Lightweight and User-Friendly GUI Solution for Embedded Systems – LameUI

// This example uses TFT_eSPI library on Arduino framework// Hardware: [MCU = ESP32, Display: ILI9341, Touch IC = XPT2046]
#include <TFT_eSPI.h> // Graphics and font library for ILI9341 driver chip
#include <SPI.h>// ... [ Include LameUI library and other required headers too] ...
#define HOR_RES    320#define VERT_RES  240#define DISP_BUFF_PX_CNT (HOR_RES * 10)
uint16_t disp_buffer[DISP_BUFF_PX_CNT];
TFT_eSPI tft = TFT_eSPI();  // Invoke library
uint8_t lui_memory[4000];
void draw_disp_buff_cb(uint16_t* disp_buff, lui_area_t* area);{
    tft.setAddrWindow(area->x, area->y, area->w, area->h);
    tft.pushColors(disp_buff, (area->w * area->h), 1);}
void read_touch_input_cb(lui_touch_input_data_t* inputdata){
    uint16_t x = 0, y = 0; // To store the touch coordinates
    // Pressed will be set true is there is a valid touch on the screen
    bool pressed = tft.getTouch(&x, &y);
    inputdata->is_pressed = pressed;
    if (pressed)    {
        inputdata->x = x;
        inputdata->y = y;
    }
    else    {
        inputdata->x = -1;
        inputdata->y = -1;
    }}
void setup(void) {
      // Initialize tft
    tft.init();
    tft.setTouch(touch_cal_data);
        // Initialize LameUI with some memory
    lui_init(lui_memory, sizeof(lui_memory));
        // Create a display driver object
    lui_dispdrv_t* display_driver = lui_dispdrv_create();
    lui_dispdrv_register(display_driver);
    lui_dispdrv_set_resolution(display_driver, HOR_RES, VERT_RES);
    lui_dispdrv_set_disp_buff(my_display_driver, disp_buffer, DISP_BUFF_PX_CNT);
  lui_dispdrv_set_draw_disp_buff_cb(my_display_driver, draw_disp_buff_cb);
        // Create touch input device
    lui_touch_input_dev_t* input_device = lui_touch_inputdev_create();
    lui_touch_inputdev_register(input_device);
    lui_touch_inputdev_set_read_input_cb(input_device, read_touch_input_cb);
    // ... [Add scene (mandatory) and other widgets] ...}
void loop(){    // Must update the UI periodically    lui_update();
    // ... [Do other stuffs] ...}

#include<stdio.h>#include "LameUI/lame_ui.h"//... other required includes ....
#define HOR_RES    320#define VERT_RES   240
// [Mandatory] Display buffer. Buffer pixel count must be multiple of Horizontal Resolution
#define DISP_BUFF_PX_CNT (HOR_RES * 10)uint16_t disp_buffer[DISP_BUFF_PX_CNT];
// [Mandatory] LameUI memory. Here we are giving it 2KB to work with.uint8_t lameui_memory[2000];
//----------- callback function prototypes ------------
void my_draw_disp_buff_cb (uint16_t* disp_buff, lui_area_t* area);
void my_input_read_cb (lui_touch_input_data_t *input);
void button_1_cb(lui_obj_t* button_obj);//-----------------------------------------------------
int main (){  // [Mandatory] At the starting, initialize LameUI with some working memory.    // This memory is used to create objects  lui_init(lameui_memory, sizeof(lameui_memory));
  //----------------------------------------------------------  //[Mandatory] creating display driver object  lui_dispdrv_t *my_display_driver = lui_dispdrv_create();  lui_dispdrv_register(my_display_driver);  lui_dispdrv_set_resolution(my_display_driver, HOR_RES, VERT_RES);  lui_dispdrv_set_disp_buff(my_display_driver, disp_buffer, DISP_BUFF_PX_CNT);  lui_dispdrv_set_draw_disp_buff_cb(my_display_driver, my_draw_disp_buff_cb);
    //[Optional] creating input device object  lui_touch_input_dev_t *my_input_device = lui_touch_inputdev_create();  lui_touch_inputdev_register(my_input_device);  lui_touch_inputdev_set_read_input_cb(my_input_device, my_input_read_cb);
  //----------------------------------------------------------  //[Mandatory] create and add a scene    // There must be at least one scene. It is at the top of the hierarchy. All     // other objects will be under the hierarchy of a scene. There can be multiple     // scenes. A particular object can be under only one scene at a time.  lui_obj_t* scene_1 = lui_scene_create();    // [Mandatory] A scene must be set as active scene. Only the active scene    // is rendered.  lui_scene_set_active(scene_1);
    // Create a label  lui_obj_t* label_1 = lui_label_create();    // [Mandatory] An object must have a parent which is either a `scene` or a     // descendent of `scene`.  lui_object_add_to_parent(label_1, scene_1);  lui_object_set_position(label_1, 5, 50);  lui_label_set_text(label_1, "This is Label 1. Below is Button 1");
  // Create a button  lui_obj_t* button_1 = lui_button_create();    // [Mandatory] Add a parent  lui_object_add_to_parent(button_1, scene_1);  lui_object_set_area(button_1, 110, 40);  lui_object_set_position(button_1, 65, 100);  lui_button_set_label_text(button_1, "Button 1");  lui_object_set_callback(button_1, button_1_cb);
  while (1)  {    // LameUI has no built-in timer. So, update LameUI periodically.    // lui_update() function reads inputs, checks if anything needs to be drawn, and fires callbacks if and when needed.    lui_update();    sleep_ms(15);  }
  return 0;}
//----------- callback function definitions  ------------
void my_draw_disp_buff_cb(uint16_t* disp_buff, lui_area_t* area);{  uint16_t x = area->x;  // start x  uint16_t y = area->y;  // start y  uint16_t w = area->w;  // width  uint16_t h = area->h;  // height    display_draw_buffer(disp_buff, x, y, w, h);}
void my_input_read_cb (lui_touch_input_data_t *input){  // Assuming that user has a function display_get_touch() that returns a `touch_data_t` variable.  // Also assuming that members of `touch_data_t` are: pressed(uint8_t), x(uint16_t), y(uint16_t).  touch_data_t touch = display_get_touch();
  input->is_pressed = touch.pressed;  // `touch.pressed` should be 1 if touched, 0 if not touched  if (input->is_pressed == 1)  {    input->y = touch.y;    input->x = touch.x;  }  else  {    // IMPORTANT: User MUST set x and y as -1 when display is NOT touched.    input->y = -1;    input->x = -1;  }}
void button_1_cb(lui_obj_t* button_obj){  // Get the event of callback  int8_t event = lui_object_get_event(button_obj);  if (event == -1)    return;    if (event == LUI_EVENT_PRESSED)  {    // Button is pressed. Do something    fprintf(stderr, "Button 1 is pressed");  }  else if (event == LUI_EVENT_RELEASED)  {    // Button is released. Do something    fprintf(stderr, "Button 1 is released");  }}