Example code doesn't compile


I tried to get the following code working on ESP32 and ILI9341 touch screen through Arudino IDE. I received error when I tried to compile.

What MCU/Processor/Board and compiler are you using?

ESP32 LILYGO and Arduino

What do you experience?

  1. I set #if to 1 in the lvgl-conf.h file.
  2. I tried to link lvgl.h by adding the filed address in the header, but that didn’t fix it either.
  3. I also tried to create the objects in the beginning of the code, that didn’t fix the issue either.
  4. I found all of the objects in the documentation and it is correctly written in the code, but for some reason the compiler can not access them. The simple Hello example compiles ok. I also run another simple example that creates two buttons and compiles ok.

What do you expect?

Code to reproduce

Add a code snippet to reproduce the issue in the simulator. It should contain only the relevant code which can be compiled. Bug reports without code snippets or with erroneous code snippets will not be reviewed.

Use the ```c and ``` tags to format your code:

#include <lvgl.h>
#include <Ticker.h>
#include <TFT_eSPI.h>
#include <lv_conf.h>


Ticker tick; /* timer for interrupt handler */
TFT_eSPI tft = TFT_eSPI(); /* TFT instance */
static lv_disp_buf_t disp_buf;
static lv_color_t buf[LV_HOR_RES_MAX * 10];

lv_obj_t * slider_label;
int screenWidth = 480;
int screenHeight = 320;

/* Display flushing */
void my_disp_flush(lv_disp_drv_t *disp, const lv_area_t *area, lv_color_t *color_p)
  uint16_t c;

  tft.startWrite(); /* Start new TFT transaction */
  tft.setAddrWindow(area->x1, area->y1, (area->x2 - area->x1 + 1), (area->y2 - area->y1 + 1)); /* set the working window */
  for (int y = area->y1; y <= area->y2; y++) {
    for (int x = area->x1; x <= area->x2; x++) {
      c = color_p->full;
      tft.writeColor(c, 1);
  tft.endWrite(); /* terminate TFT transaction */
  lv_disp_flush_ready(disp); /* tell lvgl that flushing is done */

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);

      return false;

    if(touchX>screenWidth || touchY > screenHeight)
      Serial.println("Y or y outside of expected parameters..");
      Serial.print(" x:");

      data->state = touched ? LV_INDEV_STATE_PR : LV_INDEV_STATE_REL; 
      /*Save the state and save the pressed coordinate*/
      //if(data->state == LV_INDEV_STATE_PR) touchpad_get_xy(&last_x, &last_y);
      /*Set the coordinates (if released use the last pressed coordinates)*/
      data->point.x = touchX;
      data->point.y = touchY;
      Serial.print("Data x");
      Serial.print("Data y");


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

/* Interrupt driven periodic handler */
static void lv_tick_handler(void)


void setup() {

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


  tft.begin(); /* TFT init */

  //uint16_t calData[5] = { 275, 3620, 264, 3532, 1 };
  uint16_t calData[5] = {299, 3588, 348, 3474, 1};

  lv_disp_buf_init(&disp_buf, buf, NULL, LV_HOR_RES_MAX * 10);

  /*Initialize the display*/
  lv_disp_drv_t disp_drv;
  disp_drv.hor_res = screenWidth;
  disp_drv.ver_res = screenHeight;
  disp_drv.flush_cb = my_disp_flush;
  disp_drv.buffer = &disp_buf;

  lv_indev_drv_t indev_drv;
  lv_indev_drv_init(&indev_drv);             /*Descriptor of a input device driver*/
  indev_drv.type = LV_INDEV_TYPE_POINTER;    /*Touch pad is a pointer-like device*/
  indev_drv.read_cb = my_touchpad_read;      /*Set your driver function*/
  lv_indev_drv_register(&indev_drv);         /*Finally register the driver*/

  /*Initialize the graphics library's tick*/
  tick.attach_ms(LVGL_TICK_PERIOD, lv_tick_handler);


void loop() {

  lv_task_handler(); /* let the GUI do its work */

static lv_obj_t *kb;

static void lv_main(){
  lv_obj_t * scr = lv_cont_create(NULL, NULL);

  lv_obj_t * tv = lv_tabview_create(scr, NULL);
  lv_obj_set_size(tv, lv_disp_get_hor_res(NULL), lv_disp_get_ver_res(NULL));
  lv_obj_t * tab1 = lv_tabview_add_tab(tv, "LIST TAB");
  lv_obj_t * tab2 = lv_tabview_add_tab(tv, "WRITE TAB");


static void create_tab1(lv_obj_t * parent){
  //List Tab
  lv_page_set_scrl_layout(parent, LV_LAYOUT_GRID);

static void create_tab2(lv_obj_t * parent){
  //Write Tab

  lv_obj_t * ta = lv_ta_create(parent, NULL);
  lv_obj_set_size(ta, lv_obj_get_width(parent) - 10, lv_obj_get_height(parent) / 2);
  lv_ta_set_cursor_type(ta, LV_CURSOR_BLOCK);
  lv_ta_set_text(ta, "hello!");

 /*Create a keyboard and apply the styles*/
  kb = lv_kb_create(parent, NULL);
  lv_obj_set_size(kb, lv_obj_get_width(parent) -10, lv_obj_get_height(parent) / 2 - 20);
  lv_obj_set_event_cb(kb, keyboard_event_cb);
  /*Assign the text area to the keyboard*/
  lv_kb_set_ta(kb, ta);

static void keyboard_event_cb(lv_obj_t * keyboard, lv_event_t event){
  lv_kb_def_event_cb(kb, event);
  if(event == LV_EVENT_APPLY){
  }else if(event == LV_EVENT_CANCEL){

and here is the compiler error:

C:\Users\XYZ\AppData\Local\Temp\arduino_modified_sketch_880399\sketch_sep10a.ino: In function 'void create_tab2(lv_obj_t*)':
sketch_sep10a:153:44: error: 'lv_ta_create' was not declared in this scope
   lv_obj_t * ta = lv_ta_create(parent, NULL);
sketch_sep10a:155:29: error: 'LV_CURSOR_BLOCK' was not declared in this scope
   lv_ta_set_cursor_type(ta, LV_CURSOR_BLOCK);
sketch_sep10a:155:44: error: 'lv_ta_set_cursor_type' was not declared in this scope
   lv_ta_set_cursor_type(ta, LV_CURSOR_BLOCK);
sketch_sep10a:156:30: error: 'lv_ta_set_text' was not declared in this scope
   lv_ta_set_text(ta, "hello!");
sketch_sep10a:159:33: error: 'lv_kb_create' was not declared in this scope
   kb = lv_kb_create(parent, NULL);
sketch_sep10a:163:22: error: 'lv_kb_set_ta' was not declared in this scope
   lv_kb_set_ta(kb, ta);
C:\Users\XYZ\AppData\Local\Temp\arduino_modified_sketch_880399\sketch_sep10a.ino: In function 'void keyboard_event_cb(lv_obj_t*, lv_event_t)':
sketch_sep10a:168:31: error: 'lv_kb_def_event_cb' was not declared in this scope
   lv_kb_def_event_cb(kb, event);
exit status 1
'lv_ta_create' was not declared in this scope

Screenshot and/or video

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Which version of LVGL are you using (check in lvgl.h)? If it’s 7.0+ lv_ta is now lv_textarea and lv_kb is now lv_keyboard.

Thank you that fixed the issue. I’m using the 7.0+ version.