examples/arc.rs

@@ -4,12 +4,16 @@ use embedded_graphics::prelude::*;
 use embedded_graphics_simulator::{
     OutputSettingsBuilder, SimulatorDisplay, SimulatorEvent, Window,
 };
+use lvgl::display::Display;
 use lvgl::style::Style;
 use lvgl::widgets::{Arc, Label, LabelAlign};
-use lvgl::{self, Align, Color, Part, State, UI};
+use lvgl::{self, Align, Color, Part, State};
 use lvgl::{LvError, Widget};
 use lvgl_sys;
-use std::time::Instant;
+use parking_lot::Mutex;
+use std::sync::Arc as SyncArc;
+use std::thread;
+use std::time::{Duration, Instant};
 
 fn mem_info() -> lvgl_sys::lv_mem_monitor_t {
     let mut info = lvgl_sys::lv_mem_monitor_t {
@@ -36,7 +40,9 @@ fn main() -> Result<(), LvError> {
 }
 
 fn run_arc_demo() -> Result<(), LvError> {
-    let display: SimulatorDisplay<Rgb565> = SimulatorDisplay::new(Size::new(
+    lvgl::init();
+
+    let embedded_graphics_display: SimulatorDisplay<Rgb565> = SimulatorDisplay::new(Size::new(
         lvgl_sys::LV_HOR_RES_MAX,
         lvgl_sys::LV_VER_RES_MAX,
     ));
@@ -44,40 +50,45 @@ fn run_arc_demo() -> Result<(), LvError> {
     let output_settings = OutputSettingsBuilder::new().scale(2).build();
     let mut window = Window::new("Arc Example", &output_settings);
 
-    let mut ui = UI::init()?;
+    let shared_native_display = SyncArc::new(Mutex::new(embedded_graphics_display));
+    let display = Display::register_shared(&shared_native_display)?;
 
-    // Implement and register your display:
+    let mut screen = display.get_str_act()?;
-    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)?;
+    screen.add_style(Part::Main, &mut screen_style)?;
 
     // Create the arc object
-    let mut arc = Arc::new(&mut screen)?;
+    let mut arc = Arc::new()?;
     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)?;
+    let mut loading_lbl = Label::new()?;
     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)?;
+    loading_lbl.add_style(Part::Main, &mut loading_style)?;
 
     let mut angle = 0;
     let mut forward = true;
     let mut i = 0;
 
-    let mut loop_started = Instant::now();
+    // LVGL timer thread
+    thread::spawn(|| {
+        let interval = Duration::from_millis(5);
+        loop {
+            thread::sleep(interval);
+            lvgl::tick_inc(interval);
+        }
+    });
+
     'running: loop {
         if i > 270 {
             forward = if forward { false } else { true };
@@ -88,8 +99,11 @@ fn run_arc_demo() -> Result<(), LvError> {
         arc.set_end_angle(angle + 135)?;
         i += 1;
 
-        ui.task_handler();
+        lvgl::task_handler();
-        window.update(ui.get_display_ref().unwrap());
+        {
+            let eg_display = shared_native_display.lock();
+            window.update(&eg_display);
+        }
 
         for event in window.events() {
             match event {
@@ -97,9 +111,7 @@ fn run_arc_demo() -> Result<(), LvError> {
                 _ => {}
             }
         }
-
+        thread::sleep(Duration::from_millis(15));
-        ui.tick_inc(loop_started.elapsed());
-        loop_started = Instant::now();
     }
 
     Ok(())

examples/demo.rs

@@ -12,25 +12,24 @@ use lvgl::{Align, Color, LvError, Part, State, Widget, UI};
 use lvgl_sys;
 use parking_lot::Mutex;
 use std::sync::Arc as SyncArc;
+use std::thread;
 use std::thread::sleep;
 use std::time::{Duration, Instant};
 
 fn main() -> Result<(), LvError> {
+    lvgl::init();
+
     let embedded_graphics_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 output_settings = OutputSettingsBuilder::new().scale(1).build();
     let mut window = Window::new("PineTime", &output_settings);
 
-    lvgl::init();
-    // let mut ui = UI::init()?;
-
     // Implement and register your display:
     let shared_native_display = SyncArc::new(Mutex::new(embedded_graphics_display));
     let _display = Display::register_shared(&shared_native_display)?;
-    // ui.disp_drv_register(embedded_graphics_display).unwrap();
 
