How do I keep a drop-down list open and in edit mode after making a selection?

How-to
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1

Description

I want to make a multi-page drop-down list that is navigated with an encoder. Whenever an option is selected, the list should repopulate with a new set of options and reset the selected option to 0.

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

nRF52840

What LVGL version are you using?

8.2

What do you want to achieve?

I want the list to remain open and the widget to remain in edit mode (so the next set of options can be scrolled through and a second selection can be made) after the first selection is made. With the code below, the list repopulates and stays open after clicking on option 2 but turning the encoder afterwards changes to a different widget in the encoder group and closes the list instead of changing to a different selection in the list. The drop-down list seems to no longer be in an edit state.

What have you tried so far?

I’ve tried to manually add various states (checked and edited) to the drop-down after an event callback (LV_EVENT_RELEASED, LV_EVENT_VALUE_CHANGED, and LV_EVENT_CANCEL).

Code to reproduce

static void event_cb(lv_event_t *e) {
  static bool load_next = false;
  if (code == LV_EVENT_VALUE_CHANGED) {
    if (lv_dropdown_get_selected(dd) == 2) { // TODO should only apply for first list
        load_next = true;
      }
    }
  else if (code == LV_EVENT_RELEASED) {
    if (load_next == true) { // TODO else load original options
      load_next = false; 
      lv_dropdown_set_options(dd, "F\n" "G\n" "H\n" "I\n" "J");
      lv_dropdown_set_selected(dd, 0);
      lv_dropdown_open(dd);
      lv_obj_add_state(dd, LV_STATE_CHECKED);
      lv_obj_add_state(dd, LV_STATE_EDITED);
    }
  }
}

...
void main(void)
{
  dd = lv_dropdown_create(lv_scr_act());
  lv_obj_align(dd, LV_ALIGN_CENTER, 0, 0);
  lv_dropdown_set_options(dd, "A\n" "B\n" "C\n" "D\n" "E");
  lv_obj_add_event_cb(dd, event_cb, LV_EVENT_ALL, NULL);
  ...
}

Screenshot and/or video

Sequence of encoder inputs in the video is click → right turn → right turn → click → right turn. The leaf is a fake cursor I added as a visual indicator for the group object the encoder is currently focused on.