participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, sex characteristics, gender identity and expression,
+level of experience, education, socio-economic status, nationality, personal
+appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or
+ advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+ address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+ professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies both within project spaces and in public spaces
+when an individual is representing the project or its community. Examples of
+representing a project or community include using an official project e-mail
+address, posting via an official social media account, or acting as an appointed
+representative at an online or offline event. Representation of a project may be
+further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at lvgl-rs.coc@caric.io. All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html
+
+[homepage]: https://www.contributor-covenant.org
+
+For answers to common questions about this code of conduct, see
+https://www.contributor-covenant.org/faq

Cargo.toml

@@ -1,6 +1,6 @@
 [workspace]
 members = [
     "lvgl",
+    "lvgl-codegen",
     "lvgl-sys",
-    "examples/demo",
 ]

README.md

@@ -1,24 +1,41 @@
-<h1 align="center"> LittlevGL - Open-source Embedded GUI Library in Rust</h1>
+[![SWUbanner](https://raw.githubusercontent.com/vshymanskyy/StandWithUkraine/main/banner2-direct.svg)](https://github.com/vshymanskyy/StandWithUkraine/blob/main/docs/README.md)
 
-![Original LittlevGL demo image](lv_demo.png)
+<h1 align="center"> LVGL - Open-source Embedded GUI Library in Rust</h1>
+
+![Original LVGL demo image](lv_demo.png)
 
 <p align="center">
-LittlevGL provides everything you need to create a Graphical User Interface (GUI) on embedded systems with easy-to-use graphical elements, beautiful visual effects and low memory footprint. 
+LVGL provides everything you need to create a Graphical User Interface (GUI) on embedded systems with easy-to-use graphical elements, beautiful visual effects and low memory footprint. 
 </p>
 <p align="center">
-LittlevGL is compatible with <samp>#![no_std]</samp> environments by default.
+LVGL is compatible with <samp>#![no_std]</samp> environments by default.
 </p>
 
 <h4 align="center">
-<a href="https://lvgl.io/">Official LittlevGL Website </a> &middot; 
+<a href="https://github.com/rafaelcaricio/lvgl-rs-wasm">Rust to WASM demo</a> &middot;
+<a href="https://lvgl.io/">Official LVGL Website </a> &middot;
 <a href="https://github.com/littlevgl/lvgl">C library repository</a> &middot;
-<a href="https://lvgl.io/demos">Live demo</a>
+<a href="https://lvgl.io/demos">Official live demos</a>
 </h4>
 
 ---
 
 ![Rust bindings usage demo code.](demo.png)
 
+## System Build Dependencies
+
+In order to build the `lvgl` project you will need the following system dependencies to be installed:
+
+```
+$ sudo apt install build-essential llvm clang
+```
+
+If you want to build the examples, then you will need to install SDL2 as well.
+
+```
+$ sudo apt install libsdl2-dev
+```
+
 ## Usage
 
 Edit your `Cargo.toml` file dependencies with:
@@ -28,7 +45,7 @@ $ cargo add lvgl
 
 The build requires the environment variable bellow to be set:
 
-- `DEP_LV_CONFIG_PATH`: Path to the directory containing the `lv_conf.h` header file used for configuration of LittlevGL library.
+- `DEP_LV_CONFIG_PATH`: Path to the directory containing the `lv_conf.h` header file used for configuration of LVGL library.
 
