LVGL - Light and Versatile Graphics Library

LVGL provides everything you need to create embedded GUI with easy-to-use graphical elements, beautiful visual effects and low memory footprint.

Website · Online demo · Docs · Forum ·

Features

Powerful building blocks: buttons, charts, lists, sliders, images, etc.
Advanced graphics: animations, anti-aliasing, opacity, smooth scrolling
Simultaneously use various input devices: touchscreen, mouse, keyboard, encoder, buttons, etc.
Simultaneously use multiple displays: e.g. monochrome and color display
Multi-language support with UTF-8 encoding, Bidirectional support, and Arabic text handling
Fully customizable graphical elements via CSS-like styles
Hardware independent to use with any microcontroller or display
Scalable to operate with little memory (64 kB Flash, 10 kB RAM)
OS, External memory and GPU are supported but not required
Single frame buffer operation even with advances graphical effects
Written in C for maximal compatibility (C++ compatible)
Micropython Binding exposes LVGL API in Micropython
Simulator to develop on PC without embedded hardware
Tutorials, examples, themes for rapid development
Documentation and API references

Supported devices

Basically, every modern controller (which is able to drive a display) is suitable to run LVGL. The minimal requirements are:

16, 32 or 64 bit microcontroller or processor
> 16 MHz clock speed is recommended
Flash/ROM: > 64 kB for the very essential components (> 180 kB is recommended)
RAM:
- Static RAM usage: ~2 kB depending on the used features and objects types
- Stack: > 2kB (> 8 kB is recommended)
- Dynamic data (heap): > 2 KB (> 16 kB is recommended if using several objects). Set by LV_MEM_SIZE in lv_conf.h.
- Display buffer: > "Horizontal resolution" pixels (> 10 × "Horizontal resolution" is recommended)
C99 or newer compiler

Note that the memory usage might vary depending on the architecture, compiler and build options.

Just to mention some platforms:

STM32F1, STM32F3, STM32F4, STM32F7, STM32L4
Microchip dsPIC33, PIC24, PIC32MX, PIC32MZ
NXP: Kinetis, LPC, iMX, iMX RT
Linux frame buffer (/dev/fb)
Raspberry PI
Espressif ESP32
Infineon aurix
Nordic NRF52
Quectell M66

Get started

his list shows the recommended way of learning the library:

Check the Online demos to see LVGL in action (3 minutes)
Read the Introduction page of the documentation (5 minutes)
Read the Quick overview page of the documentation (15 minutes)
Set up a Simulator (10 minutes)
Try out some Examples
Port LVGL to a board. See the Porting guide or check the ready to use Projects
Read the Overview page to get a better understanding of the library. (2-3 hours)
Check the documentation of the Widgets to see their features and usage
If you have questions got to the Forum
Read the Contributing guide to see how you can help to improve LVGL (15 minutes)

Examples

For more examples see the lv_examples repository.

Button with label

lv_obj_t * btn = lv_btn_create(lv_scr_act(), NULL);     /*Add a button the current screen*/
lv_obj_set_pos(btn, 10, 10);                            /*Set its position*/
lv_obj_set_size(btn, 100, 50);                          /*Set its size*/
lv_obj_set_event_cb(btn, btn_event_cb);                 /*Assign a callback to the button*/

lv_obj_t * label = lv_label_create(btn, NULL);          /*Add a label to the button*/
lv_label_set_text(label, "Button");                     /*Set the labels text*/

...

void btn_event_cb(lv_obj_t * btn, lv_event_t event)
{
    if(event == LV_EVENT_CLICKED) {
        printf("Clicked\n");
    }
}

LVGL from Micropython

Learn more about Micropython.

# Create a Button and a Label
scr = lv.obj()
btn = lv.btn(scr)
btn.align(lv.scr_act(), lv.ALIGN.CENTER, 0, 0)
label = lv.label(btn)
label.set_text("Button")

# Load the screen
lv.scr_load(scr)

Contributing

For a detailed description of contribution opportunities visit the Contributing section of the documentation.

b-xiang/lvgl