Example doesn't compile in ESP32 with arduino IDE

How-to
1

I`m trying to test the library with and ESP32 node MCU and TFT LCD when I tried to upload the sketch I recive the next error:

/*LVGL_Arduino.ino: In function 'void setup()':
LVGL_Arduino:114:18: error: 'lv_ex_btn_1' was not declared in this scope
      lv_ex_btn_1();
                  ^
exit status 1
'lv_ex_btn_1' was not declared in this scope */

How can I make the example work?

/*#include <lvgl.h>
#include <TFT_eSPI.h>

TFT_eSPI tft = TFT_eSPI(); /* TFT instance */
static lv_disp_buf_t disp_buf;
static lv_color_t buf[LV_HOR_RES_MAX * 10];


int screenWidth = 240;
int screenHeight = 320;


#if USE_LV_LOG != 0
/* Serial debugging */
void my_print(lv_log_level_t level, const char * file, uint32_t line, const char * dsc)
{

    Serial.printf("%s@%d->%s\r\n", file, line, dsc);
    Serial.flush();
}
#endif

/* Display flushing */
void my_disp_flush(lv_disp_drv_t *disp, const lv_area_t *area, lv_color_t *color_p)
{
    uint32_t w = (area->x2 - area->x1 + 1);
    uint32_t h = (area->y2 - area->y1 + 1);

    tft.startWrite();
    tft.setAddrWindow(area->x1, area->y1, w, h);
    tft.pushColors(&color_p->full, w * h, true);
    tft.endWrite();

    lv_disp_flush_ready(disp);
}

/*Read the touchpad*/
bool my_touchpad_read(lv_indev_drv_t * indev_driver, lv_indev_data_t * data)
{
    uint16_t touchX, touchY;

    bool touched = tft.getTouch(&touchX, &touchY, 600);

    if(!touched)
    {
      data->state = LV_INDEV_STATE_REL;
      return false;
    }
    else
    {
      data->state = LV_INDEV_STATE_PR;
    }

    if(touchX>screenWidth || touchY > screenHeight)
    {
      Serial.println("Y or y outside of expected parameters..");
      Serial.print("y:");
      Serial.print(touchX);
      Serial.print(" x:");
      Serial.print(touchY);
    }
    else
    {
      /*Set the coordinates*/
      data->point.x = touchX;
      data->point.y = touchY;
  
      Serial.print("Data x");
      Serial.println(touchX);
      
      Serial.print("Data y");
      Serial.println(touchY);

    }

    return false; /*Return `false` because we are not buffering and no more data to read*/
}

void setup()
{
    Serial.begin(115200); /* prepare for possible serial debug */

    lv_init();

#if USE_LV_LOG != 0
    lv_log_register_print_cb(my_print); /* register print function for debugging */
#endif

    tft.begin(); /* TFT init */
    tft.setRotation(1); /* Landscape orientation */

    uint16_t calData[5] = { 275, 3620, 264, 3532, 1 };
    tft.setTouch(calData);
  
    lv_disp_buf_init(&disp_buf, buf, NULL, LV_HOR_RES_MAX * 10);

    /*Initialize the display*/
    lv_disp_drv_t disp_drv;
    lv_disp_drv_init(&disp_drv);
    disp_drv.hor_res = 320;
    disp_drv.ver_res = 240;
    disp_drv.flush_cb = my_disp_flush;
    disp_drv.buffer = &disp_buf;
    lv_disp_drv_register(&disp_drv);

    /*Initialize the (dummy) input device driver*/
    lv_indev_drv_t indev_drv;
    lv_indev_drv_init(&indev_drv);
    indev_drv.type = LV_INDEV_TYPE_POINTER;
    indev_drv.read_cb = my_touchpad_read;
    lv_indev_drv_register(&indev_drv);

   
     lv_ex_btn_1();
}


void loop()
{

    lv_task_handler(); /* let the GUI do its work */
    delay(5);
} */
2

I believe you need to include lv_examples/lv_examples.h as well.

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