 We recommend the `lv_conf.h` file to be in your project's root directory. If so, the command to build your project would be:
 ```shell script
@@ -44,14 +61,57 @@ for `no_std`, so we need to use a workaround to build "lvgl-rs". The mainstrem i
 ```shell
 $ DEP_LV_CONFIG_PATH=`pwd` cargo build -Zfeatures=build_dep
 ```
+### LVGL Global Allocator
 
-#### Requirements / Limitations
-
-LittlevGL C libary do allocate memory dynamically and we need to allocate memory on the heap in the Rust side as well
-([`Box`](https://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html)).
-That is required, so we can safely provide Rust pointers through FFI. For that reason, we do require
-[`alloc`](https://doc.rust-lang.org/alloc/) module to be available.
+A [global allocator](https://doc.rust-lang.org/std/alloc/trait.GlobalAlloc.html) for Rust leveraging the
+[LVGL memory allocator](https://github.com/lvgl/lvgl/blob/master/src/misc/lv_mem.h) is provided, but not enabled 
+by default. Can be enabled by the feature `lvgl_alloc`. This will make all dynamic memory to be allocated by LVGL 
+internal memory manager.
 
 ## Running the demo
 
-[This project contains an example that can run in a desktop simulator.](./examples/demo)
+**Hint for macOS users**: Before you run the demos you need to make sure you have [libsdl](https://www.libsdl.org)
+installed on your machine. To install it, use HomeBrew:
+
+```shell
+$ brew install sdl2
+```
+
+[This project contains examples that can run in a desktop simulator.](./examples)
+
+First, make sure to pull `lvgl-rs` submodules:
+```shell
+$ git submodule init
+$ git submodule update 
+```
+
+Then run the `demo` example:
+
+```shell
+$ DEP_LV_CONFIG_PATH=`pwd`/examples/include cargo run --example demo --features="alloc"
+```
+
+## Feature Support
+
+The bindings are still in development. There are many features of LVGL that needs to be exposed by `lvgl-rs`. In
+this section you can check what is implemented at the moment.
+
+### Features
+
+List of LVGL features that impacts the library usage in general.
+- [x] Displays: We use [`embedded_graphics`](https://docs.rs/embedded-graphics/0.6.2/embedded_graphics/) library to
+      draw to the display. You can use `lvgl-rs` with any of the
+      [`embedded_graphics` supported displays](https://docs.rs/embedded-graphics/0.6.2/embedded_graphics/#supported-displays).
+- [x] Events: You can listen and trigger events in widget objects.
+- [x] Styles: You can set styles in any exposed object. We are still missing the possibility of defining global base styles.
+- [ ] Input Devices
+- [ ] Fonts
+- [ ] Images
+- [ ] File system
+- [ ] Animations
+- [ ] Tasks
+
+### Widgets
+
+Widgets currently implemented might have some missing features. If the widget you want to use is not exposed or
+is missing a feature you want to make use, please send a Pull Request or open an issue.

examples/README.md

@@ -0,0 +1,8 @@
+## Examples of how to use various  `lvgl-rs` widgets/components
+
+All examples can be executed using:
+```shell
+cargo run --example <name>
+```
+
+The `DEP_LV_CONFIG_PATH` environment variable is necessary, as explained in the [README](../README.md).

examples/arc.rs

@@ -0,0 +1,106 @@
+use cstr_core::CString;
+use embedded_graphics::pixelcolor::Rgb565;
+use embedded_graphics::prelude::*;
+use embedded_graphics_simulator::{
+    OutputSettingsBuilder, SimulatorDisplay, SimulatorEvent, Window,
+};
+use lvgl::style::Style;
+use lvgl::widgets::{Arc, Label, LabelAlign};
+use lvgl::{self, Align, Color, Part, State, UI};
+use lvgl::{LvError, Widget};
+use lvgl_sys;
+use std::time::Instant;
+
+fn mem_info() -> lvgl_sys::lv_mem_monitor_t {
+    let mut info = lvgl_sys::lv_mem_monitor_t {
+        total_size: 0,
+        free_cnt: 0,
+        free_size: 0,
+        free_biggest_size: 0,
+        used_cnt: 0,
+        max_used: 0,
+        used_pct: 0,
+        frag_pct: 0,
+    };
+    unsafe {
+        lvgl_sys::lv_mem_monitor(&mut info as *mut _);
+    }
+    info
+}
+
+fn main() -> Result<(), LvError> {
+    println!("meminfo init: {:?}", mem_info());
+    run_arc_demo()?;
+    println!("meminfo end: {:?}", mem_info());
+    Ok(())
+}
+
+fn run_arc_demo() -> Result<(), LvError> {
+    let display: SimulatorDisplay<Rgb565> = SimulatorDisplay::new(Size::new(
+        lvgl_sys::LV_HOR_RES_MAX,
+        lvgl_sys::LV_VER_RES_MAX,
+    ));
+
+    let output_settings = OutputSettingsBuilder::new().scale(2).build();
+    let mut window = Window::new("Arc Example", &output_settings);
+
+    let mut ui = UI::init()?;
+
+    // Implement and register your display:
+    ui.disp_drv_register(display)?;
+
+    // Create screen and widgets
+    let mut screen = ui.scr_act()?;
+
+    let mut screen_style = Style::default();
+    screen_style.set_bg_color(State::DEFAULT, Color::from_rgb((255, 255, 255)));
+    screen_style.set_radius(State::DEFAULT, 0);
+    screen.add_style(Part::Main, screen_style)?;
+
+    // Create the arc object
+    let mut arc = Arc::new(&mut screen)?;
+    arc.set_size(150, 150)?;
+    arc.set_align(&mut screen, Align::Center, 0, 10)?;
+    arc.set_start_angle(135)?;
+    arc.set_end_angle(135)?;
+
+    let mut loading_lbl = Label::new(&mut screen)?;
+    loading_lbl.set_text(CString::new("Loading...").unwrap().as_c_str())?;
+    loading_lbl.set_align(&mut arc, Align::OutTopMid, 0, -10)?;
+    loading_lbl.set_label_align(LabelAlign::Center)?;
+
+    let mut loading_style = Style::default();
+    loading_style.set_text_color(State::DEFAULT, Color::from_rgb((0, 0, 0)));
+    loading_lbl.add_style(Part::Main, loading_style)?;
+
+    let mut angle = 0;
+    let mut forward = true;
+    let mut i = 0;
+
+    let mut loop_started = Instant::now();
+    'running: loop {
+        if i > 270 {
+            forward = if forward { false } else { true };
+            i = 1;
+            println!("meminfo running: {:?}", mem_info());
+        }
+        angle = if forward { angle + 1 } else { angle - 1 };
+        arc.set_end_angle(angle + 135)?;
+        i += 1;
+
+        ui.task_handler();
+        window.update(ui.get_display_ref().unwrap());
+
+        for event in window.events() {
+            match event {
+                SimulatorEvent::Quit => break 'running,
+                _ => {}
+            }
+        }
+
+        ui.tick_inc(loop_started.elapsed());
+        loop_started = Instant::now();
+    }
+
+    Ok(())
+}

examples/bar.rs

@@ -0,0 +1,83 @@
+use cstr_core::CString;
+use embedded_graphics::pixelcolor::Rgb565;
+use embedded_graphics::prelude::*;
+use embedded_graphics_simulator::{
+    OutputSettingsBuilder, SimulatorDisplay, SimulatorEvent, Window,
+};
+use lvgl::style::Style;
+use lvgl::widgets::{Bar, Label, LabelAlign};
+use lvgl::{self, Align, Animation, Color, Event, LvError, Part, State, Widget, UI};
+use lvgl_sys;
+use std::time::Instant;
+
+fn main() -> Result<(), LvError> {
+    let display: SimulatorDisplay<Rgb565> = SimulatorDisplay::new(Size::new(
+        lvgl_sys::LV_HOR_RES_MAX,
+        lvgl_sys::LV_VER_RES_MAX,
+    ));
+
+    let output_settings = OutputSettingsBuilder::new().scale(2).build();
+    let mut window = Window::new("Bar Example", &output_settings);
+
+    let mut ui = UI::init()?;
+
+    // Implement and register your display:
+    ui.disp_drv_register(display).unwrap();
+
+    // Create screen and widgets
+    let mut screen = ui.scr_act()?;
+
+    let mut screen_style = Style::default();
+    screen_style.set_bg_color(State::DEFAULT, Color::from_rgb((255, 255, 255)));
+    screen_style.set_radius(State::DEFAULT, 0);
+    screen.add_style(Part::Main, screen_style)?;
+
+    // Create the bar object
+    let mut bar = Bar::new(&mut screen)?;
+    bar.set_size(175, 20)?;
+    bar.set_align(&mut screen, Align::Center, 0, 10)?;
+    bar.set_range(0, 100)?;
+    bar.on_event(|_b, _e| {
+        println!("Completed!");
+    })?;
+
+    // // Set the indicator style for the bar object
+    let mut ind_style = Style::default();
+    ind_style.set_bg_color(State::DEFAULT, Color::from_rgb((100, 245, 100)));
+    bar.add_style(Part::All, ind_style)?;
+
+    let mut loading_lbl = Label::new(&mut screen)?;
+    loading_lbl.set_text(CString::new("Loading...").unwrap().as_c_str())?;
+    loading_lbl.set_align(&mut bar, Align::OutTopMid, 0, -10)?;
+    loading_lbl.set_label_align(LabelAlign::Center)?;
+
+    let mut loading_style = Style::default();
+    loading_style.set_text_color(State::DEFAULT, Color::from_rgb((0, 0, 0)));
+    loading_lbl.add_style(Part::Main, loading_style)?;
+
+    let mut i = 0;
+    let mut loop_started = Instant::now();
+    'running: loop {
+        if i > 100 {
+            i = 0;
+            ui.event_send(&mut bar, Event::Clicked)?;
+        }
+        bar.set_value(i, Animation::ON)?;
+        i += 1;
+
+        ui.task_handler();
+        window.update(ui.get_display_ref().unwrap());
+
+        for event in window.events() {
+            match event {
+                SimulatorEvent::Quit => break 'running,
+                _ => {}
+            }
+        }
+
+        ui.tick_inc(loop_started.elapsed());
+        loop_started = Instant::now();
+    }
+
+    Ok(())
+}

examples/button_click.rs

@@ -0,0 +1,82 @@
+use cstr_core::CString;
+use embedded_graphics::pixelcolor::Rgb565;
+use embedded_graphics::prelude::*;
+use embedded_graphics_simulator::{
+    OutputSettingsBuilder, SimulatorDisplay, SimulatorEvent, Window,
+};
+use lvgl::style::Style;
+use lvgl::widgets::{Btn, Label};
+use lvgl::{self, Align, Color, Event, LvError, Part, State, Widget, UI};
+use lvgl_sys;
+use std::time::Instant;
+
+fn main() -> Result<(), LvError> {
+    let display: SimulatorDisplay<Rgb565> = SimulatorDisplay::new(Size::new(
+        lvgl_sys::LV_HOR_RES_MAX,
+        lvgl_sys::LV_VER_RES_MAX,
+    ));
+
+    let output_settings = OutputSettingsBuilder::new().scale(2).build();
+    let mut window = Window::new("Bar Example", &output_settings);
+
+    let mut ui = UI::init()?;
+
+    // Implement and register your display:
+    ui.disp_drv_register(display)?;
+
+    // Create screen and widgets
+    let mut screen = ui.scr_act()?;
+
+    let mut screen_style = Style::default();
+    screen_style.set_bg_color(State::DEFAULT, Color::from_rgb((0, 0, 0)));
+    screen.add_style(Part::Main, screen_style)?;
+
+    // Create the button
+    let mut button = Btn::new(&mut screen)?;
+    button.set_align(&mut screen, Align::InLeftMid, 30, 0)?;
+    button.set_size(180, 80)?;
+    let mut btn_lbl = Label::new(&mut button)?;
+    btn_lbl.set_text(CString::new("Click me!").unwrap().as_c_str())?;
+
+    let mut btn_state = false;
+    button.on_event(|mut btn, event| {
+        if let lvgl::Event::Clicked = event {
+            if btn_state {
+                let nt = CString::new("Click me!").unwrap();
+                btn_lbl.set_text(nt.as_c_str()).unwrap();
+            } else {
+                let nt = CString::new("Clicked!").unwrap();
+                btn_lbl.set_text(nt.as_c_str()).unwrap();
+            }
+            btn_state = !btn_state;
+            println!("Clicked! Inner..");
+            btn.toggle().unwrap();
+        }
+    })?;
+
+    let mut loop_started = Instant::now();
+    'running: loop {
+        ui.task_handler();
+        window.update(ui.get_display_ref().unwrap());
+
+        for event in window.events() {
+            match event {
+                SimulatorEvent::MouseButtonUp {
+                    mouse_btn: _,
+                    point,
+                } => {
+                    println!("Clicked on: {:?}", point);
+                    // Send a event to the button directly
+                    ui.event_send(&mut button, Event::Clicked)?;
+                }
+                SimulatorEvent::Quit => break 'running,
+                _ => {}
+            }
+        }
+
+        ui.tick_inc(loop_started.elapsed());
+        loop_started = Instant::now();
+    }
+
+    Ok(())
+}

examples/demo.rs

@@ -0,0 +1,101 @@
+use cstr_core::CString;
+use embedded_graphics::pixelcolor::Rgb565;
+use embedded_graphics::prelude::*;
+use embedded_graphics_simulator::{
+    OutputSettingsBuilder, SimulatorDisplay, SimulatorEvent, Window,
+};
+use lvgl;
+use lvgl::style::Style;
+use lvgl::widgets::{Label, LabelAlign};
+use lvgl::{Align, Color, LvError, Part, State, Widget, UI};
+use lvgl_sys;
+use std::thread::sleep;
+use std::time::{Duration, Instant};
+
+fn main() -> Result<(), LvError> {
+    let display: SimulatorDisplay<Rgb565> = SimulatorDisplay::new(Size::new(
+        lvgl_sys::LV_HOR_RES_MAX,
+        lvgl_sys::LV_VER_RES_MAX,
+    ));
+
+    let output_settings = OutputSettingsBuilder::new().scale(2).build();
+    let mut window = Window::new("PineTime", &output_settings);
+
+    let mut ui = UI::init()?;
+
+    // Implement and register your display:
+    ui.disp_drv_register(display).unwrap();
+
+    // Create screen and widgets
+    let mut screen = ui.scr_act()?;
+
+    let mut screen_style = Style::default();
+    screen_style.set_bg_color(State::DEFAULT, Color::from_rgb((0, 0, 0)));
+    screen_style.set_radius(State::DEFAULT, 0);
+    screen.add_style(Part::Main, screen_style)?;
+
+    let mut time = Label::new(&mut screen)?;
+    let mut style_time = Style::default();
+    //style_time.set_text_font(font_noto_sans_numeric_28);
+    style_time.set_text_color(State::DEFAULT, Color::from_rgb((255, 255, 255)));
+    time.add_style(Part::Main, style_time)?;
+    time.set_align(&mut screen, Align::Center, 0, 0)?;
+    time.set_text(CString::new("20:46").unwrap().as_c_str())?;
+    time.set_width(240)?;
+    time.set_height(240)?;
+
+    let mut bt = Label::new(&mut screen)?;
+    bt.set_width(50)?;
+    bt.set_height(80)?;
+    bt.set_recolor(true)?;
+    bt.set_text(CString::new("#5794f2 \u{F293}#").unwrap().as_c_str())?;
+    bt.set_label_align(LabelAlign::Left)?;
+    bt.set_align(&mut screen, Align::InTopLeft, 0, 0)?;
+
+    let mut power = Label::new(&mut screen)?;
+    power.set_recolor(true)?;
+    power.set_width(80)?;
+    power.set_height(20)?;
+    power.set_text(CString::new("#fade2a 20%#").unwrap().as_c_str())?;
+    power.set_label_align(LabelAlign::Right)?;
+    power.set_align(&mut screen, Align::InTopRight, 0, 0)?;
+
+    let mut i = 0;
+    let mut loop_started = Instant::now();
+    'running: loop {
+        if i > 59 {
+            i = 0;
+        }
+        let val = CString::new(format!("21:{:02}", i)).unwrap();
+        time.set_text(&val)?;
+        i = 1 + i;
+
+        ui.task_handler();
+        window.update(ui.get_display_ref().unwrap());
+
+        for event in window.events() {
+            match event {
+                SimulatorEvent::Quit => break 'running,
+                _ => {}
+            }
+        }
+        sleep(Duration::from_secs(1));
+
+        ui.tick_inc(loop_started.elapsed());
+        loop_started = Instant::now();
+    }
+
+    Ok(())
+}
+
+// Reference to native font for LVGL, defined in the file: "fonts_noto_sans_numeric_80.c"
+// TODO: Create a macro for defining a safe wrapper for fonts.
+// Maybe sometihng like:
+//
+// font_declare! {
+//     NotoSansNumeric80 = noto_sans_numeric_80;
+// };
+//
+extern "C" {
+    pub static mut noto_sans_numeric_80: lvgl_sys::lv_font_t;
+}

examples/demo/Cargo.toml

@@ -1,14 +0,0 @@
-[package]
-name = "demo"
-version = "0.1.0"
-authors = ["Rafael Caricio <crates@caric.io>"]
-edition = "2018"
-publish = false
-
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
-[dependencies]
-lvgl = { path = "../../lvgl" }
-lvgl-sys = { path = "../../lvgl-sys" }
-embedded-graphics = "0.6"
-embedded-graphics-simulator = "0.2.0"

examples/demo/README.md

@@ -1,12 +0,0 @@
-From base of the repository, install LVGL git submodule.
-
-```
-git submodule update --init
-```
-
-Run this demo:
-
-```
-cd examples/demo/
-DEP_LV_CONFIG_PATH=./include cargo run
-```

examples/demo/src/main.rs

@@ -1,123 +0,0 @@
-use embedded_graphics::pixelcolor::Rgb565;
-use embedded_graphics::prelude::*;
-use embedded_graphics_simulator::{
-    OutputSettingsBuilder, SimulatorDisplay, SimulatorEvent, Window,
-};
-use lvgl;
-use lvgl::{Object, UI};
-use lvgl_sys;
-use std::sync::{mpsc, Arc, Mutex};
-use std::thread::sleep;
-use std::time::Duration;
-
-fn main() -> Result<(), String> {
-    let mut display: SimulatorDisplay<Rgb565> = SimulatorDisplay::new(Size::new(
-        lvgl_sys::LV_HOR_RES_MAX,
-        lvgl_sys::LV_VER_RES_MAX,
-    ));
-
-    let output_settings = OutputSettingsBuilder::new().scale(2).build();
-    let mut window = Window::new("PineTime", &output_settings);
-
-    let mut ui = UI::init().unwrap();
-
-    // Implement and register your display:
-    let display_driver = lvgl::DisplayDriver::new(&mut display);
-    ui.disp_drv_register(display_driver);
-
-    // Create screen and widgets
-    let mut screen = ui.scr_act();
-
-    let font_roboto_28 = unsafe { &lvgl_sys::lv_font_roboto_28 };
-    let font_noto_sans_numeric_28 = unsafe { &noto_sans_numeric_80 };
-
-    let mut screen_style = lvgl::Style::new();
-    screen_style.set_body_main_color(lvgl::Color::from_rgb((0, 0, 0)));
-    screen_style.set_body_grad_color(lvgl::Color::from_rgb((0, 0, 0)));
-    screen_style.set_body_radius(0);
-    screen.set_style(screen_style);
-
-    let mut time = lvgl::Label::new(&mut screen);
-    let mut style_time = lvgl::Style::new();
-    style_time.set_text_font(font_noto_sans_numeric_28);
-    style_time.set_text_color(lvgl::Color::from_rgb((255, 255, 255)));
-    time.set_style(style_time);
-    time.set_align(&mut screen, lvgl::Align::InLeftMid, 20, 0);
-    time.set_text("20:46");
-    time.set_width(240);
-    time.set_height(240);
-
-    let mut bt = lvgl::Label::new(&mut screen);
-    let mut style_bt = lvgl::Style::new();
-    style_bt.set_text_font(font_roboto_28);
-    let style_power = style_bt.clone();
-    bt.set_style(style_bt);
-    bt.set_width(50);
-    bt.set_height(80);
-    bt.set_recolor(true);
-    bt.set_text("#5794f2 \u{F293}#");
-    bt.set_label_align(lvgl::LabelAlign::Left);
-    bt.set_align(&mut screen, lvgl::Align::InTopLeft, 0, 0);
-
-    let mut power = lvgl::Label::new(&mut screen);
-    power.set_style(style_power);
-    power.set_recolor(true);
-    power.set_width(80);
-    power.set_height(20);
-    power.set_text("#fade2a 20%#");
-    power.set_label_align(lvgl::LabelAlign::Right);
-    power.set_align(&mut screen, lvgl::Align::InTopRight, 0, 0);
-
-    let threaded_ui = Arc::new(Mutex::new(ui));
-
-    let (stop_ch, read_ch) = mpsc::channel();
-    let closure_ui = threaded_ui.clone();
-    let tick_thr = std::thread::spawn(move || loop {
-        let period = Duration::from_millis(250);
-        closure_ui.lock().unwrap().tick_inc(period);
-
-        sleep(period);
-        if read_ch.try_recv().is_ok() {
-            break;
-        }
-    });
-
-    let mut i = 0;
-    'running: loop {
-        if i > 59 {
-            i = 0;
-        }
-        time.set_text(format!("21:{:02}", i).as_str());
-        i = 1 + i;
-
-        sleep(Duration::from_secs(1));
-
-        threaded_ui.lock().unwrap().task_handler();
-
-        window.update(&display);
-
-        for event in window.events() {
-            match event {
-                SimulatorEvent::Quit => break 'running,
-                _ => {}
-            }
-        }
-    }
-
-    stop_ch.send(true).unwrap();
-    tick_thr.join().unwrap();
-
-    Ok(())
-}
-
-// Reference to native font for LittlevGL, defined in the file: "fonts_noto_sans_numeric_80.c"
-// TODO: Create a macro for defining a safe wrapper for fonts.
-// Maybe sometihng like:
-//
-// font_declare! {
-//     NotoSansNumeric80 = noto_sans_numeric_80;
-// };
-//
-extern "C" {
-    pub static mut noto_sans_numeric_80: lvgl_sys::lv_font_t;
-}

examples/gauge.rs

@@ -0,0 +1,89 @@
+use embedded_graphics::pixelcolor::Rgb565;
+use embedded_graphics::prelude::*;
+use embedded_graphics_simulator::{
+    OutputSettingsBuilder, SimulatorDisplay, SimulatorEvent, Window,
+};
+use lvgl::style::{Opacity, Style};
+use lvgl::widgets::Gauge;
+use lvgl::{self, Align, Color, LvError, Part, State, Widget, UI};
+use lvgl_sys;
+use std::time::Instant;
+
+fn main() -> Result<(), LvError> {
+    let display: SimulatorDisplay<Rgb565> = SimulatorDisplay::new(Size::new(
+        lvgl_sys::LV_HOR_RES_MAX,
+        lvgl_sys::LV_VER_RES_MAX,
+    ));
+
+    let output_settings = OutputSettingsBuilder::new().scale(2).build();
+    let mut window = Window::new("Gauge Example", &output_settings);
+
+    let mut ui = UI::init()?;
+
+    // Implement and register your display:
+    ui.disp_drv_register(display)?;
+
+    // Create screen and widgets
+    let mut screen = ui.scr_act()?;
+
+    let mut screen_style = Style::default();
+    screen_style.set_bg_color(State::DEFAULT, Color::from_rgb((0, 0, 0)));
+    screen.add_style(Part::Main, screen_style)?;
+
+    // Create the gauge
+    let mut gauge_style = Style::default();
+    // Set a background color and a radius
+    gauge_style.set_radius(State::DEFAULT, 5);
+    gauge_style.set_bg_opa(State::DEFAULT, Opacity::OPA_COVER);
+    gauge_style.set_bg_color(State::DEFAULT, Color::from_rgb((192, 192, 192)));
+    // Set some paddings
+    gauge_style.set_pad_inner(State::DEFAULT, 20);
+    gauge_style.set_pad_top(State::DEFAULT, 20);
+    gauge_style.set_pad_left(State::DEFAULT, 5);
+    gauge_style.set_pad_right(State::DEFAULT, 5);
+
+    gauge_style.set_scale_end_color(State::DEFAULT, Color::from_rgb((255, 0, 0)));
+    gauge_style.set_line_color(State::DEFAULT, Color::from_rgb((255, 255, 255)));
+    gauge_style.set_scale_grad_color(State::DEFAULT, Color::from_rgb((0, 0, 255)));
+    gauge_style.set_line_width(State::DEFAULT, 2);
+    gauge_style.set_scale_end_line_width(State::DEFAULT, 4);
+    gauge_style.set_scale_end_border_width(State::DEFAULT, 4);
+
+    let mut gauge = Gauge::new(&mut screen)?;
+    gauge.add_style(Part::Main, gauge_style)?;
+    gauge.set_align(&mut screen, Align::Center, 0, 0)?;
+    gauge.set_value(0, 50)?;
+
+    let mut i = 0;
+    let mut loop_started = Instant::now();
+    'running: loop {
+        gauge.set_value(0, i)?;
+
+        ui.task_handler();
+        window.update(ui.get_display_ref().unwrap());
+
+        for event in window.events() {
+            match event {
+                SimulatorEvent::MouseButtonUp {
+                    mouse_btn: _,
+                    point,
+                } => {
+                    println!("Clicked on: {:?}", point);
+                }
+                SimulatorEvent::Quit => break 'running,
+                _ => {}
+            }
+        }
+
+        if i > 99 {
+            i = 0;
+        } else {
+            i = i + 1;
+        }
+
+        ui.tick_inc(loop_started.elapsed());
+        loop_started = Instant::now();
+    }
+
+    Ok(())
+}

examples/include/lv_conf.h

@@ -0,0 +1,701 @@
+/**
+ * @file lv_conf.h
+ *
+ */
+
+/*
+ * COPY THIS FILE AS `lv_conf.h` NEXT TO the `lvgl` FOLDER
+ */
+
+#if 1 /*Set it to "1" to enable content*/
+
+#ifndef LV_CONF_H
+#define LV_CONF_H
+/* clang-format off */
+
+#include <stdint.h>
+
+/*====================
+   Graphical settings
+ *====================*/
+
+/* Maximal horizontal and vertical resolution to support by the library.*/
+#define LV_HOR_RES_MAX          (240)
+#define LV_VER_RES_MAX          (240)
+
+/* Color depth:
+ * - 1:  1 byte per pixel
+ * - 8:  RGB332
+ * - 16: RGB565
+ * - 32: ARGB8888
+ */
+#define LV_COLOR_DEPTH     16
+
+/* Swap the 2 bytes of RGB565 color.
+ * Useful if the display has a 8 bit interface (e.g. SPI)*/
+#define LV_COLOR_16_SWAP   0
+
+/* 1: Enable screen transparency.
+ * Useful for OSD or other overlapping GUIs.
+ * Requires `LV_COLOR_DEPTH = 32` colors and the screen's style should be modified: `style.body.opa = ...`*/
+#define LV_COLOR_SCREEN_TRANSP    0
+
+/*Images pixels with this color will not be drawn (with chroma keying)*/
+#define LV_COLOR_TRANSP    LV_COLOR_LIME         /*LV_COLOR_LIME: pure green*/
+
+/* Enable anti-aliasing (lines, and radiuses will be smoothed) */
+#define LV_ANTIALIAS        1
+
+/* Default display refresh period.
+ * Can be changed in the display driver (`lv_disp_drv_t`).*/
+#define LV_DISP_DEF_REFR_PERIOD      30      /*[ms]*/
+
+/* Dot Per Inch: used to initialize default sizes.
+ * E.g. a button with width = LV_DPI / 2 -> half inch wide
+ * (Not so important, you can adjust it to modify default sizes and spaces)*/
+#define LV_DPI              130     /*[px]*/
+
+/* The the real width of the display changes some default values:
+ * default object sizes, layout of examples, etc.
+ * According to the width of the display (hor. res. / dpi)
+ * the displays fall in 4 categories.
+ * The 4th is extra large which has no upper limit so not listed here
+ * The upper limit of the categories are set below in 0.1 inch unit.
+ */
+#define LV_DISP_SMALL_LIMIT  30
+#define LV_DISP_MEDIUM_LIMIT 50
+#define LV_DISP_LARGE_LIMIT  70
+
+/* Type of coordinates. Should be `int16_t` (or `int32_t` for extreme cases) */
+typedef int16_t lv_coord_t;
+
+/*=========================
+   Memory manager settings
+ *=========================*/
+
+/* LittelvGL's internal memory manager's settings.
+ * The graphical objects and other related data are stored here. */
+
+/* 1: use custom malloc/free, 0: use the built-in `lv_mem_alloc` and `lv_mem_free` */
+#define LV_MEM_CUSTOM      0
+#if LV_MEM_CUSTOM == 0
+/* Size of the memory used by `lv_mem_alloc` in bytes (>= 2kB)*/
+#  define LV_MEM_SIZE    (1048576U) // 1Mb
+
+/* Complier prefix for a big array declaration */
+#  define LV_MEM_ATTR
+
+/* Set an address for the memory pool instead of allocating it as an array.
+ * Can be in external SRAM too. */
+#  define LV_MEM_ADR          0
+
+/* Automatically defrag. on free. Defrag. means joining the adjacent free cells. */
+#  define LV_MEM_AUTO_DEFRAG  1
+#else       /*LV_MEM_CUSTOM*/
+#  define LV_MEM_CUSTOM_INCLUDE <stdlib.h>   /*Header for the dynamic memory function*/
+#  define LV_MEM_CUSTOM_ALLOC   malloc       /*Wrapper to malloc*/
+#  define LV_MEM_CUSTOM_FREE    free         /*Wrapper to free*/
+#endif     /*LV_MEM_CUSTOM*/
+
+/* Garbage Collector settings
+ * Used if lvgl is binded to higher level language and the memory is managed by that language */
+#define LV_ENABLE_GC 0
+#if LV_ENABLE_GC != 0
+#  define LV_GC_INCLUDE "gc.h"                           /*Include Garbage Collector related things*/
+#  define LV_MEM_CUSTOM_REALLOC   your_realloc           /*Wrapper to realloc*/
+#  define LV_MEM_CUSTOM_GET_SIZE  your_mem_get_size      /*Wrapper to lv_mem_get_size*/
+#endif /* LV_ENABLE_GC */
+
+/*=======================
+   Input device settings
+ *=======================*/
+
+/* Input device default settings.
+ * Can be changed in the Input device driver (`lv_indev_drv_t`)*/
+
+/* Input device read period in milliseconds */
+#define LV_INDEV_DEF_READ_PERIOD          30
+
+/* Drag threshold in pixels */
+#define LV_INDEV_DEF_DRAG_LIMIT           10
+
+/* Drag throw slow-down in [%]. Greater value -> faster slow-down */
+#define LV_INDEV_DEF_DRAG_THROW           10
+
+/* Long press time in milliseconds.
+ * Time to send `LV_EVENT_LONG_PRESSSED`) */
+#define LV_INDEV_DEF_LONG_PRESS_TIME      400
+
+/* Repeated trigger period in long press [ms]
+ * Time between `LV_EVENT_LONG_PRESSED_REPEAT */
+#define LV_INDEV_DEF_LONG_PRESS_REP_TIME  100
+
+
+/* Gesture threshold in pixels */
+#define LV_INDEV_DEF_GESTURE_LIMIT        50
+
+/* Gesture min velocity at release before swipe (pixels)*/
+#define LV_INDEV_DEF_GESTURE_MIN_VELOCITY 3
+
+/*==================
+ * Feature usage
+ *==================*/
+
+/*1: Enable the Animations */
+#define LV_USE_ANIMATION        1
+#if LV_USE_ANIMATION
+
+/*Declare the type of the user data of animations (can be e.g. `void *`, `int`, `struct`)*/
+typedef void * lv_anim_user_data_t;
+
+#endif
+
+/* 1: Enable shadow drawing*/
+#define LV_USE_SHADOW           1
+#if LV_USE_SHADOW
+/* Allow buffering some shadow calculation
+ * LV_SHADOW_CACHE_SIZE is the max. shadow size to buffer,
+ * where shadow size is `shadow_width + radius`
+ * Caching has LV_SHADOW_CACHE_SIZE^2 RAM cost*/
+#define LV_SHADOW_CACHE_SIZE    0
+#endif
+
+/* 1: Use other blend modes than normal (`LV_BLEND_MODE_...`)*/
+#define LV_USE_BLEND_MODES      1
+
+/* 1: Use the `opa_scale` style property to set the opacity of an object and its children at once*/
+#define LV_USE_OPA_SCALE        1
+
+/* 1: Use image zoom and rotation*/
+#define LV_USE_IMG_TRANSFORM    1
+
+/* 1: Enable object groups (for keyboard/encoder navigation) */
+#define LV_USE_GROUP            1
+#if LV_USE_GROUP
+typedef void * lv_group_user_data_t;
+#endif  /*LV_USE_GROUP*/
+
+/* 1: Enable GPU interface*/
+#define LV_USE_GPU              1   /*Only enables `gpu_fill_cb` and `gpu_blend_cb` in the disp. drv- */
+#define LV_USE_GPU_STM32_DMA2D  0
+
+/* 1: Enable file system (might be required for images */
+#define LV_USE_FILESYSTEM       1
+#if LV_USE_FILESYSTEM
+/*Declare the type of the user data of file system drivers (can be e.g. `void *`, `int`, `struct`)*/
+typedef void * lv_fs_drv_user_data_t;
+#endif
+
+/*1: Add a `user_data` to drivers and objects*/
+#define LV_USE_USER_DATA        1
+
+/*1: Show CPU usage and FPS count in the right bottom corner*/
+#define LV_USE_PERF_MONITOR     0
+
+/*1: Use the functions and types from the older API if possible */
+#define LV_USE_API_EXTENSION_V6  1
+
+/*========================
+ * Image decoder and cache
+ *========================*/
+
+/* 1: Enable indexed (palette) images */
+#define LV_IMG_CF_INDEXED       1
+
+/* 1: Enable alpha indexed images */
+#define LV_IMG_CF_ALPHA         1
+
+/* Default image cache size. Image caching keeps the images opened.
+ * If only the built-in image formats are used there is no real advantage of caching.
+ * (I.e. no new image decoder is added)
+ * With complex image decoders (e.g. PNG or JPG) caching can save the continuous open/decode of images.
+ * However the opened images might consume additional RAM.
+ * LV_IMG_CACHE_DEF_SIZE must be >= 1 */
+#define LV_IMG_CACHE_DEF_SIZE       1
+
+/*Declare the type of the user data of image decoder (can be e.g. `void *`, `int`, `struct`)*/
+typedef void * lv_img_decoder_user_data_t;
+
+/*=====================
+ *  Compiler settings
+ *====================*/
+/* Define a custom attribute to `lv_tick_inc` function */
+#define LV_ATTRIBUTE_TICK_INC
+
+/* Define a custom attribute to `lv_task_handler` function */
+#define LV_ATTRIBUTE_TASK_HANDLER
+
+/* Define a custom attribute to `lv_disp_flush_ready` function */
+#define LV_ATTRIBUTE_FLUSH_READY
+
+/* With size optimization (-Os) the compiler might not align data to
+ * 4 or 8 byte boundary. This alignment will be explicitly applied where needed.
+ * E.g. __attribute__((aligned(4))) */
+#define LV_ATTRIBUTE_MEM_ALIGN
+
+/* Attribute to mark large constant arrays for example
+ * font's bitmaps */
+#define LV_ATTRIBUTE_LARGE_CONST
+
+/* Prefix performance critical functions to place them into a faster memory (e.g RAM)
+ * Uses 15-20 kB extra memory */
+#define LV_ATTRIBUTE_FAST_MEM
+
+/* Export integer constant to binding.
+ * This macro is used with constants in the form of LV_<CONST> that
+ * should also appear on lvgl binding API such as Micropython
+ *
+ * The default value just prevents a GCC warning.
+ */
+#define LV_EXPORT_CONST_INT(int_value) struct _silence_gcc_warning
+
+/*===================
+ *  HAL settings
+ *==================*/
+
+/* 1: use a custom tick source.
+ * It removes the need to manually update the tick with `lv_tick_inc`) */
+#define LV_TICK_CUSTOM     0
+#if LV_TICK_CUSTOM == 1
+#define LV_TICK_CUSTOM_INCLUDE  "something.h"       /*Header for the sys time function*/
+#define LV_TICK_CUSTOM_SYS_TIME_EXPR (millis())     /*Expression evaluating to current systime in ms*/
+#endif   /*LV_TICK_CUSTOM*/
+
+typedef void * lv_disp_drv_user_data_t;             /*Type of user data in the display driver*/
+typedef void * lv_indev_drv_user_data_t;            /*Type of user data in the input device driver*/
+
+/*================
+ * Log settings
+ *===============*/
+
+/*1: Enable the log module*/
+#define LV_USE_LOG      0
+#if LV_USE_LOG
+/* How important log should be added:
+ * LV_LOG_LEVEL_TRACE       A lot of logs to give detailed information
+ * LV_LOG_LEVEL_INFO        Log important events
+ * LV_LOG_LEVEL_WARN        Log if something unwanted happened but didn't cause a problem
+ * LV_LOG_LEVEL_ERROR       Only critical issue, when the system may fail
+ * LV_LOG_LEVEL_NONE        Do not log anything
+ */
+#  define LV_LOG_LEVEL    LV_LOG_LEVEL_WARN
+
+/* 1: Print the log with 'printf';
+ * 0: user need to register a callback with `lv_log_register_print_cb`*/
+#  define LV_LOG_PRINTF   0
+#endif  /*LV_USE_LOG*/
+
+/*=================
+ * Debug settings
+ *================*/
+
+/* If Debug is enabled LittelvGL validates the parameters of the functions.
+ * If an invalid parameter is found an error log message is printed and
+ * the MCU halts at the error. (`LV_USE_LOG` should be enabled)
+ * If you are debugging the MCU you can pause
+ * the debugger to see exactly where  the issue is.
+ *
+ * The behavior of asserts can be overwritten by redefining them here.
+ * E.g. #define LV_ASSERT_MEM(p)  <my_assert_code>
+ */
+#define LV_USE_DEBUG        1
+#if LV_USE_DEBUG
+
+/*Check if the parameter is NULL. (Quite fast) */
+#define LV_USE_ASSERT_NULL      1
+
+/*Checks is the memory is successfully allocated or no. (Quite fast)*/
+#define LV_USE_ASSERT_MEM       1
+
+/*Check the integrity of `lv_mem` after critical operations. (Slow)*/
+#define LV_USE_ASSERT_MEM_INTEGRITY       0
+
+/* Check the strings.
+ * Search for NULL, very long strings, invalid characters, and unnatural repetitions. (Slow)
+ * If disabled `LV_USE_ASSERT_NULL` will be performed instead (if it's enabled) */
+#define LV_USE_ASSERT_STR       0
+
+/* Check NULL, the object's type and existence (e.g. not deleted). (Quite slow)
+ * If disabled `LV_USE_ASSERT_NULL` will be performed instead (if it's enabled) */
+#define LV_USE_ASSERT_OBJ       0