     // Create screen and widgets
     let mut screen = DefaultDisplay::get_scr_act()?;
@@ -40,52 +39,52 @@ fn main() -> Result<(), LvError> {
     screen_style.set_radius(State::DEFAULT, 0);
     screen.add_style(Part::Main, &mut screen_style)?;
 
-    let mut time = Label::new()?;
+    let mut time = Label::from("20:46");
     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, &mut 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()?;
+    let mut bt = Label::from("#5794f2 \u{F293}#");
     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()?;
+    let mut power: Label = "#fade2a 20%#".into();
     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)?;
 
+    // LVGL timer thread
+    thread::spawn(|| {
+        let interval = Duration::from_millis(5);
+        loop {
+            thread::sleep(interval);
+            lvgl::tick_inc(interval);
+        }
+    });
+
     let mut i = 0;
-    let mut loop_started = Instant::now();
     'running: loop {
         if i > 59 {
             i = 0;
         }
-        println!("i = {}", i);
         let val = CString::new(format!("21:{:02}", i)).unwrap();
         time.set_text(&val)?;
         i = 1 + i;
 
-        let wait_for = lvgl::task_handler();
+        lvgl::task_handler();
-        println!("wait for = {} ms", wait_for.unwrap().as_secs());
         {
             let native_display = shared_native_display.lock();
             window.update(&native_display);
         }
-        // ui.task_handler();
-        // window.update(ui.get_display_ref().unwrap());
-        lvgl::tick_inc(loop_started.elapsed());
 
         for event in window.events() {
             match event {
@@ -94,8 +93,6 @@ fn main() -> Result<(), LvError> {
             }
         }
         sleep(Duration::from_secs(1));
-
-        loop_started = Instant::now();
     }
 
     Ok(())

lvgl-codegen/src/analysis.rs

@@ -0,0 +1,25 @@
+/// A parameter of C functions.
+///
+/// This struct represents all relevant information we can extract from the C function declaration
+/// of a LVGL public interface. We can use this information to do inference for how the parameter
+/// should be represented in a safe Rust API.
+pub struct CParameter {
+    /// The name of the parameter in the C code.
+    name: String,
+
+    /// This is the raw representation of the Rust equivalent of the C type.
+    c_type: String,
+
+    /// Takes a pointer to a type that is referenced by the LVGL code permanently.
+    owned: bool,
+
+    /// The pointer is not marked as `*const` so the referenced object can be mutated.
+    mutable: bool,
+
+    /// We need to check if the value is optional in the C code. We need to check
+    /// the function comments for this information.
+    ///     - "if NULL then"
+    ///     - "if not NULL then"
+    ///     - "NULL to"
+    nullable: bool,
+}

lvgl-codegen/src/lib.rs

@@ -1,3 +1,5 @@
+mod analysis;
+
 use inflector::cases::pascalcase::to_pascal_case;
 use lazy_static::lazy_static;
 use proc_macro2::{Ident, TokenStream};
@@ -44,6 +46,12 @@ pub struct LvWidget {
     methods: Vec<LvFunc>,
 }
 
+impl LvWidget {
+    fn pascal_name(&self) -> String {
+        to_pascal_case(&self.name)
+    }
+}
+
 impl Rusty for LvWidget {
     type Parent = ();
 
@@ -53,7 +61,7 @@ impl Rusty for LvWidget {
             return Err(WrapperError::Skip);
         }
 
-        let widget_name = format_ident!("{}", to_pascal_case(self.name.as_str()));
+        let widget_name = format_ident!("{}", self.pascal_name());
         let methods: Vec<TokenStream> = self.methods.iter().flat_map(|m| m.code(self)).collect();
         Ok(quote! {
             define_object!(#widget_name);
@@ -90,6 +98,7 @@ impl Rusty for LvFunc {
     type Parent = LvWidget;
 
     fn code(&self, parent: &Self::Parent) -> WrapperResult<TokenStream> {
+        let widget_name = format_ident!("{}", parent.pascal_name());
         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);
@@ -99,12 +108,12 @@ impl Rusty for LvFunc {
         if new_name.as_str().eq("create") {
             return Ok(quote! {
 
