lvgl/examples/widgets/dropdown/lv_example_dropdown_3.c

#include "../../lv_examples.h"
#if LV_USE_DROPDOWN && LV_BUILD_EXAMPLES

static void event_cb(lv_event_t * e)
{
    lv_obj_t * dropdown = lv_event_get_target(e);
    char buf[64];
    lv_dropdown_get_selected_str(dropdown, buf, sizeof(buf));
    LV_LOG_USER("'%s' is selected", buf);
}

/**
 * Create a menu from a drop-down list and show some drop-down list features and styling
 */
void lv_example_dropdown_3(void)
{
    /*Create a drop down list*/
    lv_obj_t * dropdown = lv_dropdown_create(lv_screen_active());
    lv_obj_align(dropdown, LV_ALIGN_TOP_LEFT, 10, 10);
    lv_dropdown_set_options(dropdown, "New project\n"
                            "New file\n"
                            "Save\n"
                            "Save as ...\n"
                            "Open project\n"
                            "Recent projects\n"
                            "Preferences\n"
                            "Exit");

    /*Set a fixed text to display on the button of the drop-down list*/
    lv_dropdown_set_text(dropdown, "Menu");

    /*Use a custom image as down icon and flip it when the list is opened*/
    LV_IMAGE_DECLARE(img_caret_down);
    lv_dropdown_set_symbol(dropdown, &img_caret_down);
    lv_obj_set_style_transform_rotation(dropdown, 1800, LV_PART_INDICATOR | LV_STATE_CHECKED);

    /*In a menu we don't need to show the last clicked item*/
    lv_dropdown_set_selected_highlight(dropdown, false);

    lv_obj_add_event(dropdown, event_cb, LV_EVENT_VALUE_CHANGED, NULL);
}

#endif