+
+/*Check if the styles are properly initialized. (Fast)*/
+#define LV_USE_ASSERT_STYLE     0
+
+#endif /*LV_USE_DEBUG*/
+
+/*==================
+ *    FONT USAGE
+ *===================*/
+
+/* The built-in fonts contains the ASCII range and some Symbols with  4 bit-per-pixel.
+ * The symbols are available via `LV_SYMBOL_...` defines
+ * More info about fonts: https://docs.lvgl.com/#Fonts
+ * To create a new font go to: https://lvgl.com/ttf-font-to-c-array
+ */
+
+/* Montserrat fonts with bpp = 4
+ * https://fonts.google.com/specimen/Montserrat  */
+#define LV_FONT_MONTSERRAT_12    0
+#define LV_FONT_MONTSERRAT_14    0
+#define LV_FONT_MONTSERRAT_16    1
+#define LV_FONT_MONTSERRAT_18    0
+#define LV_FONT_MONTSERRAT_20    0
+#define LV_FONT_MONTSERRAT_22    0
+#define LV_FONT_MONTSERRAT_24    0
+#define LV_FONT_MONTSERRAT_26    0
+#define LV_FONT_MONTSERRAT_28    0
+#define LV_FONT_MONTSERRAT_30    0
+#define LV_FONT_MONTSERRAT_32    0
+#define LV_FONT_MONTSERRAT_34    0
+#define LV_FONT_MONTSERRAT_36    0
+#define LV_FONT_MONTSERRAT_38    0
+#define LV_FONT_MONTSERRAT_40    0
+#define LV_FONT_MONTSERRAT_42    0
+#define LV_FONT_MONTSERRAT_44    0
+#define LV_FONT_MONTSERRAT_46    0
+#define LV_FONT_MONTSERRAT_48    0
+
+/* Demonstrate special features */
+#define LV_FONT_MONTSERRAT_12_SUBPX      0
+#define LV_FONT_MONTSERRAT_28_COMPRESSED 0  /*bpp = 3*/
+#define LV_FONT_DEJAVU_16_PERSIAN_HEBREW 0  /*Hebrew, Arabic, PErisan letters and all their forms*/
+#define LV_FONT_SIMSUN_16_CJK            0  /*1000 most common CJK radicals*/
+
+/*Pixel perfect monospace font
+ * http://pelulamu.net/unscii/ */
+#define LV_FONT_UNSCII_8     0
+
+/* Optionally declare your custom fonts here.
+ * You can use these fonts as default font too
+ * and they will be available globally. E.g.
+ * #define LV_FONT_CUSTOM_DECLARE LV_FONT_DECLARE(my_font_1) \
+ *                                LV_FONT_DECLARE(my_font_2)
+ */
+#define LV_FONT_CUSTOM_DECLARE
+
+/* Enable it if you have fonts with a lot of characters.
+ * The limit depends on the font size, font face and bpp
+ * but with > 10,000 characters if you see issues probably you need to enable it.*/
+#define LV_FONT_FMT_TXT_LARGE   0
+
+/* Set the pixel order of the display.
+ * Important only if "subpx fonts" are used.
+ * With "normal" font it doesn't matter.
+ */
+#define LV_FONT_SUBPX_BGR    0
+
+/*Declare the type of the user data of fonts (can be e.g. `void *`, `int`, `struct`)*/
+typedef void * lv_font_user_data_t;
+
+/*================
+ *  THEME USAGE
+ *================*/
+
+/*Always enable at least on theme*/
+
+/* No theme, you can apply your styles as you need
+ * No flags. Set LV_THEME_DEFAULT_FLAG 0 */
+ #define LV_USE_THEME_EMPTY       1
+
+/*Simple to the create your theme based on it
+ * No flags. Set LV_THEME_DEFAULT_FLAG 0 */
+ #define LV_USE_THEME_TEMPLATE    1
+
+/* A fast and impressive theme.
+ * Flags:
+ * LV_THEME_MATERIAL_FLAG_LIGHT: light theme
+ * LV_THEME_MATERIAL_FLAG_DARK: dark theme*/
+ #define LV_USE_THEME_MATERIAL    1
+
+/* Mono-color theme for monochrome displays.
+ * If LV_THEME_DEFAULT_COLOR_PRIMARY is LV_COLOR_BLACK the
+ * texts and borders will be black and the background will be
+ * white. Else the colors are inverted.
+ * No flags. Set LV_THEME_DEFAULT_FLAG 0 */
+ #define LV_USE_THEME_MONO        1
+
+#define LV_THEME_DEFAULT_INCLUDE            <stdint.h>      /*Include a header for the init. function*/
+#define LV_THEME_DEFAULT_INIT               lv_theme_material_init
+#define LV_THEME_DEFAULT_COLOR_PRIMARY      LV_COLOR_RED
+#define LV_THEME_DEFAULT_COLOR_SECONDARY    LV_COLOR_BLUE
+#define LV_THEME_DEFAULT_FLAG               LV_THEME_MATERIAL_FLAG_LIGHT
+#define LV_THEME_DEFAULT_FONT_SMALL         &lv_font_montserrat_16
+#define LV_THEME_DEFAULT_FONT_NORMAL        &lv_font_montserrat_16
+#define LV_THEME_DEFAULT_FONT_SUBTITLE      &lv_font_montserrat_16
+#define LV_THEME_DEFAULT_FONT_TITLE         &lv_font_montserrat_16
+
+/*=================
+ *  Text settings
+ *=================*/
+
+/* Select a character encoding for strings.
+ * Your IDE or editor should have the same character encoding
+ * - LV_TXT_ENC_UTF8
+ * - LV_TXT_ENC_ASCII
+ * */
+#define LV_TXT_ENC LV_TXT_ENC_UTF8
+
+ /*Can break (wrap) texts on these chars*/
+#define LV_TXT_BREAK_CHARS                  " ,.;:-_"
+
+/* If a word is at least this long, will break wherever "prettiest"
+ * To disable, set to a value <= 0 */
+#define LV_TXT_LINE_BREAK_LONG_LEN          0
+
+/* Minimum number of characters in a long word to put on a line before a break.
+ * Depends on LV_TXT_LINE_BREAK_LONG_LEN. */
+#define LV_TXT_LINE_BREAK_LONG_PRE_MIN_LEN  3
+
+/* Minimum number of characters in a long word to put on a line after a break.
+ * Depends on LV_TXT_LINE_BREAK_LONG_LEN. */
+#define LV_TXT_LINE_BREAK_LONG_POST_MIN_LEN 3
+
+/* The control character to use for signalling text recoloring. */
+#define LV_TXT_COLOR_CMD "#"
+
+/* Support bidirectional texts.
+ * Allows mixing Left-to-Right and Right-to-Left texts.
+ * The direction will be processed according to the Unicode Bidirectioanl Algorithm:
+ * https://www.w3.org/International/articles/inline-bidi-markup/uba-basics*/
+#define LV_USE_BIDI     0
+#if LV_USE_BIDI
+/* Set the default direction. Supported values:
+ * `LV_BIDI_DIR_LTR` Left-to-Right
+ * `LV_BIDI_DIR_RTL` Right-to-Left
+ * `LV_BIDI_DIR_AUTO` detect texts base direction */
+#define LV_BIDI_BASE_DIR_DEF  LV_BIDI_DIR_AUTO
+#endif
+
+/* Enable Arabic/Persian processing
+ * In these languages characters should be replaced with
+ * an other form based on their position in the text */
+#define LV_USE_ARABIC_PERSIAN_CHARS 0
+
+/*Change the built in (v)snprintf functions*/
+#define LV_SPRINTF_CUSTOM   0
+#if LV_SPRINTF_CUSTOM
+#  define LV_SPRINTF_INCLUDE <stdio.h>
+#  define lv_snprintf     snprintf
+#  define lv_vsnprintf    vsnprintf
+#else   /*!LV_SPRINTF_CUSTOM*/
+#  define LV_SPRINTF_DISABLE_FLOAT 1
+#endif  /*LV_SPRINTF_CUSTOM*/
+
+/*===================
+ *  LV_OBJ SETTINGS
+ *==================*/
+
+#if LV_USE_USER_DATA
+/*Declare the type of the user data of object (can be e.g. `void *`, `int`, `struct`)*/
+typedef void * lv_obj_user_data_t;
+/*Provide a function to free user data*/
+#define LV_USE_USER_DATA_FREE 0
+#if LV_USE_USER_DATA_FREE
+#  define LV_USER_DATA_FREE_INCLUDE  "something.h"  /*Header for user data free function*/
+/* Function prototype : void user_data_free(lv_obj_t * obj); */
+#  define LV_USER_DATA_FREE  (user_data_free)       /*Invoking for user data free function*/
+#endif
+#endif
+
+/*1: enable `lv_obj_realaign()` based on `lv_obj_align()` parameters*/
+#define LV_USE_OBJ_REALIGN          1
+
+/* Enable to make the object clickable on a larger area.
+ * LV_EXT_CLICK_AREA_OFF or 0: Disable this feature
+ * LV_EXT_CLICK_AREA_TINY: The extra area can be adjusted horizontally and vertically (0..255 px)
+ * LV_EXT_CLICK_AREA_FULL: The extra area can be adjusted in all 4 directions (-32k..+32k px)
+ */
+#define LV_USE_EXT_CLICK_AREA  LV_EXT_CLICK_AREA_TINY
+
+/*==================
+ *  LV OBJ X USAGE
+ *================*/
+/*
+ * Documentation of the object types: https://docs.lvgl.com/#Object-types
+ */
+
+/*Arc (dependencies: -)*/
+#define LV_USE_ARC      1
+
+/*Bar (dependencies: -)*/
+#define LV_USE_BAR      1
+
+/*Button (dependencies: lv_cont*/
+#define LV_USE_BTN      1
+
+/*Button matrix (dependencies: -)*/
+#define LV_USE_BTNMATRIX     1
+
+/*Calendar (dependencies: -)*/
+#define LV_USE_CALENDAR 1
+
+/*Canvas (dependencies: lv_img)*/
+#define LV_USE_CANVAS   1
+
+/*Check box (dependencies: lv_btn, lv_label)*/
+#define LV_USE_CHECKBOX       1
+
+/*Chart (dependencies: -)*/
+#define LV_USE_CHART    1
+#if LV_USE_CHART
+#  define LV_CHART_AXIS_TICK_LABEL_MAX_LEN    256
+#endif
+
+/*Container (dependencies: -*/
+#define LV_USE_CONT     1
+
+/*Color picker (dependencies: -*/
+#define LV_USE_CPICKER   1
+
+/*Drop down list (dependencies: lv_page, lv_label, lv_symbol_def.h)*/
+#define LV_USE_DROPDOWN    1
+#if LV_USE_DROPDOWN != 0
+/*Open and close default animation time [ms] (0: no animation)*/
+#  define LV_DROPDOWN_DEF_ANIM_TIME     200
+#endif
+
+/*Gauge (dependencies:lv_bar, lv_linemeter)*/
+#define LV_USE_GAUGE    1
+
+/*Image (dependencies: lv_label*/
+#define LV_USE_IMG      1
+
+/*Image Button (dependencies: lv_btn*/
+#define LV_USE_IMGBTN   1
+#if LV_USE_IMGBTN
+/*1: The imgbtn requires left, mid and right parts and the width can be set freely*/
+#  define LV_IMGBTN_TILED 0
+#endif
+
+/*Keyboard (dependencies: lv_btnm)*/
+#define LV_USE_KEYBOARD       1
+
+/*Label (dependencies: -*/
+#define LV_USE_LABEL    1
+#if LV_USE_LABEL != 0
+/*Hor, or ver. scroll speed [px/sec] in 'LV_LABEL_LONG_ROLL/ROLL_CIRC' mode*/
+#  define LV_LABEL_DEF_SCROLL_SPEED       25
+
+/* Waiting period at beginning/end of animation cycle */
+#  define LV_LABEL_WAIT_CHAR_COUNT        3
+
+/*Enable selecting text of the label */
+#  define LV_LABEL_TEXT_SEL               0
+
+/*Store extra some info in labels (12 bytes) to speed up drawing of very long texts*/
+#  define LV_LABEL_LONG_TXT_HINT          0
+#endif
+
+/*LED (dependencies: -)*/
+#define LV_USE_LED      1
+#if LV_USE_LED
+#  define LV_LED_BRIGHT_MIN  120      /*Minimal brightness*/
+#  define LV_LED_BRIGHT_MAX  255     /*Maximal brightness*/
+#endif
+
+/*Line (dependencies: -*/
+#define LV_USE_LINE     1
+
+/*List (dependencies: lv_page, lv_btn, lv_label, (lv_img optionally for icons ))*/
+#define LV_USE_LIST     1
+#if LV_USE_LIST != 0
+/*Default animation time of focusing to a list element [ms] (0: no animation)  */
+#  define LV_LIST_DEF_ANIM_TIME  100
+#endif
+
+/*Line meter (dependencies: *;)*/
+#define LV_USE_LINEMETER   1
+#if LV_USE_LINEMETER
+/* Draw line more precisely at cost of performance.
+ * Useful if there are lot of lines any minor are visible
+ * 0: No extra precision
+ * 1: Some extra precision
+ * 2: Best precision
+ */
+#  define LV_LINEMETER_PRECISE    0
+#endif
+
+/*Mask (dependencies: -)*/
+#define LV_USE_OBJMASK  1
+
+/*Message box (dependencies: lv_rect, lv_btnm, lv_label)*/
+#define LV_USE_MSGBOX     1
+
+/*Page (dependencies: lv_cont)*/
+#define LV_USE_PAGE     1
+#if LV_USE_PAGE != 0
+/*Focus default animation time [ms] (0: no animation)*/
+#  define LV_PAGE_DEF_ANIM_TIME     400
+#endif
+
+/*Preload (dependencies: lv_arc, lv_anim)*/
+#define LV_USE_SPINNER      1
+#if LV_USE_SPINNER != 0
+#  define LV_SPINNER_DEF_ARC_LENGTH   60      /*[deg]*/
+#  define LV_SPINNER_DEF_SPIN_TIME    1000    /*[ms]*/
+#  define LV_SPINNER_DEF_ANIM         LV_SPINNER_TYPE_SPINNING_ARC
+#endif
+
+/*Roller (dependencies: lv_ddlist)*/
+#define LV_USE_ROLLER    1
+#if LV_USE_ROLLER != 0
+/*Focus animation time [ms] (0: no animation)*/
+#  define LV_ROLLER_DEF_ANIM_TIME     200
+
+/*Number of extra "pages" when the roller is infinite*/
+#  define LV_ROLLER_INF_PAGES         7
+#endif
+
+/*Slider (dependencies: lv_bar)*/
+#define LV_USE_SLIDER    1
+
+/*Spinbox (dependencies: lv_ta)*/
+#define LV_USE_SPINBOX       1
+
+/*Switch (dependencies: lv_slider)*/
+#define LV_USE_SWITCH       1
+
+/*Text area (dependencies: lv_label, lv_page)*/
+#define LV_USE_TEXTAREA       1
+#if LV_USE_TEXTAREA != 0
+#  define LV_TEXTAREA_DEF_CURSOR_BLINK_TIME 400     /*ms*/
+#  define LV_TEXTAREA_DEF_PWD_SHOW_TIME     1500    /*ms*/
+#endif
+
+/*Table (dependencies: lv_label)*/
+#define LV_USE_TABLE    1
+#if LV_USE_TABLE
+#  define LV_TABLE_COL_MAX    12
+#endif
+
+/*Tab (dependencies: lv_page, lv_btnm)*/
+#define LV_USE_TABVIEW      1
+#  if LV_USE_TABVIEW != 0
+/*Time of slide animation [ms] (0: no animation)*/
+#  define LV_TABVIEW_DEF_ANIM_TIME    300
+#endif
+
+/*Tileview (dependencies: lv_page) */
+#define LV_USE_TILEVIEW     1
+#if LV_USE_TILEVIEW
+/*Time of slide animation [ms] (0: no animation)*/
+#  define LV_TILEVIEW_DEF_ANIM_TIME   300
+#endif
+
+/*Window (dependencies: lv_cont, lv_btn, lv_label, lv_img, lv_page)*/
+#define LV_USE_WIN      1
+
+/*==================
+ * Non-user section
+ *==================*/
+
+#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)    /* Disable warnings for Visual Studio*/
+#  define _CRT_SECURE_NO_WARNINGS
+#endif
+
+/*--END OF LV_CONF_H--*/
+
+#endif /*LV_CONF_H*/
+
+#endif /*End of "Content enable"*/

lvgl-codegen/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "lvgl-codegen"
+version = "0.5.2"
+description = "Code generation based on LVGL source code"
+authors = ["Rafael Caricio <crates.lvgl@caric.io>"]
+readme = "README.md"
+edition = "2018"
+license = "MIT"
+repository = "https://github.com/rafaelcaricio/lvgl-rs"
+
+[dependencies]
+regex = "1.4.3"
+quote = "1.0.9"
+lazy_static = "1.4.0"
+proc-macro2 = "1.0.27"
+Inflector = "0.11.4"
+syn = { version = "1.0.72", features = ["full"]}
+

lvgl-codegen/README.md

@@ -0,0 +1,2 @@
+# LVGL Code Generation
+This is the code generation crate for safe bindings to [`lvgl-rs`](https://github.com/rafaelcaricio/lvgl-rs). This crate is only supposed to be used to build `lvgl-rs`.

lvgl-codegen/src/lib.rs

@@ -0,0 +1,654 @@
+use inflector::cases::pascalcase::to_pascal_case;
+use lazy_static::lazy_static;
+use proc_macro2::{Ident, TokenStream};
+use quote::quote;
+use quote::{format_ident, ToTokens};
+use regex::Regex;
+use std::collections::HashMap;
+use std::error::Error;
+use syn::{FnArg, ForeignItem, ForeignItemFn, Item, ReturnType};
+
+type CGResult<T> = Result<T, Box<dyn Error>>;
+
+const LIB_PREFIX: &str = "lv_";
+
+lazy_static! {
+    static ref TYPE_MAPPINGS: HashMap<&'static str, &'static str> = [
+        ("u16", "u16"),
+        ("i32", "i32"),
+        ("u8", "u8"),
+        ("bool", "bool"),
+        ("* const cty :: c_char", "_"),
+    ]
+    .iter()
+    .cloned()
+    .collect();
+}
+
+#[derive(Debug, Copy, Clone)]
+pub enum WrapperError {
+    Skip,
+}
+
+pub type WrapperResult<T> = Result<T, WrapperError>;
+
+pub trait Rusty {
+    type Parent;
+
+    fn code(&self, parent: &Self::Parent) -> WrapperResult<TokenStream>;
+}
+
+#[derive(Clone)]
+pub struct LvWidget {
+    name: String,
+    methods: Vec<LvFunc>,
+}
+
+impl Rusty for LvWidget {
+    type Parent = ();
+
+    fn code(&self, _parent: &Self::Parent) -> WrapperResult<TokenStream> {
+        // We don't generate for the generic Obj
+        if self.name.as_str().eq("obj") {
+            return Err(WrapperError::Skip);
+        }
+
+        let widget_name = format_ident!("{}", to_pascal_case(self.name.as_str()));
+        let methods: Vec<TokenStream> = self.methods.iter().flat_map(|m| m.code(self)).collect();
+        Ok(quote! {
+            define_object!(#widget_name);
+
+            impl #widget_name {
+                #(#methods)*
+            }
+        })
+    }
+}
+
+#[derive(Clone)]
+pub struct LvFunc {
+    name: String,
+    args: Vec<LvArg>,
+    ret: Option<LvType>,
+}
+
+impl LvFunc {
+    pub fn new(name: String, args: Vec<LvArg>, ret: Option<LvType>) -> Self {
+        Self { name, args, ret }
+    }
+
+    pub fn is_method(&self) -> bool {
+        if !self.args.is_empty() {
+            let first_arg = &self.args[0];
+            return first_arg.typ.literal_name.contains("lv_obj_t");
+        }
+        false
+    }
+}
+
+impl Rusty for LvFunc {
+    type Parent = LvWidget;
+
+    fn code(&self, parent: &Self::Parent) -> WrapperResult<TokenStream> {
+        let templ = format!("{}{}_", LIB_PREFIX, parent.name.as_str());
+        let new_name = self.name.replace(templ.as_str(), "");
+        let func_name = format_ident!("{}", new_name);
+        let original_func_name = format_ident!("{}", self.name.as_str());
+
+        // generate constructor
+        if new_name.as_str().eq("create") {
+            return Ok(quote! {
+
+                pub fn new<C>(parent: &mut C) -> crate::LvResult<Self>
+                where
+                    C: crate::NativeObject,
+                {
+                    unsafe {
+                        let ptr = lvgl_sys::#original_func_name(parent.raw()?.as_mut(), core::ptr::null_mut());
+                        if let Some(raw) = core::ptr::NonNull::new(ptr) {
+                            let core = <crate::Obj as crate::Widget>::from_raw(raw);
+                            Ok(Self { core })
+                        } else {
+                            Err(crate::LvError::InvalidReference)
+                        }
+                    }
+                }
+
+            });
+        }
+
+        // We don't deal with methods that return types yet
+        if self.ret.is_some() {
+            return Err(WrapperError::Skip);
+        }
+
+        // Make sure all arguments can be generated, skip the first arg (self)!
+        for arg in self.args.iter().skip(1) {
+            arg.code(self)?;
+        }
+
+        let args_decl = self
+            .args
+            .iter()
+            .enumerate()
+            .fold(quote!(), |args, (i, arg)| {
+                // if first arg is `const`, then it should be immutable
+                let next_arg = if i == 0 {
+                    if arg.get_type().is_const() {
+                        quote!(&self)
+                    } else {
+                        quote!(&mut self)
+                    }
+                } else {
+                    arg.code(self).unwrap()
+                };
+                if args.is_empty() {
+                    quote! {
+                        #next_arg
+                    }
+                } else {
+                    quote! {
+                        #args, #next_arg
+                    }
+                }
+            });
+
+        let args_processing = self
+            .args
+            .iter()
+            .enumerate()
+            .fold(quote!(), |args, (i, arg)| {
+                // if first arg is `const`, then it should be immutable
+                let next_arg = if i == 0 {
+                    quote!()
+                } else {
+                    let var = arg.get_processing();
+                    quote!(#var)
+                };
+                if args.is_empty() {
+                    quote! {
+                        #next_arg
+                    }
+                } else {
+                    quote! {
+                        #args
+                        #next_arg
+                    }
+                }
+            });
+
+        let args_call = self
+            .args
+            .iter()
+            .enumerate()
+            .fold(quote!(), |args, (i, arg)| {
+                // if first arg is `const`, then it should be immutable
+                let next_arg = if i == 0 {
+                    quote!(self.core.raw()?.as_mut())
+                } else {
+                    let var = arg.get_value_usage();
+                    quote!(#var)
+                };
+                if args.is_empty() {
+                    quote! {
+                        #next_arg
+                    }
+                } else {
+                    quote! {
+                        #args, #next_arg
+                    }
+                }
+            });
+
+        // TODO: Handle methods that return types
+        Ok(quote! {
+            pub fn #func_name(#args_decl) -> crate::LvResult<()> {
+                #args_processing
+                unsafe {
+                    lvgl_sys::#original_func_name(#args_call);
+                }
+                Ok(())
+            }
+        })
+    }
+}
+
+impl From<ForeignItemFn> for LvFunc {
+    fn from(ffi: ForeignItemFn) -> Self {
+        let ret = match ffi.sig.output {
+            ReturnType::Default => None,
+            ReturnType::Type(_, typ) => Some(typ.into()),
+        };
+        Self::new(
+            ffi.sig.ident.to_string(),
+            ffi.sig
+                .inputs
+                .iter()
+                .filter_map(|fa| {
+                    // Since we know those are foreign functions, we only care about typed arguments
+                    if let FnArg::Typed(tya) = fa {
+                        Some(tya)
+                    } else {
+                        None
+                    }
+                })
+                .map(|a| a.clone().into())
+                .collect::<Vec<LvArg>>(),
+            ret,
+        )
+    }
+}
+
+#[derive(Clone)]
+pub struct LvArg {
+    name: String,
+    typ: LvType,
+}
+
+impl From<syn::PatType> for LvArg {
+    fn from(fa: syn::PatType) -> Self {
+        Self::new(fa.pat.to_token_stream().to_string(), fa.ty.into())
+    }
+}
+
+impl LvArg {
+    pub fn new(name: String, typ: LvType) -> Self {
+        Self { name, typ }
+    }
+
+    pub fn get_name_ident(&self) -> Ident {
+        // Filter Rust language keywords
+        syn::parse_str::<syn::Ident>(self.name.as_str())
+            .unwrap_or_else(|_| format_ident!("r#{}", self.name.as_str()))
+    }
+
+    pub fn get_processing(&self) -> TokenStream {
+        // TODO: A better way to handle this, instead of `is_sometype()`, is using the Rust
+        //       type system itself.
+
+        // No need to pre-process this type of argument
+        quote! {}
+    }
+
+    pub fn get_value_usage(&self) -> TokenStream {
+        let ident = self.get_name_ident();
+        if self.typ.is_str() {
+            quote! {
+                #ident.as_ptr()
+            }
+        } else {
+            quote! {
+                #ident
+            }
+        }
+    }
+
+    pub fn get_type(&self) -> &LvType {
+        &self.typ
+    }
+}
+
+impl Rusty for LvArg {
+    type Parent = LvFunc;
+
+    fn code(&self, _parent: &Self::Parent) -> WrapperResult<TokenStream> {
+        let name = self.get_name_ident();
+        let typ = self.typ.code(self)?;
+        Ok(quote! {
+            #name: #typ
+        })
+    }
+}
+
+#[derive(Clone)]
+pub struct LvType {
+    literal_name: String,
+    _r_type: Option<Box<syn::Type>>,
+}
+
+impl LvType {
+    pub fn new(literal_name: String) -> Self {
+        Self {
+            literal_name,
+            _r_type: None,
+        }
+    }
+
+    pub fn from(r_type: Box<syn::Type>) -> Self {
+        Self {
+            literal_name: r_type.to_token_stream().to_string(),
+            _r_type: Some(r_type),
+        }
+    }
+
+    pub fn is_const(&self) -> bool {
+        self.literal_name.starts_with("const ")
+    }
+
+    pub fn is_str(&self) -> bool {
+        self.literal_name.ends_with("* const cty :: c_char")
+    }
+}
+
+impl Rusty for LvType {
+    type Parent = LvArg;
+
+    fn code(&self, _parent: &Self::Parent) -> WrapperResult<TokenStream> {
+        match TYPE_MAPPINGS.get(self.literal_name.as_str()) {
+            Some(name) => {
+                let val = if self.is_str() {
+                    quote!(&cstr_core::CStr)
+                } else {
+                    let ident = format_ident!("{}", name);
+                    quote!(#ident)
+                };
+                Ok(quote! {
+                    #val
+                })
+            }
+            None => Err(WrapperError::Skip),
+        }
+    }
+}
+
+impl From<Box<syn::Type>> for LvType {
+    fn from(t: Box<syn::Type>) -> Self {
+        Self::from(t)
+    }
+}
+
+pub struct CodeGen {
+    functions: Vec<LvFunc>,
+    widgets: Vec<LvWidget>,
+}
+
+impl CodeGen {
+    pub fn from(code: &str) -> CGResult<Self> {
+        let functions = Self::load_func_defs(code)?;
+        let widgets = Self::extract_widgets(&functions)?;
+        Ok(Self { functions, widgets })
+    }
+
+    pub fn get_widgets(&self) -> &Vec<LvWidget> {
+        &self.widgets
+    }
+
+    fn extract_widgets(functions: &[LvFunc]) -> CGResult<Vec<LvWidget>> {
+        let widget_names = Self::get_widget_names(functions);
+
+        let widgets = functions.iter().fold(HashMap::new(), |mut ws, f| {
+            for widget_name in &widget_names {
+                if f.name
+                    .starts_with(format!("{}{}", LIB_PREFIX, widget_name).as_str())
+                    && f.is_method()
+                {
+                    ws.entry(widget_name.clone())
+                        .or_insert_with(|| LvWidget {
+                            name: widget_name.clone(),
+                            methods: Vec::new(),
+                        })
+                        .methods
+                        .push(f.clone())
+                }
+            }
+            ws
+        });
+
+        Ok(widgets.values().cloned().collect())
+    }
+
+    fn get_widget_names(functions: &[LvFunc]) -> Vec<String> {
+        let reg = format!("^{}([^_]+)_create$", LIB_PREFIX);
+        let create_func = Regex::new(reg.as_str()).unwrap();
+
+        functions
+            .iter()
+            .filter(|e| create_func.is_match(e.name.as_str()) && e.args.len() == 2)
+            .map(|f| {
+                String::from(
+                    create_func
+                        .captures(f.name.as_str())
+                        .unwrap()
+                        .get(1)
+                        .unwrap()
+                        .as_str(),
+                )
+            })
+            .collect::<Vec<_>>()
+    }
+
+    pub fn load_func_defs(bindgen_code: &str) -> CGResult<Vec<LvFunc>> {
+        let ast: syn::File = syn::parse_str(bindgen_code)?;
+        let fns = ast
+            .items
+            .into_iter()
+            .filter_map(|e| {
+                if let Item::ForeignMod(fm) = e {
+                    Some(fm)
+                } else {
+                    None
+                }
+            })
+            .flat_map(|e| {
+                e.items.into_iter().filter_map(|it| {
+                    if let ForeignItem::Fn(f) = it {
+                        Some(f)
+                    } else {
+                        None
+                    }
+                })
+            })
+            .filter(|ff| ff.sig.ident.to_string().starts_with(LIB_PREFIX))
+            .map(|ff| ff.into())
+            .collect::<Vec<LvFunc>>();
+        Ok(fns)
+    }
+
+    pub fn get_function_names(&self) -> CGResult<Vec<String>> {
+        Ok(self.functions.iter().map(|f| f.name.clone()).collect())
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use crate::{CodeGen, LvArg, LvFunc, LvType, LvWidget, Rusty};
+    use quote::quote;
+
+    #[test]
+    fn can_load_bindgen_fns() {
+        let bindgen_code = quote! {
+            extern "C" {
+                #[doc = " Return with the screen of an object"]
+                #[doc = " @param obj pointer to an object"]
+                #[doc = " @return pointer to a screen"]
+                pub fn lv_obj_get_screen(obj: *const lv_obj_t) -> *mut lv_obj_t;
+            }
+        };
+
+        let cg = CodeGen::load_func_defs(bindgen_code.to_string().as_str()).unwrap();
+
+        let ffn = cg.get(0).unwrap();
+        assert_eq!(ffn.name, "lv_obj_get_screen");
+        assert_eq!(ffn.args[0].name, "obj");
+    }
+
+    #[test]
+    fn can_identify_widgets_from_function_names() {
+        let funcs = vec![
+            LvFunc::new(
+                "lv_obj_create".to_string(),
+                vec![
+                    LvArg::new("parent".to_string(), LvType::new("abc".to_string())),
+                    LvArg::new("copy_from".to_string(), LvType::new("bcf".to_string())),
+                ],
+                None,
+            ),
+            LvFunc::new(
+                "lv_btn_create".to_string(),
+                vec![
+                    LvArg::new("parent".to_string(), LvType::new("abc".to_string())),
+                    LvArg::new("copy_from".to_string(), LvType::new("bcf".to_string())),
+                ],
+                None,
+            ),
+            LvFunc::new(
+                "lv_do_something".to_string(),
+                vec![
+                    LvArg::new("parent".to_string(), LvType::new("abc".to_string())),
+                    LvArg::new("copy_from".to_string(), LvType::new("bcf".to_string())),
+                ],
+                None,
+            ),
+            LvFunc::new(
+                "lv_invalid_create".to_string(),
+                vec![LvArg::new(
+                    "parent".to_string(),
+                    LvType::new("abc".to_string()),
+                )],
+                None,
+            ),
+            LvFunc::new(
+                "lv_cb_create".to_string(),
+                vec![
+                    LvArg::new("parent".to_string(), LvType::new("abc".to_string())),
+                    LvArg::new("copy_from".to_string(), LvType::new("bcf".to_string())),
+                ],
+                None,
+            ),
+        ];
+
+        let widget_names = CodeGen::get_widget_names(&funcs);
+
+        assert_eq!(widget_names.len(), 3);
+    }
+
+    #[test]
+    fn generate_method_wrapper() {
+        // pub fn lv_arc_set_bg_end_angle(arc: *mut lv_obj_t, end: u16);
+        let arc_set_bg_end_angle = LvFunc::new(
+            "lv_arc_set_bg_end_angle".to_string(),
+            vec![
+                LvArg::new("arc".to_string(), LvType::new("*mut lv_obj_t".to_string())),
+                LvArg::new("end".to_string(), LvType::new("u16".to_string())),
+            ],
+            None,
+        );
+        let arc_widget = LvWidget {
+            name: "arc".to_string(),
+            methods: vec![],
+        };
+
+        let code = arc_set_bg_end_angle.code(&arc_widget).unwrap();
+        let expected_code = quote! {
+            pub fn set_bg_end_angle(&mut self, end: u16) -> crate::LvResult<()> {
+                unsafe {
+                    lvgl_sys::lv_arc_set_bg_end_angle(self.core.raw()?.as_mut(), end);
+                }
+                Ok(())
+            }
+        };
+
+        assert_eq!(code.to_string(), expected_code.to_string());
+    }
+
+    #[test]
+    fn generate_method_wrapper_for_str_types_as_argument() {
+        let bindgen_code = quote! {
+            extern "C" {
+                #[doc = " Set a new text for a label. Memory will be allocated to store the text by the label."]
+                #[doc = " @param label pointer to a label object"]
+                #[doc = " @param text '\\0' terminated character string. NULL to refresh with the current text."]
+                pub fn lv_label_set_text(label: *mut lv_obj_t, text: *const cty::c_char);
+            }
+        };
+        let cg = CodeGen::load_func_defs(bindgen_code.to_string().as_str()).unwrap();
+
+        let label_set_text = cg.get(0).unwrap().clone();
+        let parent_widget = LvWidget {
+            name: "label".to_string(),
+            methods: vec![],
+        };
+
+        let code = label_set_text.code(&parent_widget).unwrap();
+        let expected_code = quote! {
+
+            pub fn set_text(&mut self, text: &cstr_core::CStr) -> crate::LvResult<()> {
+                unsafe {
+                    lvgl_sys::lv_label_set_text(
+                        self.core.raw()?.as_mut(),
+                        text.as_ptr()
+                    );
+                }
+                Ok(())
+            }
+
+        };
+
+        assert_eq!(code.to_string(), expected_code.to_string());
+    }
+
+    #[test]
+    fn generate_basic_widget_code() {
+        let arc_widget = LvWidget {
+            name: "arc".to_string(),
+            methods: vec![],
+        };
+
+        let code = arc_widget.code(&()).unwrap();
+        let expected_code = quote! {
+            define_object!(Arc);
+
+            impl Arc {
+
+            }
+        };
+
+        assert_eq!(code.to_string(), expected_code.to_string());
+    }
+
+    #[test]
+    fn generate_widget_with_constructor_code() {
+        // pub fn lv_arc_create(par: *mut lv_obj_t, copy: *const lv_obj_t) -> *mut lv_obj_t;
+        let arc_create = LvFunc::new(
+            "lv_arc_create".to_string(),
+            vec![
+                LvArg::new("par".to_string(), LvType::new("*mut lv_obj_t".to_string())),
+                LvArg::new(
+                    "copy".to_string(),
+                    LvType::new("*const lv_obj_t".to_string()),
+                ),
+            ],
+            Some(LvType::new("*mut lv_obj_t".to_string())),
+        );
+
+        let arc_widget = LvWidget {
+            name: "arc".to_string(),
+            methods: vec![arc_create],
+        };
+
+        let code = arc_widget.code(&()).unwrap();
+        let expected_code = quote! {
+            define_object!(Arc);
+
+            impl Arc {
+                pub fn new<C>(parent: &mut C) -> crate::LvResult<Self>
+                where
+                    C: crate::NativeObject,
+                {
+
+                    unsafe {
+                        let ptr = lvgl_sys::lv_arc_create(parent.raw()?.as_mut(), core::ptr::null_mut());
+                        if let Some(raw) = core::ptr::NonNull::new(ptr) {
+                            let core = <crate::Obj as crate::Widget>::from_raw(raw);
+                            Ok(Self { core })
+                        } else {
+                            Err(crate::LvError::InvalidReference)
+                        }
+                    }
+                }
+            }
+        };
+
+        assert_eq!(code.to_string(), expected_code.to_string());
+    }
+}

lvgl-sys/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "lvgl-sys"
-description = "Raw bindings to the LittlevGL C library."
-version = "0.2.0"
+description = "Raw bindings to the LVGL C library."
+version = "0.5.2"
 authors = ["Rafael Caricio <crates.lvgl-sys@caric.io>"]
 edition = "2018"
 license = "MIT"
@@ -20,5 +20,8 @@ name = "lvgl_sys"
 cty = "0.2.1"
 
 [build-dependencies]
-cc = "1.0.50"
-bindgen = "0.53.2"
+cc = "1.0.68"
+bindgen = "0.59.2"
+
+[features]
+use-vendored-config = []

lvgl-sys/README.md

@@ -5,7 +5,7 @@ Rust raw bindings for LittlevGL library.
 
 Build requires environment variables to be set:
 
-- `DEP_LV_CONFIG_PATH`: Path to the directory containing the `lv_conf.h` header file used for configuration of LittlevGL library.
+- `DEP_LV_CONFIG_PATH`: Path to the directory containing the `lv_conf.h` header file used for configuration of LVGL library.
 
 We recommend the `lv_conf.h` file to be in your project's root directory. If so, the command to build your project would be:
 ```shell script