-                pub fn new<C>(parent: &mut C) -> crate::LvResult<Self>
+                pub fn create(parent: &mut impl crate::NativeObject, copy: Option<&#widget_name>) -> crate::LvResult<Self> {
-                where
-                    C: crate::NativeObject,
-                {
                     unsafe {
-                        let ptr = lvgl_sys::#original_func_name(parent.raw()?.as_mut(), core::ptr::null_mut());
+                        let ptr = lvgl_sys::#original_func_name(
+                            parent.raw()?.as_mut(),
+                            copy.map(|c| c.raw().unwrap().as_mut() as *mut lvgl_sys::lv_obj_t).unwrap_or(core::ptr::null_mut() as *mut lvgl_sys::lv_obj_t),
+                        );
                         if let Some(raw) = core::ptr::NonNull::new(ptr) {
                             let core = <crate::Obj as crate::Widget>::from_raw(raw);
                             Ok(Self { core })
@@ -114,6 +123,15 @@ impl Rusty for LvFunc {
                     }
                 }
 
+                pub fn create_at(parent: &mut impl crate::NativeObject) -> crate::LvResult<Self> {
+                    Ok(Self::create(parent, None)?)
+                }
+
+                pub fn new() -> crate::LvResult<Self> {
+                    let mut parent = crate::display::DefaultDisplay::get_scr_act()?;
+                    Ok(Self::create_at(&mut parent)?)
+                }
+
             });
         }
 
@@ -338,6 +356,9 @@ impl Rusty for LvType {
             Some(name) => {
                 let val = if self.is_str() {
                     quote!(&cstr_core::CStr)
+                } else if (self.literal_name.contains("lv_")) {
+                    let ident = format_ident!("{}", name);
+                    quote!(&#ident)
                 } else {
                     let ident = format_ident!("{}", name);
                     quote!(#ident)
@@ -631,13 +652,12 @@ mod test {
             define_object!(Arc);
 
             impl Arc {
-                pub fn new<C>(parent: &mut C) -> crate::LvResult<Self>
+                pub fn create(parent: &mut impl crate::NativeObject, copy: Option<&Arc>) -> crate::LvResult<Self> {
-                where
-                    C: crate::NativeObject,
-                {
-
                     unsafe {
-                        let ptr = lvgl_sys::lv_arc_create(parent.raw()?.as_mut(), core::ptr::null_mut());
+                        let ptr = lvgl_sys::lv_arc_create(
+                            parent.raw()?.as_mut(),
+                            copy.map(|c| c.raw().unwrap().as_mut() as *mut lvgl_sys::lv_obj_t).unwrap_or(core::ptr::null_mut() as *mut lvgl_sys::lv_obj_t),
+                        );
                         if let Some(raw) = core::ptr::NonNull::new(ptr) {
                             let core = <crate::Obj as crate::Widget>::from_raw(raw);
                             Ok(Self { core })
@@ -646,6 +666,16 @@ mod test {
                         }
                     }
                 }
+
+                pub fn create_at(parent: &mut impl crate::NativeObject) -> crate::LvResult<Self> {
+                    Ok(Self::create(parent, None)?)
+                }
+
+                pub fn new() -> crate::LvResult<Self> {
+                    Ok(Self::create_at(
+                        &mut crate::display::DefaultDisplay::get_scr_act(),
+                    )?)
+                }
             }
         };
 

lvgl/src/display.rs

@@ -10,7 +10,7 @@ use embedded_graphics::drawable;
 use embedded_graphics::prelude::*;
 
 #[cfg(feature = "alloc")]
-use parking_lot::Mutex;
+use parking_lot::Mutex; // TODO: Can this really be used in no_std envs with alloc?
 
