lvgl-rs/README.md
Rafael Caricio bcd771df47 Disable lvgl original comments in bindings
We disable the comments generation here because some comments
cause the `cargo test` command to fail. Some of the original
comments have invalid tokens like `TYPEDEFS` causing issues.
We should recommend users to look the original comments in the
original lvgl in their C API docs.
2021-03-06 21:50:39 +01:00

3.4 KiB

LittlevGL - Open-source Embedded GUI Library in Rust

Original LittlevGL demo image

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.

LittlevGL is compatible with #![no_std] environments by default.

Official LittlevGL Website · C library repository · Live demo


Rust bindings usage demo code.

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:

$ 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.

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:

$ DEP_LV_CONFIG_PATH=`pwd` cargo build

Building for embedded environments

We make use of bindgen for generating the bindings to LittlevGL at build time. There is a problem in cargo when building for no_std, so we need to use a workaround to build "lvgl-rs". The mainstrem issue in cargo is being tracked at rust-lang/cargo#7915.

$ DEP_LV_CONFIG_PATH=`pwd` cargo build -Zfeatures=build_dep

Running the demo

Hint for macOS users: Before you run the demos you need to make sure you have libsdl installed on your machine. To install it, use HomeBrew:

$ brew install sdl2

This project contains examples that can run in a desktop simulator.

First, make sure to pull lvgl-rs submodules:

$ git submodule init
$ git submodule update 

Then run the demo example:

$ DEP_LV_CONFIG_PATH=`pwd`/examples/include cargo run --example demo

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.

  • Displays: We use embedded_graphics library to draw to the display. You can use lvgl-rs with any of the embedded_graphics supported displays.
  • Events: You can listen and trigger events in widget objects.
  • 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.