lvgl-sys/build.rs

@@ -1,41 +1,53 @@
-use bindgen;
 use cc::Build;
 use std::{env, path::Path, path::PathBuf};
 
 static CONFIG_NAME: &str = "DEP_LV_CONFIG_PATH";
 
 fn main() {
-    let project_dir = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap())
-        .canonicalize()
-        .unwrap();
+    let project_dir = canonicalize(PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap()));
     let shims_dir = project_dir.join("shims");
     let vendor = project_dir.join("vendor");
     let vendor_src = vendor.join("lvgl").join("src");
 
     let lv_config_dir = {
-        let raw_path = env::var(CONFIG_NAME).expect(
-            format!(
-                "The environment variable {} is required to be defined",
-                CONFIG_NAME
-            )
-            .as_str(),
-        );
-        let conf_path = PathBuf::from(raw_path);
+        let conf_path = env::var(CONFIG_NAME)
+            .map(PathBuf::from)
+            .unwrap_or_else(|_| {
+                match std::env::var("DOCS_RS") {
+                    Ok(_) => {
+                        // We've detected that we are building for docs.rs
+                        // so let's use the vendored `lv_conf.h` file.
+                        vendor.join("include")
+                    }
+                    Err(_) => {
+                        #[cfg(not(feature = "use-vendored-config"))]
+                        panic!(
+                            "The environment variable {} is required to be defined",
+                            CONFIG_NAME
+                        );
+
+                        #[cfg(feature = "use-vendored-config")]
+                        vendor.join("include")
+                    }
+                }
+            });
 
         if !conf_path.exists() {
-            panic!(format!(
-                "Directory referenced by {} needs to exist",
+            panic!(
+                "Directory {} referenced by {} needs to exist",
+                conf_path.to_string_lossy(),
                 CONFIG_NAME
-            ));
+            );
         }
         if !conf_path.is_dir() {
-            panic!(format!("{} needs to be a directory", CONFIG_NAME));
+            panic!("{} needs to be a directory", CONFIG_NAME);
         }
         if !conf_path.join("lv_conf.h").exists() {
-            panic!(format!(
-                "Directory referenced by {} needs to contain a file called lv_conf.h",
+            panic!(
+                "Directory {} referenced by {} needs to contain a file called lv_conf.h",
+                conf_path.to_string_lossy(),
                 CONFIG_NAME
-            ));
+            );
         }
 
         println!(
@@ -49,41 +61,73 @@ fn main() {
     add_c_files(&mut cfg, vendor_src.join("lv_core"));
     add_c_files(&mut cfg, vendor_src.join("lv_draw"));
     add_c_files(&mut cfg, vendor_src.join("lv_font"));
+    add_c_files(&mut cfg, vendor_src.join("lv_gpu"));
     add_c_files(&mut cfg, vendor_src.join("lv_hal"));
     add_c_files(&mut cfg, vendor_src.join("lv_misc"));
-    add_c_files(&mut cfg, vendor_src.join("lv_objx"));
-    add_c_files(&mut cfg, vendor_src.join("lv_themes"));
     add_c_files(&mut cfg, vendor_src.join("lv_themes"));
+    add_c_files(&mut cfg, vendor_src.join("lv_widgets"));
     add_c_files(&mut cfg, &lv_config_dir);
     add_c_files(&mut cfg, &shims_dir);
 
     cfg.define("LV_CONF_INCLUDE_SIMPLE", Some("1"))
         .include(&vendor_src)
         .include(&vendor)
-        .file("string.c")
         .warnings(false)
         .include(&lv_config_dir)
         .compile("lvgl");
 
-    let cc_args = [
+    let mut cc_args = vec![
         "-DLV_CONF_INCLUDE_SIMPLE=1",
         "-I",
         lv_config_dir.to_str().unwrap(),
         "-I",
         vendor.to_str().unwrap(),
+        "-fvisibility=default",
     ];
 
+    // Set correct target triple for bindgen when cross-compiling
+    let target = env::var("TARGET").expect("Cargo build scripts always have TARGET");
+    let host = env::var("HOST").expect("Cargo build scripts always have HOST");
+    if target != host {
+        cc_args.push("-target");
+        cc_args.push(target.as_str());
+    }
+
+    let mut additional_args = Vec::new();
+    if target.ends_with("emscripten") {
+        if let Ok(em_path) = env::var("EMSDK") {
+            additional_args.push("-I".to_string());
+            additional_args.push(format!(
+                "{}/upstream/emscripten/system/include/libc",
+                em_path
+            ));
+            additional_args.push("-I".to_string());
+            additional_args.push(format!(
+                "{}/upstream/emscripten/system/lib/libc/musl/arch/emscripten",
+                em_path
+            ));
+            additional_args.push("-I".to_string());
+            additional_args.push(format!(
+                "{}/upstream/emscripten/system/include/SDL",
+                em_path
+            ));
+        }
+    }
+
     let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
-    bindgen::Builder::default()
+    let bindings = bindgen::Builder::default()
         .header(shims_dir.join("lvgl_sys.h").to_str().unwrap())
+        .generate_comments(false)
         .layout_tests(false)
         .use_core()
         .rustfmt_bindings(true)
         .ctypes_prefix("cty")
-        .raw_line("use cty;")
         .clang_args(&cc_args)
+        .clang_args(&additional_args)
         .generate()
-        .expect("Unable to generate bindings")
+        .expect("Unable to generate bindings");
+
+    bindings
         .write_to_file(out_path.join("bindings.rs"))
         .expect("Can't write bindings!");
 }
@@ -99,3 +143,10 @@ fn add_c_files(build: &mut cc::Build, path: impl AsRef<Path>) {
         }
     }
 }
+
+fn canonicalize(path: impl AsRef<Path>) -> PathBuf {
+    let canonicalized = path.as_ref().canonicalize().unwrap();
+    let canonicalized = &*canonicalized.to_string_lossy();
+
+    PathBuf::from(canonicalized.strip_prefix(r"\\?\").unwrap_or(canonicalized))
+}

lvgl-sys/src/lib.rs

@@ -2,9 +2,17 @@
 #![allow(non_snake_case)]
 #![allow(non_camel_case_types)]
 #![allow(non_upper_case_globals)]
+#![allow(clippy::too_many_arguments)]
+#![allow(clippy::redundant_static_lifetimes)]
 
 include!(concat!(env!("OUT_DIR"), "/bindings.rs"));
 
+pub fn _bindgen_raw_src() -> &'static str {
+    include_str!(concat!(env!("OUT_DIR"), "/bindings.rs"))
+}
+
+mod string_impl;
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -14,11 +22,11 @@ mod tests {
         unsafe {
             lv_init();
 
-            let horizontal_resolution = lv_disp_get_hor_res(std::ptr::null_mut());
-            assert_eq!(horizontal_resolution, 480);
+            let horizontal_resolution = lv_disp_get_hor_res(core::ptr::null_mut());
+            assert_eq!(horizontal_resolution, LV_HOR_RES_MAX as i16);
 