 #[cfg(feature = "alloc")]
 use alloc::sync::Arc;
@@ -90,14 +90,15 @@ impl DisplayBuffer {
     pub fn new() -> Self {
         let disp_buf = unsafe {
             let mut disp_buf = MaybeUninit::uninit();
+            // TODO: Need to find a way to not add this to LVGL memory.
             let mut refresh_buffer1 = Box::new([lvgl_sys::lv_color_t::default(); BUF_SIZE]);
-            let mut refresh_buffer2 = Box::new([lvgl_sys::lv_color_t::default(); BUF_SIZE]);
+            //let mut refresh_buffer2 = Box::new([lvgl_sys::lv_color_t::default(); BUF_SIZE]);
             // let refresh_buffer2 = [lvgl_sys::lv_color_t::default(); BUF_SIZE];
             lvgl_sys::lv_disp_buf_init(
                 disp_buf.as_mut_ptr(),
                 Box::into_raw(refresh_buffer1) as *mut cty::c_void,
-                Box::into_raw(refresh_buffer2) as *mut cty::c_void,
+                //  Box::into_raw(refresh_buffer2) as *mut cty::c_void,
-                //ptr::null_mut(),
+                ptr::null_mut(),
                 lvgl_sys::LV_HOR_RES_MAX * REFRESH_BUFFER_LEN as u32,
             );
             disp_buf.assume_init()

lvgl/src/functions.rs

@@ -42,6 +42,10 @@ pub(crate) fn get_str_act(disp: Option<&Display>) -> Result<Obj> {
     ))
 }
 
+/// You have to call this function periodically.
+/// Expects a `tick_period` duration as argument which is the call period of this
+/// function in milliseconds.
+#[inline]
 pub fn tick_inc(tick_period: Duration) {
     unsafe {
         lvgl_sys::lv_tick_inc(tick_period.as_millis() as u32);
@@ -49,8 +53,7 @@ pub fn tick_inc(tick_period: Duration) {
 }
 
 /// Call it periodically to handle tasks.
-/// Returns the duration after which it must be called again.
+#[inline]
-pub fn task_handler() -> Option<Duration> {
+pub fn task_handler() {
-    let next_call_at = unsafe { lvgl_sys::lv_task_handler() };
+    unsafe { lvgl_sys::lv_task_handler() };
-    Some(Duration::from_secs(next_call_at as u64))
 }

lvgl/src/lib.rs

@@ -23,7 +23,7 @@ extern crate lazy_static;
 #[macro_use]
 mod lv_core;
 
-#[cfg(feature = "lvgl_alloc")]
+#[cfg(feature = "alloc")]
 extern crate alloc;
 
 // We can ONLY use `alloc::boxed::Box` if `lvgl_alloc` is enabled.

lvgl/src/mem.rs

@@ -36,8 +36,8 @@ impl<T> Box<T> {
     }
 
     pub fn into_raw(self) -> *mut T {
-        let b = mem::ManuallyDrop::new(self.0);
+        let b = mem::ManuallyDrop::new(self);
-        b.as_ptr()
+        b.0.as_ptr()
     }
 }
 

lvgl/src/support.rs

@@ -1,3 +1,4 @@
+use crate::display::DisplayError;
 use crate::Widget;
 use core::convert::{TryFrom, TryInto};
 use core::ptr::NonNull;
@@ -13,6 +14,17 @@ pub enum LvError {
     AlreadyInUse,
 }
 
+impl From<DisplayError> for LvError {
+    fn from(err: DisplayError) -> Self {
+        use LvError::*;
+        match err {
+            DisplayError::NotAvailable => Uninitialized,
+            DisplayError::FailedToRegister => InvalidReference,
+            DisplayError::NotRegistered => Uninitialized,
+        }
+    }
+}
+
 #[derive(Clone)]
 pub struct Color {
     pub(crate) raw: lvgl_sys::lv_color_t,

lvgl/src/widgets/label.rs

@@ -1,6 +1,9 @@
 use crate::widgets::Label;
 use crate::{LvResult, NativeObject};
 
+#[cfg(feature = "alloc")]
+use cstr_core::CString;
+
 impl Label {
     pub fn set_label_align(&mut self, align: LabelAlign) -> LvResult<()> {
         unsafe {
@@ -10,6 +13,16 @@ impl Label {
     }
 }
 
+#[cfg(feature = "alloc")]
+impl<S: AsRef<str>> From<S> for Label {
+    fn from(text: S) -> Self {
+        let text_cstr = CString::new(text.as_ref()).unwrap();
+        let mut label = Label::new().unwrap();
+        label.set_text(text_cstr.as_c_str()).unwrap();
+        label
+    }
+}
+
 #[derive(Debug, Copy, Clone, PartialEq)]
 #[repr(u8)]
 pub enum LabelAlign {