File content as of revision 3:4f5dc253eb7b:

//Notebook page https://os.mbed.com/users/JohnnyK/notebook/how-start-with-the-littlevgl/
#include "mbed.h"
#include "lvgl/lvgl.h"
#include "hal_stm_lvgl/tft/tft.h"
#include "hal_stm_lvgl/touchpad/touchpad.h" 
#include "lv_examples.h"    /*Comment/uncomment will switch between LVGL demo and Hello word example*/

#define LVGL_TICK   10                               //Time tick value for lvgl in ms (1-10msa)
#define TICKER_TIME 10ms                             //modified to miliseconds

Ticker ticker;                                       //Ticker for lvgl                    
 
//Callback function for lvgl timing.
void lv_ticker_func(){
    lv_tick_inc(LVGL_TICK); 
    //Call lv_tick_inc(x) every x milliseconds in a Timer or Task (x should be between 1 and 10). 
    //It is required for the internal timing of LittlevGL.
}

#ifndef LV_EXAMPLES_H
static void event_handler(lv_obj_t * obj, lv_event_t event)
{
    if(event == LV_EVENT_CLICKED) {
        printf("Clicked\n");
    }
    else if(event == LV_EVENT_VALUE_CHANGED) {
        printf("Toggled\n");
    }
}
#endif
// main() runs in its own thread in the OS
int main()
{
    printf("LVGL-"); 
    lv_init();                                              //Initialize the LVGL
    tft_init();                                             //Initialize diplay 
    touchpad_init();                                        //Initialize touchpad
    ticker.attach(callback(&lv_ticker_func),TICKER_TIME);   //Attach callback to ticker

#ifdef LV_EXAMPLES_H
    printf("Demo\n"); 
    lv_demo_widgets();
#else
    printf("Hello world\n");
    lv_obj_t * label1 = lv_label_create(lv_scr_act(), NULL);
    lv_label_set_long_mode(label1, LV_LABEL_LONG_BREAK);     /*Break the long lines*/
    lv_label_set_recolor(label1, true);                      /*Enable re-coloring by commands in the text*/
    lv_label_set_align(label1, LV_LABEL_ALIGN_CENTER);       /*Center aligned lines*/
    lv_label_set_text(label1, "#0000ff Hello# #ff00ff world# #ff0000 - the LVGL and MbedOS#");
    lv_obj_set_width(label1, 150);
    lv_obj_align(label1, NULL, LV_ALIGN_IN_TOP_MID, 0, 20);

    lv_obj_t * label2 = lv_label_create(lv_scr_act(), NULL);
    lv_label_set_long_mode(label2, LV_LABEL_LONG_SROLL_CIRC);     /*Circular scroll*/
    lv_obj_set_width(label2, 150);
    lv_label_set_text(label2, "It is a circularly scrolling text. ");
    lv_obj_align(label2, NULL, LV_ALIGN_IN_BOTTOM_MID, 0, 0);
    
    lv_obj_t * label;
    lv_obj_t * btn1 = lv_btn_create(lv_scr_act(), NULL);
    lv_obj_set_event_cb(btn1, event_handler);
    lv_obj_align(btn1, NULL, LV_ALIGN_CENTER, 0, -25);
    label = lv_label_create(btn1, NULL);
    lv_label_set_text(label, "Button");
    lv_obj_t * btn2 = lv_btn_create(lv_scr_act(), NULL);
    lv_obj_set_event_cb(btn2, event_handler);
    lv_obj_align(btn2, NULL, LV_ALIGN_CENTER, 0, 25);
    lv_btn_set_checkable(btn2, true);
    lv_btn_toggle(btn2);
    lv_btn_set_fit2(btn2, LV_FIT_NONE, LV_FIT_TIGHT);
    label = lv_label_create(btn2, NULL);
    lv_label_set_text(label, "Toggled");
#endif

    while (true){
        lv_task_handler(); 
        //Call lv_task_handler() periodically every few milliseconds. 
        //It will redraw the screen if required, handle input devices etc.
        thread_sleep_for(LVGL_TICK); 
    }
}