-            let vertical_resolution = lv_disp_get_ver_res(std::ptr::null_mut());
-            assert_eq!(vertical_resolution, 320);
+            let vertical_resolution = lv_disp_get_ver_res(core::ptr::null_mut());
+            assert_eq!(vertical_resolution, LV_VER_RES_MAX as i16);
         }
     }
 }

lvgl-sys/src/string_impl.rs

@@ -0,0 +1,159 @@
+// MIT License
+//
+// Copyright (c) 2018 Redox OS
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+use core::{ptr, usize};
+use cty::*;
+
+#[no_mangle]
+pub unsafe extern "C" fn strchr(mut s: *const c_char, c: c_int) -> *mut c_char {
+    let c = c as c_char;
+    while *s != 0 {
+        if *s == c {
+            return s as *mut c_char;
+        }
+        s = s.offset(1);
+    }
+    ptr::null_mut()
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn strcmp(s1: *const c_char, s2: *const c_char) -> c_int {
+    strncmp(s1, s2, usize::MAX)
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn strcoll(s1: *const c_char, s2: *const c_char) -> c_int {
+    // relibc has no locale stuff (yet)
+    strcmp(s1, s2)
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn strcpy(dst: *mut c_char, src: *const c_char) -> *mut c_char {
+    let mut i = 0;
+
+    loop {
+        let byte = *src.offset(i);
+        *dst.offset(i) = byte;
+
+        if byte == 0 {
+            break;
+        }
+
+        i += 1;
+    }
+
+    dst
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn strlen(s: *const c_char) -> size_t {
+    strnlen(s, usize::MAX)
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn strnlen(s: *const c_char, size: size_t) -> size_t {
+    let mut i = 0;
+    while i < size {
+        if *s.add(i) == 0 {
+            break;
+        }
+        i += 1;
+    }
+    i as size_t
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn strnlen_s(s: *const c_char, size: size_t) -> size_t {
+    if s.is_null() {
+        0
+    } else {
+        strnlen(s, size)
+    }
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn strcat(s1: *mut c_char, s2: *const c_char) -> *mut c_char {
+    strncat(s1, s2, usize::MAX)
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn strncat(s1: *mut c_char, s2: *const c_char, n: size_t) -> *mut c_char {
+    let len = strlen(s1 as *const c_char);
+    let mut i = 0;
+    while i < n {
+        let b = *s2.add(i);
+        if b == 0 {
+            break;
+        }
+
+        *s1.add(len + i) = b;
+        i += 1;
+    }
+    *s1.add(len + i) = 0;
+
+    s1
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn strncmp(s1: *const c_char, s2: *const c_char, n: size_t) -> c_int {
+    let s1 = core::slice::from_raw_parts(s1 as *const c_uchar, n);
+    let s2 = core::slice::from_raw_parts(s2 as *const c_uchar, n);
+
+    for (&a, &b) in s1.iter().zip(s2.iter()) {
+        let val = (a as c_int) - (b as c_int);
+        if a != b || a == 0 {
+            return val;
+        }
+    }
+
+    0
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn strncpy(dst: *mut c_char, src: *const c_char, n: size_t) -> *mut c_char {
+    let mut i = 0;
+
+    while *src.add(i) != 0 && i < n {
+        *dst.add(i) = *src.add(i);
+        i += 1;
+    }
+
+    for i in i..n {
+        *dst.add(i) = 0;
+    }
+
+    dst
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn strrchr(s: *const c_char, c: c_int) -> *mut c_char {
+    let len = strlen(s) as isize;
+    let c = c as c_char;
+    let mut i = len - 1;
+    while i >= 0 {
+        if *s.offset(i) == c {
+            return s.offset(i) as *mut c_char;
+        }
+        i -= 1;
+    }
+    ptr::null_mut()
+}

lvgl-sys/string.c

@@ -1,68 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- *  linux/lib/string.c
- *
- *  Copyright (C) 1991, 1992  Linus Torvalds
- */
-
-#include <string.h>
-
-size_t strspn(const char *s, const char *accept)
-{
-    const char *p;
-    const char *a;
-    size_t count = 0;
-
-    for (p = s; *p != '\0'; ++p) {
-        for (a = accept; *a != '\0'; ++a) {
-            if (*p == *a)
-                break;
-        }
-        if (*a == '\0')
-            return count;
-        ++count;
-    }
-    return count;
-}
-
-size_t strcspn(const char *s, const char *reject)
-{
-    const char *p;
-    const char *r;
-    size_t count = 0;
-
-    for (p = s; *p != '\0'; ++p) {
-        for (r = reject; *r != '\0'; ++r) {
-            if (*p == *r)
-                return count;
-        }
-        ++count;
-    }
-    return count;
-}
-
-size_t strlen(const char *s)
-{
-    const char *sc;
-
-    for (sc = s; *sc != '\0'; ++sc)
-        /* nothing */;
-    return sc - s;
-}
-
-char *strchr(const char *s, int c)
-{
-    for (; *s != (char)c; ++s)
-        if (*s == '\0')
-            return NULL;
-    return (char *)s;
-}
-
-char *strcpy(char *dest, const char *src)
-{
-    char *tmp = dest;
-
-    while ((*dest++ = *src++) != '\0')
-        /* nothing */;
-    return tmp;
-}

lvgl-sys/vendor/include/lv_conf.h

@@ -1,3 +1,14 @@
+/**
+ * @file lv_conf.h
+ *
+ */
+
+/*
+ * COPY THIS FILE AS `lv_conf.h` NEXT TO the `lvgl` FOLDER
+ */
+
+#if 1 /*Set it to "1" to enable content*/
+
 #ifndef LV_CONF_H
 #define LV_CONF_H
 /* clang-format off */
@@ -14,7 +25,7 @@
 
 /* Color depth:
  * - 1:  1 byte per pixel
- * - 8:  RGB233
+ * - 8:  RGB332
  * - 16: RGB565
  * - 32: ARGB8888
  */
@@ -32,9 +43,6 @@
 /*Images pixels with this color will not be drawn (with chroma keying)*/
 #define LV_COLOR_TRANSP    LV_COLOR_LIME         /*LV_COLOR_LIME: pure green*/
 
-/* Enable chroma keying for indexed images. */
-#define LV_INDEXED_CHROMA    1
-
 /* Enable anti-aliasing (lines, and radiuses will be smoothed) */
 #define LV_ANTIALIAS        1
 
@@ -45,7 +53,18 @@
 /* Dot Per Inch: used to initialize default sizes.
  * E.g. a button with width = LV_DPI / 2 -> half inch wide
  * (Not so important, you can adjust it to modify default sizes and spaces)*/
-#define LV_DPI              298     /*[px]*/
+#define LV_DPI              130     /*[px]*/
+
+/* The the real width of the display changes some default values:
+ * default object sizes, layout of examples, etc.
+ * According to the width of the display (hor. res. / dpi)
+ * the displays fall in 4 categories.
+ * The 4th is extra large which has no upper limit so not listed here
+ * The upper limit of the categories are set below in 0.1 inch unit.
+ */
+#define LV_DISP_SMALL_LIMIT  30
+#define LV_DISP_MEDIUM_LIMIT 50
+#define LV_DISP_LARGE_LIMIT  70
 
 /* Type of coordinates. Should be `int16_t` (or `int32_t` for extreme cases) */
 typedef int16_t lv_coord_t;
@@ -61,7 +80,7 @@ typedef int16_t lv_coord_t;
 #define LV_MEM_CUSTOM      0
 #if LV_MEM_CUSTOM == 0
 /* Size of the memory used by `lv_mem_alloc` in bytes (>= 2kB)*/
-#  define LV_MEM_SIZE    (4U * 1024U)
+#  define LV_MEM_SIZE    (32U * 1024U)
 
 /* Complier prefix for a big array declaration */
 #  define LV_MEM_ATTR
@@ -101,7 +120,7 @@ typedef int16_t lv_coord_t;
 #define LV_INDEV_DEF_DRAG_LIMIT           10
 
 /* Drag throw slow-down in [%]. Greater value -> faster slow-down */
-#define LV_INDEV_DEF_DRAG_THROW           20
+#define LV_INDEV_DEF_DRAG_THROW           10
 
 /* Long press time in milliseconds.
  * Time to send `LV_EVENT_LONG_PRESSSED`) */
@@ -111,6 +130,13 @@ typedef int16_t lv_coord_t;
  * Time between `LV_EVENT_LONG_PRESSED_REPEAT */
 #define LV_INDEV_DEF_LONG_PRESS_REP_TIME  100
 
+
+/* Gesture threshold in pixels */
+#define LV_INDEV_DEF_GESTURE_LIMIT        50
+
+/* Gesture min velocity at release before swipe (pixels)*/
+#define LV_INDEV_DEF_GESTURE_MIN_VELOCITY 3
+
 /*==================
  * Feature usage
  *==================*/
@@ -126,6 +152,22 @@ typedef void * lv_anim_user_data_t;
 
 /* 1: Enable shadow drawing*/
 #define LV_USE_SHADOW           1
+#if LV_USE_SHADOW
+/* Allow buffering some shadow calculation
+ * LV_SHADOW_CACHE_SIZE is the max. shadow size to buffer,
+ * where shadow size is `shadow_width + radius`
+ * Caching has LV_SHADOW_CACHE_SIZE^2 RAM cost*/
+#define LV_SHADOW_CACHE_SIZE    0
+#endif
+
+/* 1: Use other blend modes than normal (`LV_BLEND_MODE_...`)*/
+#define LV_USE_BLEND_MODES      1
+
+/* 1: Use the `opa_scale` style property to set the opacity of an object and its children at once*/
+#define LV_USE_OPA_SCALE        1
+
+/* 1: Use image zoom and rotation*/
+#define LV_USE_IMG_TRANSFORM    1
 
 /* 1: Enable object groups (for keyboard/encoder navigation) */
 #define LV_USE_GROUP            1
@@ -134,10 +176,11 @@ typedef void * lv_group_user_data_t;
 #endif  /*LV_USE_GROUP*/
 
 /* 1: Enable GPU interface*/
-#define LV_USE_GPU              0
+#define LV_USE_GPU              1   /*Only enables `gpu_fill_cb` and `gpu_blend_cb` in the disp. drv- */
+#define LV_USE_GPU_STM32_DMA2D  0
 
 /* 1: Enable file system (might be required for images */
-#define LV_USE_FILESYSTEM       0
+#define LV_USE_FILESYSTEM       1
 #if LV_USE_FILESYSTEM
 /*Declare the type of the user data of file system drivers (can be e.g. `void *`, `int`, `struct`)*/
 typedef void * lv_fs_drv_user_data_t;
@@ -146,6 +189,12 @@ typedef void * lv_fs_drv_user_data_t;
 /*1: Add a `user_data` to drivers and objects*/
 #define LV_USE_USER_DATA        1
 
+/*1: Show CPU usage and FPS count in the right bottom corner*/
+#define LV_USE_PERF_MONITOR     0
+
+/*1: Use the functions and types from the older API if possible */
+#define LV_USE_API_EXTENSION_V6  1
+
 /*========================
  * Image decoder and cache
  *========================*/
@@ -176,6 +225,9 @@ typedef void * lv_img_decoder_user_data_t;
 /* Define a custom attribute to `lv_task_handler` function */
 #define LV_ATTRIBUTE_TASK_HANDLER
 
+/* Define a custom attribute to `lv_disp_flush_ready` function */
+#define LV_ATTRIBUTE_FLUSH_READY
+
 /* With size optimization (-Os) the compiler might not align data to
  * 4 or 8 byte boundary. This alignment will be explicitly applied where needed.
  * E.g. __attribute__((aligned(4))) */
@@ -185,6 +237,10 @@ typedef void * lv_img_decoder_user_data_t;
  * font's bitmaps */
 #define LV_ATTRIBUTE_LARGE_CONST
 
+/* Prefix performance critical functions to place them into a faster memory (e.g RAM)
+ * Uses 15-20 kB extra memory */
+#define LV_ATTRIBUTE_FAST_MEM
+
 /* Export integer constant to binding.
  * This macro is used with constants in the form of LV_<CONST> that
  * should also appear on lvgl binding API such as Micropython
@@ -242,7 +298,7 @@ typedef void * lv_indev_drv_user_data_t;            /*Type of user data in the i
  * The behavior of asserts can be overwritten by redefining them here.
  * E.g. #define LV_ASSERT_MEM(p)  <my_assert_code>
  */
-#define LV_USE_DEBUG        0
+#define LV_USE_DEBUG        1
 #if LV_USE_DEBUG
 
 /*Check if the parameter is NULL. (Quite fast) */
@@ -251,6 +307,9 @@ typedef void * lv_indev_drv_user_data_t;            /*Type of user data in the i
 /*Checks is the memory is successfully allocated or no. (Quite fast)*/
 #define LV_USE_ASSERT_MEM       1
 
+/*Check the integrity of `lv_mem` after critical operations. (Slow)*/
+#define LV_USE_ASSERT_MEM_INTEGRITY       0
+
 /* Check the strings.
  * Search for NULL, very long strings, invalid characters, and unnatural repetitions. (Slow)
  * If disabled `LV_USE_ASSERT_NULL` will be performed instead (if it's enabled) */
@@ -261,44 +320,47 @@ typedef void * lv_indev_drv_user_data_t;            /*Type of user data in the i
 #define LV_USE_ASSERT_OBJ       0
 
 /*Check if the styles are properly initialized. (Fast)*/
-#define LV_USE_ASSERT_STYLE     1
+#define LV_USE_ASSERT_STYLE     0
 
 #endif /*LV_USE_DEBUG*/
 
-/*================
- *  THEME USAGE
- *================*/
-#define LV_THEME_LIVE_UPDATE    0   /*1: Allow theme switching at run time. Uses 8..10 kB of RAM*/
-
-#define LV_USE_THEME_TEMPL      0   /*Just for test*/
-#define LV_USE_THEME_DEFAULT    0   /*Built mainly from the built-in styles. Consumes very few RAM*/
-#define LV_USE_THEME_ALIEN      0   /*Dark futuristic theme*/
-#define LV_USE_THEME_NIGHT      0   /*Dark elegant theme*/
-#define LV_USE_THEME_MONO       0   /*Mono color theme for monochrome displays*/
-#define LV_USE_THEME_MATERIAL   0   /*Flat theme with bold colors and light shadows*/
-#define LV_USE_THEME_ZEN        0   /*Peaceful, mainly light theme */
-#define LV_USE_THEME_NEMO       0   /*Water-like theme based on the movie "Finding Nemo"*/
-
 /*==================
  *    FONT USAGE
  *===================*/
 
 /* The built-in fonts contains the ASCII range and some Symbols with  4 bit-per-pixel.
  * The symbols are available via `LV_SYMBOL_...` defines
- * More info about fonts: https://docs.littlevgl.com/#Fonts
- * To create a new font go to: https://littlevgl.com/ttf-font-to-c-array
+ * More info about fonts: https://docs.lvgl.com/#Fonts
+ * To create a new font go to: https://lvgl.com/ttf-font-to-c-array
  */
 
-/* Robot fonts with bpp = 4
- * https://fonts.google.com/specimen/Roboto  */
-#define LV_FONT_ROBOTO_12    0
-#define LV_FONT_ROBOTO_16    0
-#define LV_FONT_ROBOTO_22    0
-#define LV_FONT_ROBOTO_28    1
+/* Montserrat fonts with bpp = 4
+ * https://fonts.google.com/specimen/Montserrat  */
+#define LV_FONT_MONTSERRAT_12    0
+#define LV_FONT_MONTSERRAT_14    0
+#define LV_FONT_MONTSERRAT_16    1
+#define LV_FONT_MONTSERRAT_18    0
+#define LV_FONT_MONTSERRAT_20    0
+#define LV_FONT_MONTSERRAT_22    0
+#define LV_FONT_MONTSERRAT_24    0
+#define LV_FONT_MONTSERRAT_26    0
+#define LV_FONT_MONTSERRAT_28    0
+#define LV_FONT_MONTSERRAT_30    0
+#define LV_FONT_MONTSERRAT_32    0
+#define LV_FONT_MONTSERRAT_34    0
+#define LV_FONT_MONTSERRAT_36    0
+#define LV_FONT_MONTSERRAT_38    0
+#define LV_FONT_MONTSERRAT_40    0
+#define LV_FONT_MONTSERRAT_42    0
+#define LV_FONT_MONTSERRAT_44    0
+#define LV_FONT_MONTSERRAT_46    0
+#define LV_FONT_MONTSERRAT_48    0
 
 /* Demonstrate special features */
-#define LV_FONT_ROBOTO_12_SUBPX 1
-#define LV_FONT_ROBOTO_28_COMPRESSED 1  /*bpp = 3*/
+#define LV_FONT_MONTSERRAT_12_SUBPX      0
+#define LV_FONT_MONTSERRAT_28_COMPRESSED 0  /*bpp = 3*/
+#define LV_FONT_DEJAVU_16_PERSIAN_HEBREW 0  /*Hebrew, Arabic, PErisan letters and all their forms*/
+#define LV_FONT_SIMSUN_16_CJK            0  /*1000 most common CJK radicals*/
 
 /*Pixel perfect monospace font
  * http://pelulamu.net/unscii/ */
@@ -312,9 +374,6 @@ typedef void * lv_indev_drv_user_data_t;            /*Type of user data in the i
  */
 #define LV_FONT_CUSTOM_DECLARE
 
-/*Always set a default font from the built-in fonts*/
-#define LV_FONT_DEFAULT        &lv_font_roboto_28
-
 /* Enable it if you have fonts with a lot of characters.
  * The limit depends on the font size, font face and bpp
  * but with > 10,000 characters if you see issues probably you need to enable it.*/
@@ -329,6 +388,43 @@ typedef void * lv_indev_drv_user_data_t;            /*Type of user data in the i
 /*Declare the type of the user data of fonts (can be e.g. `void *`, `int`, `struct`)*/
 typedef void * lv_font_user_data_t;
 
+/*================
+ *  THEME USAGE
+ *================*/
+
+/*Always enable at least on theme*/
+
+/* No theme, you can apply your styles as you need
+ * No flags. Set LV_THEME_DEFAULT_FLAG 0 */
+ #define LV_USE_THEME_EMPTY       1
+
+/*Simple to the create your theme based on it
+ * No flags. Set LV_THEME_DEFAULT_FLAG 0 */
+ #define LV_USE_THEME_TEMPLATE    1
+
+/* A fast and impressive theme.
+ * Flags:
+ * LV_THEME_MATERIAL_FLAG_LIGHT: light theme
+ * LV_THEME_MATERIAL_FLAG_DARK: dark theme*/
+ #define LV_USE_THEME_MATERIAL    1
+
+/* Mono-color theme for monochrome displays.
+ * If LV_THEME_DEFAULT_COLOR_PRIMARY is LV_COLOR_BLACK the
+ * texts and borders will be black and the background will be
+ * white. Else the colors are inverted.
+ * No flags. Set LV_THEME_DEFAULT_FLAG 0 */
+ #define LV_USE_THEME_MONO        1
+
+#define LV_THEME_DEFAULT_INCLUDE            <stdint.h>      /*Include a header for the init. function*/
+#define LV_THEME_DEFAULT_INIT               lv_theme_material_init
+#define LV_THEME_DEFAULT_COLOR_PRIMARY      LV_COLOR_RED
+#define LV_THEME_DEFAULT_COLOR_SECONDARY    LV_COLOR_BLUE
+#define LV_THEME_DEFAULT_FLAG               LV_THEME_MATERIAL_FLAG_LIGHT
+#define LV_THEME_DEFAULT_FONT_SMALL         &lv_font_montserrat_16
+#define LV_THEME_DEFAULT_FONT_NORMAL        &lv_font_montserrat_16
+#define LV_THEME_DEFAULT_FONT_SUBTITLE      &lv_font_montserrat_16
+#define LV_THEME_DEFAULT_FONT_TITLE         &lv_font_montserrat_16
+
 /*=================
  *  Text settings
  *=================*/
@@ -340,13 +436,12 @@ typedef void * lv_font_user_data_t;
  * */
 #define LV_TXT_ENC LV_TXT_ENC_UTF8
 
-/*Can break (wrap) texts on these chars*/
+ /*Can break (wrap) texts on these chars*/
 #define LV_TXT_BREAK_CHARS                  " ,.;:-_"
 
-
 /* If a word is at least this long, will break wherever "prettiest"
  * To disable, set to a value <= 0 */
-#define LV_TXT_LINE_BREAK_LONG_LEN          12
+#define LV_TXT_LINE_BREAK_LONG_LEN          0
 
 /* Minimum number of characters in a long word to put on a line before a break.
  * Depends on LV_TXT_LINE_BREAK_LONG_LEN. */
@@ -372,20 +467,36 @@ typedef void * lv_font_user_data_t;
 #define LV_BIDI_BASE_DIR_DEF  LV_BIDI_DIR_AUTO
 #endif
 
+/* Enable Arabic/Persian processing
+ * In these languages characters should be replaced with
+ * an other form based on their position in the text */
+#define LV_USE_ARABIC_PERSIAN_CHARS 0
+
 /*Change the built in (v)snprintf functions*/
 #define LV_SPRINTF_CUSTOM   0
 #if LV_SPRINTF_CUSTOM
 #  define LV_SPRINTF_INCLUDE <stdio.h>
 #  define lv_snprintf     snprintf
 #  define lv_vsnprintf    vsnprintf
+#else   /*!LV_SPRINTF_CUSTOM*/
+#  define LV_SPRINTF_DISABLE_FLOAT 1
 #endif  /*LV_SPRINTF_CUSTOM*/
 
 /*===================
  *  LV_OBJ SETTINGS
  *==================*/
 
+#if LV_USE_USER_DATA
 /*Declare the type of the user data of object (can be e.g. `void *`, `int`, `struct`)*/
 typedef void * lv_obj_user_data_t;
+/*Provide a function to free user data*/
+#define LV_USE_USER_DATA_FREE 0
+#if LV_USE_USER_DATA_FREE
+#  define LV_USER_DATA_FREE_INCLUDE  "something.h"  /*Header for user data free function*/
+/* Function prototype : void user_data_free(lv_obj_t * obj); */
+#  define LV_USER_DATA_FREE  (user_data_free)       /*Invoking for user data free function*/
+#endif
+#endif
 
 /*1: enable `lv_obj_realaign()` based on `lv_obj_align()` parameters*/
 #define LV_USE_OBJ_REALIGN          1
@@ -395,13 +506,13 @@ typedef void * lv_obj_user_data_t;
  * LV_EXT_CLICK_AREA_TINY: The extra area can be adjusted horizontally and vertically (0..255 px)
  * LV_EXT_CLICK_AREA_FULL: The extra area can be adjusted in all 4 directions (-32k..+32k px)
  */
-#define LV_USE_EXT_CLICK_AREA  LV_EXT_CLICK_AREA_OFF
+#define LV_USE_EXT_CLICK_AREA  LV_EXT_CLICK_AREA_TINY
 
