lvgl-rs/README.md

LVGL - Open-source Embedded GUI Library in Rust

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.

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

Rust to WASM demo · Official LVGL Website · C library repository · Official live demos

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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 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:

$ 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

LVGL Global Allocator

A global allocator for Rust leveraging the LVGL memory allocator 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

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 --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.

• 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.