 /*==================
  *  LV OBJ X USAGE
  *================*/
 /*
- * Documentation of the object types: https://docs.littlevgl.com/#Object-types
+ * Documentation of the object types: https://docs.lvgl.com/#Object-types
  */
 
 /*Arc (dependencies: -)*/
@@ -412,13 +523,9 @@ typedef void * lv_obj_user_data_t;
 
 /*Button (dependencies: lv_cont*/
 #define LV_USE_BTN      1
-#if LV_USE_BTN != 0
-/*Enable button-state animations - draw a circle on click (dependencies: LV_USE_ANIMATION)*/
-#  define LV_BTN_INK_EFFECT   0
-#endif
 
 /*Button matrix (dependencies: -)*/
-#define LV_USE_BTNM     1
+#define LV_USE_BTNMATRIX     1
 
 /*Calendar (dependencies: -)*/
 #define LV_USE_CALENDAR 1
@@ -427,12 +534,12 @@ typedef void * lv_obj_user_data_t;
 #define LV_USE_CANVAS   1
 
 /*Check box (dependencies: lv_btn, lv_label)*/
-#define LV_USE_CB       1
+#define LV_USE_CHECKBOX       1
 
 /*Chart (dependencies: -)*/
 #define LV_USE_CHART    1
 #if LV_USE_CHART
-#  define LV_CHART_AXIS_TICK_LABEL_MAX_LEN    20
+#  define LV_CHART_AXIS_TICK_LABEL_MAX_LEN    256
 #endif
 
 /*Container (dependencies: -*/
@@ -442,13 +549,13 @@ typedef void * lv_obj_user_data_t;
 #define LV_USE_CPICKER   1
 
 /*Drop down list (dependencies: lv_page, lv_label, lv_symbol_def.h)*/
-#define LV_USE_DDLIST    1
-#if LV_USE_DDLIST != 0
+#define LV_USE_DROPDOWN    1
+#if LV_USE_DROPDOWN != 0
 /*Open and close default animation time [ms] (0: no animation)*/
-#  define LV_DDLIST_DEF_ANIM_TIME     200
+#  define LV_DROPDOWN_DEF_ANIM_TIME     200
 #endif
 
-/*Gauge (dependencies:lv_bar, lv_lmeter)*/
+/*Gauge (dependencies:lv_bar, lv_linemeter)*/
 #define LV_USE_GAUGE    1
 
 /*Image (dependencies: lv_label*/
@@ -462,7 +569,7 @@ typedef void * lv_obj_user_data_t;
 #endif
 
 /*Keyboard (dependencies: lv_btnm)*/
-#define LV_USE_KB       1
+#define LV_USE_KEYBOARD       1
 
 /*Label (dependencies: -*/
 #define LV_USE_LABEL    1
@@ -482,6 +589,10 @@ typedef void * lv_obj_user_data_t;
 
 /*LED (dependencies: -)*/
 #define LV_USE_LED      1
+#if LV_USE_LED
+#  define LV_LED_BRIGHT_MIN  120      /*Minimal brightness*/
+#  define LV_LED_BRIGHT_MAX  255     /*Maximal brightness*/
+#endif
 
 /*Line (dependencies: -*/
 #define LV_USE_LINE     1
@@ -494,10 +605,22 @@ typedef void * lv_obj_user_data_t;
 #endif
 
 /*Line meter (dependencies: *;)*/
-#define LV_USE_LMETER   1
+#define LV_USE_LINEMETER   1
+#if LV_USE_LINEMETER
+/* Draw line more precisely at cost of performance.
+ * Useful if there are lot of lines any minor are visible
+ * 0: No extra precision
+ * 1: Some extra precision
+ * 2: Best precision
+ */
+#  define LV_LINEMETER_PRECISE    0
+#endif
+
+/*Mask (dependencies: -)*/
+#define LV_USE_OBJMASK  1
 
 /*Message box (dependencies: lv_rect, lv_btnm, lv_label)*/
-#define LV_USE_MBOX     1
+#define LV_USE_MSGBOX     1
 
 /*Page (dependencies: lv_cont)*/
 #define LV_USE_PAGE     1
@@ -507,11 +630,11 @@ typedef void * lv_obj_user_data_t;
 #endif
 
 /*Preload (dependencies: lv_arc, lv_anim)*/
-#define LV_USE_PRELOAD      1
-#if LV_USE_PRELOAD != 0
-#  define LV_PRELOAD_DEF_ARC_LENGTH   60      /*[deg]*/
-#  define LV_PRELOAD_DEF_SPIN_TIME    1000    /*[ms]*/
-#  define LV_PRELOAD_DEF_ANIM         LV_PRELOAD_TYPE_SPINNING_ARC
+#define LV_USE_SPINNER      1
+#if LV_USE_SPINNER != 0
+#  define LV_SPINNER_DEF_ARC_LENGTH   60      /*[deg]*/
+#  define LV_SPINNER_DEF_SPIN_TIME    1000    /*[ms]*/
+#  define LV_SPINNER_DEF_ANIM         LV_SPINNER_TYPE_SPINNING_ARC
 #endif
 
 /*Roller (dependencies: lv_ddlist)*/
@@ -531,13 +654,13 @@ typedef void * lv_obj_user_data_t;
 #define LV_USE_SPINBOX       1
 
 /*Switch (dependencies: lv_slider)*/
-#define LV_USE_SW       1
+#define LV_USE_SWITCH       1
 
 /*Text area (dependencies: lv_label, lv_page)*/
-#define LV_USE_TA       1
-#if LV_USE_TA != 0
-#  define LV_TA_DEF_CURSOR_BLINK_TIME 400     /*ms*/
-#  define LV_TA_DEF_PWD_SHOW_TIME     1500    /*ms*/
+#define LV_USE_TEXTAREA       1
+#if LV_USE_TEXTAREA != 0
+#  define LV_TEXTAREA_DEF_CURSOR_BLINK_TIME 400     /*ms*/
+#  define LV_TEXTAREA_DEF_PWD_SHOW_TIME     1500    /*ms*/
 #endif
 
 /*Table (dependencies: lv_label)*/
@@ -573,7 +696,6 @@ typedef void * lv_obj_user_data_t;
 
 /*--END OF LV_CONF_H--*/
 
-/*Be sure every define has a default value*/
-#include "lvgl/src/lv_conf_checker.h"
-
 #endif /*LV_CONF_H*/
+
+#endif /*End of "Content enable"*/

lvgl-sys/vendor/lvgl

@@ -1 +1 @@
-Subproject commit 9eeaf61fa7ec2b5ea151374b135b85f15438938c
+Subproject commit 524709472757405ac0eef8d6d002632526430df3

lvgl/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "lvgl"
-description = "LittlevGL bindings for Rust. A powerful and easy-to-use embedded GUI with many widgets, advanced visual effects (opacity, antialiasing, animations) and low memory requirements (16K RAM, 64K Flash)."
-version = "0.2.1"
+description = "LVGL bindings for Rust. A powerful and easy-to-use embedded GUI with many widgets, advanced visual effects (opacity, antialiasing, animations) and low memory requirements (16K RAM, 64K Flash)."
+version = "0.5.2"
 authors = ["Rafael Caricio <crates.lvgl@caric.io>"]
 edition = "2018"
 repository = "https://github.com/rafaelcaricio/lvgl-rs"
@@ -9,9 +9,50 @@ license = "MIT"
 readme = "../README.md"
 categories = ["api-bindings", "embedded", "gui", "no-std"]
 keywords = ["littlevgl", "lvgl", "graphical_interfaces"]
+build = "build.rs"
 
 [dependencies]
-lvgl-sys = { path = "../lvgl-sys", version = "0.2.0" }
+lvgl-sys = { version = "0.5.2", path = "../lvgl-sys" }
 cty = "0.2.1"
-embedded-graphics = "0.6.2"
-cstr_core = { version = "0.2.0", default-features = false, features = ["alloc"] }
+embedded-graphics = "0.7.1"
+cstr_core = "0.2.3"
+bitflags = "1.2.1"
+
+[features]
+alloc = ["cstr_core/alloc"]
+lvgl_alloc = ["alloc"]
+use-vendored-config = ["lvgl-sys/use-vendored-config"]
+
+[build-dependencies]
+quote = "1.0.9"
+proc-macro2 = "1.0.24"
+lvgl-codegen = { version = "0.5.2", path = "../lvgl-codegen" }
+lvgl-sys = { version = "0.5.2", path = "../lvgl-sys" }
+
+[dev-dependencies]
+embedded-graphics-simulator = "0.3.0"
+heapless = "0.7.13"
+
+[[example]]
+name = "demo"
+path = "../examples/demo.rs"
+required-features = ["alloc"]
+
+[[example]]
+name = "bar"
+path = "../examples/bar.rs"
+required-features = ["alloc"]
+
+[[example]]
+name = "button_click"
+path = "../examples/button_click.rs"
+required-features = ["alloc"]
+
+[[example]]
+name = "gauge"
+path = "../examples/gauge.rs"
+
+[[example]]
+name = "arc"
+path = "../examples/arc.rs"
+required-features = ["lvgl_alloc"]

lvgl/build.rs

@@ -0,0 +1,33 @@
+use lvgl_codegen::{CodeGen, Rusty};
+use proc_macro2::TokenStream;
+use quote::quote;
+use std::env;
+use std::fs::File;
+use std::io::prelude::*;
+use std::path::PathBuf;
+
+fn main() {
+    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
+    let rs = out_path.join("generated.rs");
+
+    let widgets_impl = lvgl_sys::_bindgen_raw_src();
+
+    let codegen = CodeGen::from(widgets_impl).unwrap();
+    let widgets_impl: Vec<TokenStream> = codegen
+        .get_widgets()
+        .iter()
+        .flat_map(|w| w.code(&()))
+        .collect();
+
+    let code = quote! {
+        #(#widgets_impl)*
+    };
+
+    let mut file = File::create(rs).unwrap();
+    writeln!(
+        file,
+        "/* automatically generated by lvgl-codegen */\n{}",
+        code
+    )
+    .unwrap();
+}

lvgl/src/allocator.rs

@@ -0,0 +1,20 @@
+use core::alloc::{GlobalAlloc, Layout};
+
+// Register the global allocator
+#[global_allocator]
+static ALLOCATOR: LvglAlloc = LvglAlloc;
+
+pub struct LvglAlloc;
+
+unsafe impl GlobalAlloc for LvglAlloc {
+    unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
+        // Make sure LVGL is initialized!
+        crate::lvgl_init();
+        lvgl_sys::lv_mem_alloc(layout.size() as lvgl_sys::size_t) as *mut u8
+    }
+
+    unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) {
+        crate::lvgl_init();
+        lvgl_sys::lv_mem_free(ptr as *const cty::c_void)
+    }
+}

lvgl/src/display.rs

@@ -1,124 +0,0 @@
-use crate::Color;
-use alloc::boxed::Box;
-use core::mem::MaybeUninit;
-use embedded_graphics;
-use embedded_graphics::prelude::*;
-use embedded_graphics::{drawable, DrawTarget};
-
-pub struct DisplayDriver {
-    pub(crate) raw: lvgl_sys::lv_disp_drv_t,
-}
-
-impl DisplayDriver {
-    // we should accept a Rc<RefCell<T>> and throw it in a box and add to the user_data of the callback handler function
-    pub fn new<T, C>(device: &mut T) -> Self
-    where
-        T: DrawTarget<C>,
-        C: PixelColor + From<Color>,
-    {
-        let disp_drv = unsafe {
-            // Create a display buffer for LittlevGL
-            let mut display_buffer =
-                Box::new(MaybeUninit::<lvgl_sys::lv_disp_buf_t>::uninit().assume_init());
-
-            // Declare a buffer for the refresh rate
-            const REFRESH_BUFFER_LEN: usize = 2;
-            let refresh_buffer1 = Box::new(
-                MaybeUninit::<
-                    [MaybeUninit<lvgl_sys::lv_color_t>;
-                        lvgl_sys::LV_HOR_RES_MAX as usize * REFRESH_BUFFER_LEN],
-                >::uninit()
-                .assume_init(),
-            );
-            let refresh_buffer2 = Box::new(
-                MaybeUninit::<
-                    [MaybeUninit<lvgl_sys::lv_color_t>;
-                        lvgl_sys::LV_HOR_RES_MAX as usize * REFRESH_BUFFER_LEN],
-                >::uninit()
-                .assume_init(),
-            );
-
-            // Initialize the display buffer
-            lvgl_sys::lv_disp_buf_init(
-                display_buffer.as_mut(),
-                Box::into_raw(refresh_buffer1) as *mut cty::c_void,
-                Box::into_raw(refresh_buffer2) as *mut cty::c_void,
-                lvgl_sys::LV_HOR_RES_MAX * REFRESH_BUFFER_LEN as u32,
-            );
-
-            // Descriptor of a display driver
-            let mut disp_drv = MaybeUninit::<lvgl_sys::lv_disp_drv_t>::uninit().assume_init();
-
-            // Basic initialization
-            lvgl_sys::lv_disp_drv_init(&mut disp_drv);
-
-            // Assign the buffer to the display
-            disp_drv.buffer = Box::into_raw(display_buffer);
-
-            // Set your driver function
-            disp_drv.flush_cb = Some(display_callback_wrapper::<T, C>);
-
-            // TODO: DrawHandler type here
-            disp_drv.user_data = device as *mut _ as *mut cty::c_void;
-
-            disp_drv
-        };
-        Self { raw: disp_drv }
-    }
-}
-
-// We need to keep a reference to the DisplayDriver in UI if we implement Drop
-// impl Drop for DisplayDriver {
-//     fn drop(&mut self) {
-//         // grab the user data and deref the DrawHandler to free the instance for dealloc in the Rust universe.
-//         unimplemented!()
-//     }
-// }
-
-// a reference is kept to the external drawing target (T)
-// the reference is kept in the callback function of the drawing handler
-// we need a reference counter for the drawing target and free the ref counter when the display is
-// destroyed.
-//type DrawHandler = Rc<RefCell<u8>>;
-//
-// impl Drop for DrawHandler {
-//     fn drop(&mut self) {
-//         unimplemented!()
-//     }
-// }
-
-unsafe extern "C" fn display_callback_wrapper<T, C>(
-    disp_drv: *mut lvgl_sys::lv_disp_drv_t,
-    area: *const lvgl_sys::lv_area_t,
-    color_p: *mut lvgl_sys::lv_color_t,
-) where
-    T: DrawTarget<C>,
-    C: PixelColor + From<Color>,
-{
-    // We need to make sure panics can't escape across the FFI boundary.
-    //let _ = std::panic::catch_unwind(|| {
-    let display_driver = *disp_drv;
-
-    // Rust code closure reference
-    let device = &mut *(display_driver.user_data as *mut T);
-
-    let ys = (*area).y1..=(*area).y2;
-    let xs = ((*area).x1..=(*area).x2).enumerate();
-    let x_len = ((*area).x2 - (*area).x1 + 1) as usize;
-    let pixels = ys
-        .enumerate()
-        .map(|(iy, y)| {
-            xs.clone().map(move |(ix, x)| {
-                let color_len = x_len * iy + ix;
-                let raw_color = Color::from_raw(*color_p.add(color_len));
-                drawable::Pixel(Point::new(x as i32, y as i32), raw_color.into())
-            })
-        })
-        .flatten();
-    // TODO: Maybe find a way to use `draw_image` method on the device instance.
-    let _ = device.draw_iter(pixels.into_iter());
-
-    // Indicate to LittlevGL that you are ready with the flushing
-    lvgl_sys::lv_disp_flush_ready(disp_drv);
-    //}); // end of panic::catch_unwind
-}

lvgl/src/global.rs

@@ -1,68 +0,0 @@
-use crate::{DisplayDriver, ObjectX};
-use alloc::boxed::Box;
-use core::marker::PhantomData;
-use core::ptr;
-use core::ptr::NonNull;
-use core::sync::atomic::{AtomicBool, Ordering};
-use core::time::Duration;
-
-// There can only be a single reference to LittlevGL library.
-static LVGL_IN_USE: AtomicBool = AtomicBool::new(false);
-
-#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug)]
-pub enum LvError {
-    Uninitialized,
-    AlreadyInUse,
-}
-
-pub struct UI {
-    // LittlevGL is not thread-safe by default.
-    _not_sync: PhantomData<*mut ()>,
-}
-
-// LittlevGL does not use thread locals.
-unsafe impl Send for UI {}
-
-impl UI {
-    pub fn init() -> Result<Self, LvError> {
-        if LVGL_IN_USE.compare_and_swap(false, true, Ordering::SeqCst) == false {
-            unsafe {
-                lvgl_sys::lv_init();
-            }
-            Ok(Self {
-                _not_sync: PhantomData,
-            })
-        } else {
-            Err(LvError::AlreadyInUse)
-        }
-    }
-
-    pub fn disp_drv_register(&mut self, display: DisplayDriver) {
-        // Throw display driver into a box and add to user data (if we need to get the display back)
-        // or simply forget the display pointer/object to prevent Drop to be called
-        // register it
-        unsafe {
-            let boxed = Box::new(display.raw);
-            lvgl_sys::lv_disp_drv_register(Box::into_raw(boxed));
-        }
-    }
-
-    pub fn scr_act(&self) -> ObjectX {
-        unsafe {
-            let screen = lvgl_sys::lv_disp_get_scr_act(ptr::null_mut());
-            ObjectX::from_raw(NonNull::new_unchecked(screen))
-        }
-    }
-
-    pub fn tick_inc(&mut self, tick_period: Duration) {
-        unsafe {
-            lvgl_sys::lv_tick_inc(tick_period.as_millis() as u32);
-        }
-    }
-
-    pub fn task_handler(&mut self) {
-        unsafe {
-            lvgl_sys::lv_task_handler();
-        }
-    }
-}

lvgl/src/lib.rs

@@ -1,12 +1,68 @@
-#![no_std]
+//! [![github]](https://github.com/rafaelcaricio/lvgl-rs) [![crates-io]](https://crates.io/crates/lvgl) [![docs-rs]](crate)
+//!
+//! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github
+//! [crates-io]: https://img.shields.io/badge/crates.io-fc8d62?style=for-the-badge&labelColor=555555&logo=rust
+//! [docs-rs]: https://img.shields.io/badge/docs.rs-66c2a5?style=for-the-badge&labelColor=555555&logoColor=white&logo=data:image/svg+xml;base64,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
+//!
+//! <br>
+//!
+//! [LVGL][1] bindings for Rust. A powerful and easy-to-use embedded GUI with many widgets, advanced visual effects, and
+//! low memory footprint. This crate is compatible with `#![no_std]` environments by default.
+//!
+//! [1]: https://docs.lvgl.io/v7/en/html/get-started/quick-overview.html
+//!
 
+#![cfg_attr(not(test), no_std)]
+
+#[macro_use]
+extern crate bitflags;
+
+#[cfg(feature = "lvgl_alloc")]
 extern crate alloc;
 
-mod global;
-mod display;
-mod support;
-mod widgets;
+// We can ONLY use `alloc::boxed::Box` if `lvgl_alloc` is enabled.
+// That is because we use `Box` to send memory references to LVGL. Since the global allocator, when
+// `lvgl_alloc` feature is enabled, is the LVGL memory manager then everything is in LVGL
+// managed memory anyways. In that case we can use the Rust's provided Box definition.
+//
+#[cfg(feature = "lvgl_alloc")]
+use ::alloc::boxed::Box;
 
-pub use global::{UI, LvError};
-pub use display::DisplayDriver;
+#[cfg(feature = "lvgl_alloc")]
+mod allocator;
+
+mod support;
+mod ui;
+#[macro_use]
+mod lv_core;
+pub mod widgets;
+
+#[cfg(not(feature = "lvgl_alloc"))]
+pub(crate) mod mem;
+
+// When LVGL allocator is not used on the Rust code, we need a way to add objects to the LVGL
+// managed memory. We implement a very simple `Box` that has the minimal features to copy memory
+// safely to the LVGL managed memory.
+//
+#[cfg(not(feature = "lvgl_alloc"))]
+use crate::mem::Box;
+
+pub use lv_core::*;
 pub use support::*;
+pub use ui::*;
+
+use core::sync::atomic::{AtomicBool, Ordering};
+
+// Initialize LVGL only once.
+static LVGL_INITIALIZED: AtomicBool = AtomicBool::new(false);
+
+pub(crate) fn lvgl_init() {
+    if LVGL_INITIALIZED
+        .compare_exchange(false, true, Ordering::Relaxed, Ordering::Relaxed)
+        .is_ok()
+    {
+        unsafe {
+            lvgl_sys::lv_init();
+        }
+    }
+}

lvgl/src/lv_core/mod.rs

@@ -0,0 +1,5 @@
+#[macro_use]
+mod obj;
+pub mod style;
+
+pub use obj::*;

lvgl/src/lv_core/obj.rs

@@ -0,0 +1,216 @@
+use crate::lv_core::style::Style;
+use crate::Box;
+use crate::{Align, LvError, LvResult};
+use core::ptr;
+
+/// Represents a native LVGL object
+pub trait NativeObject {
+    /// Provide common way to access to the underlying native object pointer.
+    fn raw(&self) -> LvResult<ptr::NonNull<lvgl_sys::lv_obj_t>>;
+}
+
+/// Generic LVGL object.
+///
+/// This is the parent object of all widget types. It stores the native LVGL raw pointer.
+pub struct Obj {
+    // We use a raw pointer here because we do not control this memory address, it is controlled
+    // by LVGL's global state.
+    raw: *mut lvgl_sys::lv_obj_t,
+}
+
+impl NativeObject for Obj {
+    fn raw(&self) -> LvResult<ptr::NonNull<lvgl_sys::lv_obj_t>> {
+        if let Some(non_null_ptr) = ptr::NonNull::new(self.raw) {
+            Ok(non_null_ptr)
+        } else {
+            Err(LvError::InvalidReference)
+        }
+    }
+}
+
+/// A wrapper for all LVGL common operations on generic objects.
+pub trait Widget: NativeObject {
+    type SpecialEvent;
+    type Part: Into<u8>;
+
+    /// Construct an instance of the object from a raw pointer.
+    ///
+    /// # Safety
+    /// Provided the LVGL library can allocate memory this should be safe.
+    ///
+    unsafe fn from_raw(raw_pointer: ptr::NonNull<lvgl_sys::lv_obj_t>) -> Self;
+
+    fn add_style(&self, part: Self::Part, style: Style) -> LvResult<()> {
+        unsafe {
+            lvgl_sys::lv_obj_add_style(self.raw()?.as_mut(), part.into(), Box::into_raw(style.raw));
+        };
+        Ok(())
+    }
+
+    fn set_pos(&mut self, x: i16, y: i16) -> LvResult<()> {
+        unsafe {
+            lvgl_sys::lv_obj_set_pos(
+                self.raw()?.as_mut(),
+                x as lvgl_sys::lv_coord_t,
+                y as lvgl_sys::lv_coord_t,
+            );
+        }
+        Ok(())
+    }
+
+    fn set_size(&mut self, w: i16, h: i16) -> LvResult<()> {
+        unsafe {
+            lvgl_sys::lv_obj_set_size(
+                self.raw()?.as_mut(),
+                w as lvgl_sys::lv_coord_t,
+                h as lvgl_sys::lv_coord_t,
+            );
+        }
+        Ok(())
+    }
+
+    fn set_width(&mut self, w: u32) -> LvResult<()> {
+        unsafe {
+            lvgl_sys::lv_obj_set_width(self.raw()?.as_mut(), w as lvgl_sys::lv_coord_t);
+        }
+        Ok(())
+    }
+
+    fn set_height(&mut self, h: u32) -> LvResult<()> {
+        unsafe {
+            lvgl_sys::lv_obj_set_height(self.raw()?.as_mut(), h as lvgl_sys::lv_coord_t);
+        }
+        Ok(())
+    }
+
+    fn set_align<C>(&mut self, base: &mut C, align: Align, x_mod: i32, y_mod: i32) -> LvResult<()>
+    where
+        C: NativeObject,
+    {
+        unsafe {
+            lvgl_sys::lv_obj_align(
+                self.raw()?.as_mut(),
+                base.raw()?.as_mut(),
+                align.into(),
+                x_mod as lvgl_sys::lv_coord_t,
+                y_mod as lvgl_sys::lv_coord_t,
+            );
+        }
+        Ok(())
+    }
+}
+
+impl Widget for Obj {
+    type SpecialEvent = ();
+    type Part = Part;
+
+    unsafe fn from_raw(raw: ptr::NonNull<lvgl_sys::lv_obj_t>) -> Self {
+        Self { raw: raw.as_ptr() }
+    }
+}
+
+impl Default for Obj {
+    fn default() -> Self {
+        Self {
+            raw: unsafe { lvgl_sys::lv_obj_create(ptr::null_mut(), ptr::null_mut()) },
+        }
+    }
+}
+
+macro_rules! define_object {
+    ($item:ident) => {
+        define_object!($item, event = (), part = $crate::Part);
+    };
+    ($item:ident, event = $event_type:ty) => {
+        define_object!($item, event = $event_type, part = $crate::Part);
+    };
+    ($item:ident, part = $part_type:ty) => {
+        define_object!($item, event = (), part = $part_type);
+    };
+    ($item:ident, part = $part_type:ty, event = $event_type:ty) => {
+        define_object!($item, event = $event_type, part = $part_type);
+    };
+    ($item:ident, event = $event_type:ty, part = $part_type:ty) => {
+        pub struct $item {
+            core: $crate::Obj,
+        }
+
+        unsafe impl Send for $item {}
+
+        impl $item {
+            pub fn on_event<F>(&mut self, f: F) -> $crate::LvResult<()>
+            where
+                F: FnMut(Self, $crate::support::Event<<Self as $crate::Widget>::SpecialEvent>),
+            {
+                use $crate::NativeObject;
+                unsafe {
+                    let mut raw = self.raw()?;
+                    let obj = raw.as_mut();
+                    let user_closure = $crate::Box::new(f);
+                    obj.user_data = $crate::Box::into_raw(user_closure) as *mut cty::c_void;
+                    lvgl_sys::lv_obj_set_event_cb(
+                        obj,
+                        lvgl_sys::lv_event_cb_t::Some($crate::support::event_callback::<Self, F>),
+                    );
+                }
+                Ok(())
+            }
+        }
+
+        impl $crate::NativeObject for $item {
+            fn raw(&self) -> $crate::LvResult<core::ptr::NonNull<lvgl_sys::lv_obj_t>> {
+                self.core.raw()
+            }
+        }
+
+        impl $crate::Widget for $item {
+            type SpecialEvent = $event_type;
+            type Part = $part_type;
+
+            unsafe fn from_raw(raw_pointer: core::ptr::NonNull<lvgl_sys::lv_obj_t>) -> Self {
+                Self {
+                    core: $crate::Obj::from_raw(raw_pointer),
+                }
+            }
+        }
+    };
+}
+
+bitflags! {
+    pub struct State: u32 {
+        /// Normal, released
+        const DEFAULT  = lvgl_sys::LV_STATE_DEFAULT as u32;
+        /// Toggled or checked
+        const CHECKED  = lvgl_sys::LV_STATE_CHECKED as u32;
+        /// Focused via keypad or encoder or clicked via touchpad/mouse
+        const FOCUSED  = lvgl_sys::LV_STATE_FOCUSED as u32;
+        /// Edit by an encoder
+        const EDITED   = lvgl_sys::LV_STATE_EDITED as u32;
+        /// Hovered by mouse (not supported now)
+        const HOVERED  = lvgl_sys::LV_STATE_HOVERED as u32;
+        /// Pressed
+        const PRESSED  = lvgl_sys::LV_STATE_PRESSED as u32;
+        /// Disabled or inactive
+        const DISABLED = lvgl_sys::LV_STATE_DISABLED as u32;
+    }
+}
+
+impl State {
+    pub(crate) fn get_bits(&self) -> u32 {
+        self.bits
+    }
+}
+
+pub enum Part {
+    Main,
+    All,
+}
+
+impl From<Part> for u8 {
+    fn from(self_: Part) -> u8 {
+        match self_ {
+            Part::Main => lvgl_sys::LV_OBJ_PART_MAIN as u8,
+            Part::All => lvgl_sys::LV_OBJ_PART_ALL as u8,
+        }
+    }
+}

lvgl/src/mem.rs

@@ -0,0 +1,174 @@
+use core::mem;
+use core::ops::{Deref, DerefMut};
+use core::ptr::NonNull;
+
+/// Places a sized `T` into LVGL memory.
+///
+/// This is useful for cases when we need to allocate memory on Rust side
+/// and handover the management of that memory to LVGL. May also be used in cases we
+/// want to use dynamic memory in the Rust side.
+pub(crate) struct Box<T>(NonNull<T>);
+
+impl<T> Box<T> {
+    /// Allocate memory using LVGL memory API and place `T` in the LVGL tracked memory.
+    pub fn new(value: T) -> Box<T> {
+        let size = mem::size_of::<T>();
+        let inner = unsafe {
+            let ptr = lvgl_sys::lv_mem_alloc(size as lvgl_sys::size_t) as *mut T;
+
+            // LVGL should align the memory address for us!
+            assert_eq!(
+                ptr as usize % mem::align_of::<T>(),
+                0,
+                "Memory address not aligned!"
+            );
+
+            NonNull::new(ptr)
+                .map(|p| {
+                    p.as_ptr().write(value);
+                    p
+                })
+                .unwrap_or_else(|| {
+                    panic!("Could not allocate memory {} bytes", size);
+                })
+        };
+        Box(inner)
+    }
+
+    pub fn into_raw(self) -> *mut T {
+        let b = mem::ManuallyDrop::new(self);
+        b.0.as_ptr()
+    }
+}
+
+impl<T> Drop for Box<T> {
+    fn drop(&mut self) {
+        unsafe {
+            lvgl_sys::lv_mem_free(self.0.as_ptr() as *const cty::c_void);
+        }
+    }
+}
+
+impl<T> DerefMut for Box<T> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        self.as_mut()
+    }
+}
+
+impl<T> Deref for Box<T> {
+    type Target = T;
+
+    fn deref(&self) -> &Self::Target {
+        unsafe { self.0.as_ref() }
+    }
+}
+
+impl<T> AsMut<T> for Box<T> {
+    fn as_mut(&mut self) -> &mut T {
+        unsafe { self.0.as_mut() }
+    }
+}
+
+impl<T: Clone> Clone for Box<T> {
+    fn clone(&self) -> Self {
+        unsafe { Self::new(self.0.as_ref().clone()) }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use std::vec::Vec;
+
+    #[test]
+    fn place_value_in_lv_mem() {
+        crate::lvgl_init();
+
+        let v = Box::new(5);
+        drop(v);
+        let v = Box::new(10);
+        drop(v);
+    }
+
+    #[test]
+    fn place_complex_value_in_lv_mem() {
+        crate::lvgl_init();
+
+        #[repr(C)]
+        #[derive(Debug)]
+        struct Point {
+            x: u64,
+            y: i8,
+            t: i32,
+            disp: i32,
+        }
+
+        let initial_mem_info = mem_info();
+
+        let mut keep = Vec::new();
+        for i in 0..100 {
+            let p = Point {
+                x: i,
+                y: 42,
+                t: 0,
+                disp: -100,
+            };
+
+            println!("{:?}", p);
+            let mut b = Box::new(p);
+
+            println!("memory address is {:p}", b.as_mut());
+
+            let point = b.as_mut();
+            if point.x != i {
+                println!("{:?}", point);
+            }
+            assert_eq!(point.x, i);
+
+            let info = mem_info();
+            println!("mem info: {:?}", &info);
+            keep.push(b);
+        }
+        drop(keep);
+
+        unsafe {
+            lvgl_sys::lv_mem_defrag();
+        }
+
+        let final_info = mem_info();
+        println!("mem info: {:?}", &final_info);
+
+        // If this fails, we are leaking memory! BOOM! \o/
+        assert_eq!(initial_mem_info.free_size, final_info.free_size)
+    }
+
+    #[test]
+    fn clone_object_in_lv_mem() {
+        crate::lvgl_init();
+
+        let v1 = Box::new(5);
+        let v2 = v1.clone();
+
+        // Ensure that the two objects have identical values.
+        assert_eq!(*v1, *v2);
+        // They should have different memory addresses, however.
+        assert_ne!(v1.into_raw() as usize, v2.into_raw() as usize);
+    }
+
+    fn mem_info() -> lvgl_sys::lv_mem_monitor_t {
+        let mut info = lvgl_sys::lv_mem_monitor_t {
+            total_size: 0,
+            free_cnt: 0,
+            free_size: 0,
+            free_biggest_size: 0,
+            used_cnt: 0,
+            max_used: 0,
+            used_pct: 0,
+            frag_pct: 0,
+        };
+        unsafe {
+            lvgl_sys::lv_mem_monitor(&mut info as *mut _);
+        }
+        info
+    }
+}

lvgl/src/support.rs

@@ -1,267 +1,21 @@
-use alloc::boxed::Box;
-use core::mem;
-use core::ptr;
-use cstr_core::CString;
+use crate::Widget;
+use core::convert::{TryFrom, TryInto};
+use core::ptr::NonNull;
 use embedded_graphics::pixelcolor::{Rgb565, Rgb888};
-use lvgl_sys;
 
-pub trait NativeObject {
-    fn raw(&self) -> ptr::NonNull<lvgl_sys::lv_obj_t>;
-}
+pub type LvResult<T> = Result<T, LvError>;
 
-pub struct ObjectX {
-    raw: ptr::NonNull<lvgl_sys::lv_obj_t>,
-}
-
-impl ObjectX {
-    pub(crate) fn from_raw(raw: ptr::NonNull<lvgl_sys::lv_obj_t>) -> Self {
-        Self { raw }
-    }
-}
-
-impl NativeObject for ObjectX {
-    fn raw(&self) -> ptr::NonNull<lvgl_sys::lv_obj_t> {
-        unsafe { ptr::NonNull::new_unchecked(self.raw.as_ptr()) }
-    }
-}
-
-pub trait Object: NativeObject {
-    fn set_pos(&mut self, x: i16, y: i16) {
-        unsafe {
-            lvgl_sys::lv_obj_set_pos(
-                self.raw().as_mut(),
-                x as lvgl_sys::lv_coord_t,
-                y as lvgl_sys::lv_coord_t,
-            );
-        }
-    }
-
-    fn set_size(&mut self, w: i16, h: i16) {
-        unsafe {
-            lvgl_sys::lv_obj_set_size(
-                self.raw().as_mut(),
-                w as lvgl_sys::lv_coord_t,
-                h as lvgl_sys::lv_coord_t,
-            );
-        }
-    }
-
-    fn set_width(&mut self, w: u32) {
-        unsafe {
-            lvgl_sys::lv_obj_set_width(self.raw().as_mut(), w as lvgl_sys::lv_coord_t);
-        }
-    }
-
-    fn set_height(&mut self, h: u32) {
-        unsafe {
-            lvgl_sys::lv_obj_set_height(self.raw().as_mut(), h as lvgl_sys::lv_coord_t);
-        }
-    }
-
-    fn set_align<C>(&mut self, base: &mut C, align: Align, x_mod: i32, y_mod: i32)
-    where
-        C: NativeObject,
-    {
-        let align = match align {
-            Align::Center => lvgl_sys::LV_ALIGN_CENTER,
-            Align::InTopLeft => lvgl_sys::LV_ALIGN_IN_TOP_LEFT,
-            Align::InTopMid => lvgl_sys::LV_ALIGN_IN_TOP_MID,
-            Align::InTopRight => lvgl_sys::LV_ALIGN_IN_TOP_RIGHT,
-            Align::InBottomLeft => lvgl_sys::LV_ALIGN_IN_BOTTOM_LEFT,
-            Align::InBottomMid => lvgl_sys::LV_ALIGN_IN_BOTTOM_MID,
-            Align::InBottomRight => lvgl_sys::LV_ALIGN_IN_BOTTOM_RIGHT,
-            Align::InLeftMid => lvgl_sys::LV_ALIGN_IN_LEFT_MID,
-            Align::InRightMid => lvgl_sys::LV_ALIGN_IN_RIGHT_MID,
-            Align::OutTopLeft => lvgl_sys::LV_ALIGN_OUT_TOP_LEFT,
-            Align::OutTopMid => lvgl_sys::LV_ALIGN_OUT_TOP_MID,
-            Align::OutTopRight => lvgl_sys::LV_ALIGN_OUT_TOP_RIGHT,
-            Align::OutBottomLeft => lvgl_sys::LV_ALIGN_OUT_BOTTOM_LEFT,
-            Align::OutBottomMid => lvgl_sys::LV_ALIGN_OUT_BOTTOM_MID,
-            Align::OutBottomRight => lvgl_sys::LV_ALIGN_OUT_BOTTOM_RIGHT,
-            Align::OutLeftTop => lvgl_sys::LV_ALIGN_OUT_LEFT_TOP,
-            Align::OutLeftMid => lvgl_sys::LV_ALIGN_OUT_LEFT_MID,
-            Align::OutLeftBottom => lvgl_sys::LV_ALIGN_OUT_LEFT_BOTTOM,
-            Align::OutRightTop => lvgl_sys::LV_ALIGN_OUT_RIGHT_TOP,
-            Align::OutRightMid => lvgl_sys::LV_ALIGN_OUT_RIGHT_MID,
-            Align::OutRightBottom => lvgl_sys::LV_ALIGN_OUT_RIGHT_BOTTOM,
-        } as lvgl_sys::lv_align_t;
-        unsafe {
-            lvgl_sys::lv_obj_align(
-                self.raw().as_mut(),
-                base.raw().as_mut(),
-                align,
-                x_mod as lvgl_sys::lv_coord_t,
-                y_mod as lvgl_sys::lv_coord_t,
-            );
-        }
-    }
-
-    fn set_style(&mut self, style: Style);
-}
-
-impl Object for ObjectX {
-    fn set_style(&mut self, style: Style) {
-        unsafe {
-            let boxed = Box::new(style.raw);
-            lvgl_sys::lv_obj_set_style(self.raw().as_mut(), Box::into_raw(boxed));
-        };
-    }
-}
-
-macro_rules! define_object {
-    ($item:ident) => {
-        pub struct $item {
-            core: ObjectX,
-        }
-
-        impl NativeObject for $item {
-            fn raw(&self) -> ptr::NonNull<lvgl_sys::lv_obj_t> {
-                self.core.raw()
-            }
-        }
-
-        impl Object for $item {
-            fn set_style(&mut self, style: Style) {
-                unsafe {
-                    let boxed = Box::new(style.raw);
-                    lvgl_sys::lv_obj_set_style(self.raw().as_mut(), Box::into_raw(boxed));
-                };
-            }
-        }
-    };
-}
-
-define_object!(Button);
-
-impl Button {
-    pub fn new<C>(parent: &mut C) -> Self
-    where
-        C: NativeObject,
-    {
-        let raw = unsafe {
-            let ptr = lvgl_sys::lv_btn_create(parent.raw().as_mut(), ptr::null_mut());
-            ptr::NonNull::new_unchecked(ptr)
-        };
-        let core = ObjectX::from_raw(raw);
-        Self { core }
-    }
-}
-
-pub enum LabelAlign {
-    Left,
-    Center,
-    Right,
-    Auto,
-}
-
-define_object!(Label);
-
-impl Label {
-    pub fn new<C>(parent: &mut C) -> Self
-    where
-        C: NativeObject,
-    {
-        let raw = unsafe {
-            let ptr = lvgl_sys::lv_label_create(parent.raw().as_mut(), ptr::null_mut());
-            ptr::NonNull::new_unchecked(ptr)
-        };
-        let core = ObjectX::from_raw(raw);
-        Self { core }
-    }
-
-    pub fn set_text(&mut self, text: &str) {
-        let text = CString::new(text).unwrap();
-        unsafe {
-            lvgl_sys::lv_label_set_text(self.core.raw().as_mut(), text.as_ptr());
-        }
-    }
-
-    pub fn set_label_align(&mut self, align: LabelAlign) {
-        let align = match align {
-            LabelAlign::Left => lvgl_sys::LV_LABEL_ALIGN_LEFT,
-            LabelAlign::Center => lvgl_sys::LV_LABEL_ALIGN_CENTER,
-            LabelAlign::Right => lvgl_sys::LV_LABEL_ALIGN_RIGHT,
-            LabelAlign::Auto => lvgl_sys::LV_LABEL_ALIGN_AUTO,
-        } as lvgl_sys::lv_label_align_t;
-        unsafe {
-            lvgl_sys::lv_label_set_align(self.core.raw().as_mut(), align);
-        }
-    }
-
-    pub fn set_recolor(&mut self, recolor: bool) {
-        unsafe {
-            lvgl_sys::lv_label_set_recolor(self.core.raw().as_mut(), recolor);
-        }
-    }
-}
-
-pub enum Themes {
-    Pretty,
-}
-
-pub struct Style {
-    raw: lvgl_sys::lv_style_t,
-}
-
-impl Style {
-    pub fn new() -> Self {
-        let raw = unsafe {
-            let mut native_style = mem::MaybeUninit::<lvgl_sys::lv_style_t>::uninit();
-            lvgl_sys::lv_style_copy(native_style.as_mut_ptr(), &lvgl_sys::lv_style_pretty);
-            native_style.assume_init()
-        };
-        Self { raw }
-    }
-
-    /// Object's main background color.
-    pub fn set_body_main_color(&mut self, color: Color) {
-        self.raw.body.main_color = color.raw;
-    }
-
-    /// Second color. If not equal to `set_body_main_color` a gradient will be drawn for the background.
-    pub fn set_body_grad_color(&mut self, color: Color) {
-        self.raw.body.grad_color = color.raw;
-    }
-
-    /// Text color.
-    pub fn set_text_color(&mut self, color: Color) {
-        self.raw.text.color = color.raw;
-    }
-
-    /// Font used for displaying the text.
-    pub fn set_text_font(&mut self, font: &lvgl_sys::lv_font_t) {
-        self.raw.text.font = font;
-    }
-
-    /// Body radius for rounded corners.
-    pub fn set_body_radius(&mut self, radius: i16) {
-        self.raw.body.radius = radius;
-    }
-
-    /// Border color.
-    pub fn set_body_border_color(&mut self, color: Color) {
-        self.raw.body.border.color = color.raw;
-    }
-}
-
-impl Clone for Style {
-    fn clone(&self) -> Self {
-        let mut native_style = mem::MaybeUninit::<lvgl_sys::lv_style_t>::uninit();
-        unsafe {
-            lvgl_sys::lv_style_copy(
-                native_style.as_mut_ptr(),
-                &self.raw as *const lvgl_sys::lv_style_t,
-            );
-            Self {
-                raw: native_style.assume_init(),
-            }
-        }
-    }
+#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug)]
+pub enum LvError {
+    InvalidReference,
+    Uninitialized,
+    LvOOMemory,
+    AlreadyInUse,
 }
 
 #[derive(Clone)]
 pub struct Color {
-    raw: lvgl_sys::lv_color_t,
+    pub(crate) raw: lvgl_sys::lv_color_t,
 }
 
 impl Color {
@@ -273,6 +27,18 @@ impl Color {
     pub fn from_raw(raw: lvgl_sys::lv_color_t) -> Self {
         Self { raw }
     }
+
+    pub fn r(&self) -> u8 {
+        unsafe { lvgl_sys::_LV_COLOR_GET_R(self.raw) as u8 }
+    }
+
+    pub fn g(&self) -> u8 {
+        unsafe { lvgl_sys::_LV_COLOR_GET_G(self.raw) as u8 }
+    }
+
+    pub fn b(&self) -> u8 {
+        unsafe { lvgl_sys::_LV_COLOR_GET_B(self.raw) as u8 }
+    }
 }
 
 impl From<Color> for Rgb888 {
@@ -299,6 +65,120 @@ impl From<Color> for Rgb565 {
     }
 }
 
+/// Events are triggered in LVGL when something happens which might be interesting to
+/// the user, e.g. if an object:
+///  - is clicked
+///  - is dragged
+///  - its value has changed, etc.
+///
+/// All objects (such as Buttons/Labels/Sliders etc.) receive these generic events
+/// regardless of their type.
+pub enum Event<T> {
+    /// The object has been pressed
+    Pressed,
+
+    /// The object is being pressed (sent continuously while pressing)
+    Pressing,
+
+    /// The input device is still being pressed but is no longer on the object
+    PressLost,
+
+    /// Released before `long_press_time` config time. Not called if dragged.
+    ShortClicked,
+
+    /// Called on release if not dragged (regardless to long press)
+    Clicked,
+
+    /// Pressing for `long_press_time` config time. Not called if dragged.
+    LongPressed,
+
+    /// Called after `long_press_time` config in every `long_press_rep_time` ms. Not
+    /// called if dragged.
+    LongPressedRepeat,
+
+    /// Called in every case when the object has been released even if it was dragged. Not called
+    /// if slid from the object while pressing and released outside of the object. In this
+    /// case, `Event<_>::PressLost` is sent.
+    Released,
+
+    /// Pointer-like input devices events (E.g. mouse or touchpad)
+    Pointer(PointerEvent),
+
+    /// Special event for the object type
+    Special(T),
+}
+
+impl<S> TryFrom<lvgl_sys::lv_event_t> for Event<S> {
+    type Error = ();
+
+    fn try_from(value: u8) -> Result<Self, Self::Error> {
+        const LV_EVENT_PRESSED: u32 = lvgl_sys::LV_EVENT_PRESSED as u32;
+        const LV_EVENT_PRESSING: u32 = lvgl_sys::LV_EVENT_PRESSING as u32;
+        const LV_EVENT_PRESS_LOST: u32 = lvgl_sys::LV_EVENT_PRESS_LOST as u32;
+        const LV_EVENT_SHORT_CLICKED: u32 = lvgl_sys::LV_EVENT_SHORT_CLICKED as u32;
+        const LV_EVENT_CLICKED: u32 = lvgl_sys::LV_EVENT_CLICKED as u32;
+        const LV_EVENT_LONG_PRESSED: u32 = lvgl_sys::LV_EVENT_LONG_PRESSED as u32;
+        const LV_EVENT_LONG_PRESSED_REPEAT: u32 = lvgl_sys::LV_EVENT_LONG_PRESSED_REPEAT as u32;
+        const LV_EVENT_RELEASED: u32 = lvgl_sys::LV_EVENT_RELEASED as u32;
+
+        match value as u32 {
+            LV_EVENT_PRESSED => Ok(Event::Pressed),
+            LV_EVENT_PRESSING => Ok(Event::Pressing),
+            LV_EVENT_PRESS_LOST => Ok(Event::PressLost),
+            LV_EVENT_SHORT_CLICKED => Ok(Event::ShortClicked),
+            LV_EVENT_CLICKED => Ok(Event::Clicked),
+            LV_EVENT_LONG_PRESSED => Ok(Event::LongPressed),
+            LV_EVENT_LONG_PRESSED_REPEAT => Ok(Event::LongPressedRepeat),
+            LV_EVENT_RELEASED => Ok(Event::Released),
+            _ => Err(()),
+        }
+    }
+}
+
+impl<S> From<Event<S>> for lvgl_sys::lv_event_t {
+    fn from(event: Event<S>) -> Self {
+        let native_event = match event {
+            Event::Pressed => lvgl_sys::LV_EVENT_PRESSED,
+            Event::Pressing => lvgl_sys::LV_EVENT_PRESSING,
+            Event::PressLost => lvgl_sys::LV_EVENT_PRESS_LOST,
+            Event::ShortClicked => lvgl_sys::LV_EVENT_SHORT_CLICKED,
+            Event::Clicked => lvgl_sys::LV_EVENT_CLICKED,
+            Event::LongPressed => lvgl_sys::LV_EVENT_LONG_PRESSED,
+            Event::LongPressedRepeat => lvgl_sys::LV_EVENT_LONG_PRESSED_REPEAT,
+            Event::Released => lvgl_sys::LV_EVENT_RELEASED,
+            // TODO: handle all types...
+            _ => lvgl_sys::LV_EVENT_CLICKED,
+        };
+        native_event as lvgl_sys::lv_event_t
+    }
+}
+
+/// These events are sent only by pointer-like input devices (E.g. mouse or touchpad)
+pub enum PointerEvent {
+    DragBegin,
+    DragEnd,
+    DragThrowBegin,
+}
+
+pub(crate) unsafe extern "C" fn event_callback<T, F>(
+    obj: *mut lvgl_sys::lv_obj_t,
+    event: lvgl_sys::lv_event_t,
+) where
+    T: Widget + Sized,
+    F: FnMut(T, Event<T::SpecialEvent>),
+{
+    // convert the lv_event_t to lvgl-rs Event type
+    if let Ok(event) = event.try_into() {
+        if let Some(obj_ptr) = NonNull::new(obj) {
+            let object = T::from_raw(obj_ptr);
+            // get the pointer from the Rust callback closure FnMut provided by users
+            let user_closure = &mut *((*obj).user_data as *mut F);
+            // call user callback closure
+            user_closure(object, event);
+        }
+    }
+}
+
 pub enum Align {
     Center,
     InTopLeft,
@@ -322,3 +202,66 @@ pub enum Align {
     OutRightMid,
     OutRightBottom,
 }
+
+impl From<Align> for u8 {
+    fn from(self_: Align) -> u8 {
+        let native = match self_ {
+            Align::Center => lvgl_sys::LV_ALIGN_CENTER,
+            Align::InTopLeft => lvgl_sys::LV_ALIGN_IN_TOP_LEFT,
+            Align::InTopMid => lvgl_sys::LV_ALIGN_IN_TOP_MID,
+            Align::InTopRight => lvgl_sys::LV_ALIGN_IN_TOP_RIGHT,
+            Align::InBottomLeft => lvgl_sys::LV_ALIGN_IN_BOTTOM_LEFT,
+            Align::InBottomMid => lvgl_sys::LV_ALIGN_IN_BOTTOM_MID,
+            Align::InBottomRight => lvgl_sys::LV_ALIGN_IN_BOTTOM_RIGHT,
+            Align::InLeftMid => lvgl_sys::LV_ALIGN_IN_LEFT_MID,
+            Align::InRightMid => lvgl_sys::LV_ALIGN_IN_RIGHT_MID,
+            Align::OutTopLeft => lvgl_sys::LV_ALIGN_OUT_TOP_LEFT,
+            Align::OutTopMid => lvgl_sys::LV_ALIGN_OUT_TOP_MID,
+            Align::OutTopRight => lvgl_sys::LV_ALIGN_OUT_TOP_RIGHT,
+            Align::OutBottomLeft => lvgl_sys::LV_ALIGN_OUT_BOTTOM_LEFT,
+            Align::OutBottomMid => lvgl_sys::LV_ALIGN_OUT_BOTTOM_MID,
+            Align::OutBottomRight => lvgl_sys::LV_ALIGN_OUT_BOTTOM_RIGHT,
+            Align::OutLeftTop => lvgl_sys::LV_ALIGN_OUT_LEFT_TOP,
+            Align::OutLeftMid => lvgl_sys::LV_ALIGN_OUT_LEFT_MID,
+            Align::OutLeftBottom => lvgl_sys::LV_ALIGN_OUT_LEFT_BOTTOM,
+            Align::OutRightTop => lvgl_sys::LV_ALIGN_OUT_RIGHT_TOP,
+            Align::OutRightMid => lvgl_sys::LV_ALIGN_OUT_RIGHT_MID,
+            Align::OutRightBottom => lvgl_sys::LV_ALIGN_OUT_RIGHT_BOTTOM,
+        };
+        native as u8
+    }
+}
+
+pub enum Animation {
+    ON,
+    OFF,
+}
+
+impl From<Animation> for lvgl_sys::lv_anim_enable_t {
+    fn from(anim: Animation) -> Self {
+        match anim {
+            Animation::ON => lvgl_sys::LV_ANIM_ON as u8,
+            Animation::OFF => lvgl_sys::LV_ANIM_OFF as u8,
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn color_properties_accessible() {
+        let color = Color::from_rgb((206, 51, 255));
+
+        if lvgl_sys::LV_COLOR_DEPTH == 32 {
+            assert_eq!(color.r(), 206);
+            assert_eq!(color.g(), 51);
+            assert_eq!(color.b(), 255);
+        } else if lvgl_sys::LV_COLOR_DEPTH == 16 {
+            assert_eq!(color.r(), 25);
+            assert_eq!(color.g(), 12);
+            assert_eq!(color.b(), 31);
+        }
+    }
+}

lvgl/src/ui.rs

@@ -0,0 +1,200 @@
+use crate::Box;
+use crate::{Color, Event, LvError, LvResult, Obj, Widget};
+use core::marker::PhantomData;
+use core::mem::MaybeUninit;
+use core::ptr;
+use core::ptr::NonNull;
+use core::sync::atomic::{AtomicBool, Ordering};
+use core::time::Duration;
+use embedded_graphics::draw_target::DrawTarget;
+use embedded_graphics::prelude::*;
+use embedded_graphics::{pixelcolor::PixelColor, Pixel};
+
+// There can only be a single reference to LVGL library.
+static LVGL_IN_USE: AtomicBool = AtomicBool::new(false);
+
+// TODO: Make this an external configuration
+const REFRESH_BUFFER_LEN: usize = 2;
+// Declare a buffer for the refresh rate
+pub(crate) const BUF_SIZE: usize = lvgl_sys::LV_HOR_RES_MAX as usize * REFRESH_BUFFER_LEN;
+
+pub struct UI<T, C>
+where
+    T: DrawTarget<Color = C>,
+    C: PixelColor + From<Color>,
+{
+    // LVGL is not thread-safe by default.
+    _not_sync: PhantomData<*mut ()>,
+    // Later we can add possibility to have multiple displays by using `heapless::Vec`
+    display_data: Option<DisplayUserData<T, C>>,
+}
+
+// LVGL does not use thread locals.
+unsafe impl<T, C> Send for UI<T, C>
+where
+    T: DrawTarget<Color = C>,
+    C: PixelColor + From<Color>,
+{
+}
+
+impl<T, C> UI<T, C>
+where
+    T: DrawTarget<Color = C>,
+    C: PixelColor + From<Color>,
+{
+    pub fn init() -> LvResult<Self> {
+        if LVGL_IN_USE
+            .compare_exchange(false, true, Ordering::Relaxed, Ordering::Relaxed)
+            .is_ok()
+        {
+            crate::lvgl_init();
+            Ok(Self {
+                _not_sync: PhantomData,
+                display_data: None,
+            })
+        } else {
+            Err(LvError::AlreadyInUse)
+        }
+    }
+
+    pub fn disp_drv_register(&mut self, display: T) -> LvResult<()> {
+        self.display_data = Some(DisplayUserData {
+            display,
+            phantom: PhantomData,
+        });
+
+        let refresh_buffer1 = [Color::from_rgb((0, 0, 0)).raw; BUF_SIZE];
+        let refresh_buffer2 = [Color::from_rgb((0, 0, 0)).raw; BUF_SIZE];
+
+        let mut disp_buf = MaybeUninit::<lvgl_sys::lv_disp_buf_t>::uninit();
+        let mut disp_drv = MaybeUninit::<lvgl_sys::lv_disp_drv_t>::uninit();
+
+        unsafe {
+            // Initialize the display buffer
+            lvgl_sys::lv_disp_buf_init(
+                disp_buf.as_mut_ptr(),
+                Box::into_raw(Box::new(refresh_buffer1)) as *mut cty::c_void,
+                Box::into_raw(Box::new(refresh_buffer2)) as *mut cty::c_void,
+                lvgl_sys::LV_HOR_RES_MAX * REFRESH_BUFFER_LEN as u32,
+            );
+            // Basic initialization of the display driver
+            lvgl_sys::lv_disp_drv_init(disp_drv.as_mut_ptr());
+            let mut disp_drv = Box::new(disp_drv.assume_init());
+            // Assign the buffer to the display
+            disp_drv.buffer = Box::into_raw(Box::new(disp_buf.assume_init()));
+            // Set your driver function
+            disp_drv.flush_cb = Some(display_callback_wrapper::<T, C>);
+            disp_drv.user_data = &mut self.display_data as *mut _ as *mut cty::c_void;
+            // We need to remember to deallocate the `disp_drv` memory when dropping UI
+            lvgl_sys::lv_disp_drv_register(Box::into_raw(disp_drv));
+        };
+
+        Ok(())
+    }
+
+    pub fn get_display_ref(&self) -> Option<&T> {
+        match self.display_data.as_ref() {
+            None => None,
+            Some(v) => Some(&v.display),
+        }
+    }
+
+    pub fn scr_act(&self) -> LvResult<Obj> {
+        unsafe {
+            let screen = lvgl_sys::lv_disp_get_scr_act(ptr::null_mut());
+            if let Some(v) = NonNull::new(screen) {
+                Ok(Obj::from_raw(v))
+            } else {
+                Err(LvError::InvalidReference)
+            }
+        }
+    }
+
+    pub fn event_send<W>(&mut self, obj: &mut W, event: Event<W::SpecialEvent>) -> LvResult<()>
+    where
+        W: Widget,
+    {
+        unsafe {
+            lvgl_sys::lv_event_send(obj.raw()?.as_mut(), event.into(), ptr::null_mut());
+        }
+        Ok(())
+    }
+
+    pub fn tick_inc(&mut self, tick_period: Duration) {
+        unsafe {
+            lvgl_sys::lv_tick_inc(tick_period.as_millis() as u32);
+        }
+    }
+
+    pub fn task_handler(&mut self) {
+        unsafe {
+            lvgl_sys::lv_task_handler();
+        }
+    }
+}
+
+pub(crate) struct DisplayUserData<T, C>
+where
+    T: DrawTarget<Color = C>,
+    C: PixelColor + From<Color>,
+{
+    display: T,
+    phantom: PhantomData<C>,
+}
+
+unsafe extern "C" fn display_callback_wrapper<T, C>(
+    disp_drv: *mut lvgl_sys::lv_disp_drv_t,
+    area: *const lvgl_sys::lv_area_t,
+    color_p: *mut lvgl_sys::lv_color_t,
+) where
+    T: DrawTarget<Color = C>,
+    C: PixelColor + From<Color>,
+{
+    // In the `std` world we would make sure to capture panics here and make them not escape across
+    // the FFI boundary. Since this library is focused on embedded platforms, we don't
+    // have an standard unwinding mechanism to rely upon.
+    let display_driver = *disp_drv;
+    // Rust code closure reference
+    if !display_driver.user_data.is_null() {
+        let user_data = &mut *(display_driver.user_data as *mut DisplayUserData<T, C>);
+        let x1 = (*area).x1;
+        let x2 = (*area).x2;
+        let y1 = (*area).y1;
+        let y2 = (*area).y2;
+        // TODO: Can we do anything when there is a error while flushing?
+        let _ = display_flush(&mut user_data.display, (x1, x2), (y1, y2), color_p);
+    }
+    // Indicate to LVGL that we are ready with the flushing
+    lvgl_sys::lv_disp_flush_ready(disp_drv);
+}
+
+// We separate this display flush function to reduce the amount of unsafe code we need to write.
+// This also provides a good separation of concerns, what is necessary from LVGL to work and
+// what is the lvgl-rs wrapper responsibility.
+fn display_flush<T, C>(
+    display: &mut T,
+    (x1, x2): (i16, i16),
+    (y1, y2): (i16, i16),
+    color_p: *mut lvgl_sys::lv_color_t,
+) -> Result<(), T::Error>
+where
+    T: DrawTarget<Color = C>,
+    C: PixelColor + From<Color>,
+{
+    let ys = y1..=y2;
+    let xs = (x1..=x2).enumerate();
+    let x_len = (x2 - x1 + 1) as usize;
+
+    // We use iterators here to ensure that the Rust compiler can apply all possible
+    // optimizations at compile time.
+    let pixels = ys.enumerate().flat_map(|(iy, y)| {
+        xs.clone().map(move |(ix, x)| {
+            let color_len = x_len * iy + ix;
+            let lv_color = unsafe { *color_p.add(color_len) };
+            let raw_color = Color::from_raw(lv_color);
+            Pixel(Point::new(x as i32, y as i32), raw_color.into())
+        })
+    });
+
+    display.draw_iter(pixels)
+}

lvgl/src/widgets/arc.rs

@@ -0,0 +1,56 @@
+use crate::widgets::Arc;
+
+impl Arc {
+    // /// Set the start angle, for the given arc part.
+    // /// 0 degrees for the right, 90 degrees for the bottom, etc.
+    // pub fn set_start_angle(&mut self, angle: u16, part: ArcPart) -> LvResult<()> {
+    //     match part {
+    //         ArcPart::Background => unsafe {
+    //             lvgl_sys::lv_arc_set_bg_start_angle(self.core.raw()?.as_mut(), angle)
+    //         },
+    //         ArcPart::Indicator => unsafe {
+    //             lvgl_sys::lv_arc_set_start_angle(self.core.raw()?.as_mut(), angle)
+    //         },
+    //     }
+    //     Ok(())
+    // }
+    //
+    // /// Set the end angle, for the given arc part.
+    // /// 0 degrees for the right, 90 degrees for the bottom, etc.
+    // pub fn set_end_angle(&self, angle: u16, part: ArcPart) -> LvResult<()> {
+    //     match part {
+    //         ArcPart::Background => unsafe {
+    //             lvgl_sys::lv_arc_set_bg_end_angle(self.core.raw()?.as_mut(), angle)
+    //         },
+    //         ArcPart::Indicator => unsafe {
+    //             lvgl_sys::lv_arc_set_end_angle(self.core.raw()?.as_mut(), angle)
+    //         },
+    //     }
+    //     Ok(())
+    // }
+    //
+    // /// Rotate the arc, `angle` degrees clockwise.
+    // pub fn set_rotation(&mut self, angle: u16) -> LvResult<()> {
+    //     unsafe {
+    //         lvgl_sys::lv_arc_set_rotation(self.core.raw()?.as_mut(), angle);
+    //     }
+    //     Ok(())
+    // }
+}
+
+/// The different parts, of an arc object.
+#[derive(Debug, Copy, Clone, PartialEq)]
+#[repr(u8)]
+pub enum ArcPart {
+    /// The background of the arc.
+    Background = lvgl_sys::LV_ARC_PART_BG as u8,
+    /// The indicator of the arc.
+    /// This is what moves/changes, depending on the arc's value.
+    Indicator = lvgl_sys::LV_ARC_PART_INDIC as u8,
+}
+
+impl From<ArcPart> for u8 {
+    fn from(part: ArcPart) -> Self {
+        part as u8
+    }
+}

lvgl/src/widgets/bar.rs

@@ -0,0 +1,39 @@
+use crate::support::Animation;
+use crate::widgets::Bar;
+use crate::{LvResult, NativeObject};
+
+impl Bar {
+    /// Set minimum and the maximum values of the bar
+    pub fn set_range(&mut self, min: i16, max: i16) -> LvResult<()> {
+        unsafe {
+            lvgl_sys::lv_bar_set_range(self.core.raw()?.as_mut(), min, max);
+        }
+        Ok(())
+    }
+
+    /// Set a new value on the bar
+    pub fn set_value(&mut self, value: i16, anim: Animation) -> LvResult<()> {
+        unsafe {
+            lvgl_sys::lv_bar_set_value(self.core.raw()?.as_mut(), value, anim.into());
+        }
+        Ok(())
+    }
+}
+
+/// The different parts, of a bar object.
+pub enum BarPart {
+    /// The background of the bar.
+    Background,
+    /// The indicator of the bar.
+    /// This is what moves/changes, depending on the bar's value.
+    Indicator,
+}
+
+impl From<BarPart> for u8 {
+    fn from(component: BarPart) -> Self {
+        match component {
+            BarPart::Background => lvgl_sys::LV_BAR_PART_BG as u8,
+            BarPart::Indicator => lvgl_sys::LV_BAR_PART_INDIC as u8,
+        }
+    }
+}

lvgl/src/widgets/gauge.rs

@@ -0,0 +1,15 @@
+pub enum GaugePart {
+    Main,
+    Major,
+    Needle,
+}
+
+impl From<GaugePart> for u8 {
+    fn from(part: GaugePart) -> Self {
+        match part {
+            GaugePart::Main => lvgl_sys::LV_GAUGE_PART_MAIN as u8,
+            GaugePart::Major => lvgl_sys::LV_GAUGE_PART_MAJOR as u8,
+            GaugePart::Needle => lvgl_sys::LV_GAUGE_PART_NEEDLE as u8,
+        }
+    }
+}

lvgl/src/widgets/label.rs

@@ -0,0 +1,20 @@
+use crate::widgets::Label;
+use crate::{LvResult, NativeObject};
+
+impl Label {
+    pub fn set_label_align(&mut self, align: LabelAlign) -> LvResult<()> {
+        unsafe {
+            lvgl_sys::lv_label_set_align(self.core.raw()?.as_mut(), align as u8);
+        }
+        Ok(())
+    }
+}
+
+#[derive(Debug, Copy, Clone, PartialEq)]
+#[repr(u8)]
+pub enum LabelAlign {
+    Left = lvgl_sys::LV_LABEL_ALIGN_LEFT as u8,
+    Center = lvgl_sys::LV_LABEL_ALIGN_CENTER as u8,
+    Right = lvgl_sys::LV_LABEL_ALIGN_RIGHT as u8,
+    Auto = lvgl_sys::LV_LABEL_ALIGN_AUTO as u8,
+}

lvgl/src/widgets/mod.rs

@@ -0,0 +1,12 @@
+mod arc;
+mod bar;
+mod gauge;
+mod label;
+
+include!(concat!(env!("OUT_DIR"), "/generated.rs"));
+
+use crate::NativeObject;
+pub use arc::*;
+pub use bar::*;
+pub use gauge::*;
+pub use label::*;