Focus issue when switching screens

How-to
,
1

Focus not updating automatically when switching screens

Description

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

PC simulator

What LVGL version are you using?

v9.2

What do you want to achieve?

I want to switch from one screen to another using lv_screen_load_anim(), and I expect the focus to move automatically to the new screen while being removed from the old one.

What have you tried so far?

I noticed that when changing screens with lv_screen_load_anim(), the previous screen does not lose focus, and the new screen does not gain focus automatically. I had to explicitly call lv_group_focus_obj() to set focus on a widget in the new screen.

Is this the intended behavior, or am I missing something? Should LVGL handle this automatically when switching screens?

Code to reproduce

Here is a minimal example:

void _ui_screen_change(lv_obj_t **target, lv_screen_load_anim_t fademode, int spd, int delay,
                       void (*target_init)(void)) 
{
    if (*target == NULL)
        target_init();

    lv_scr_load_anim(*target, fademode, spd, delay, false);

    if (ui_Screen_1 == *g->obj_focus)
        LOG("ui_Screen_1");
    if (ui_Screen_2 == *g->obj_focus)
        LOG("ui_Screen_2");
    if (ui_Screen_3 == *g->obj_focus)
        LOG("ui_Screen_3");
}

I expected obj_focus to point to a widget on the newly loaded screen, but it seems to retain focus from the previous screen.

Should I manually manage focus when switching screens, or is there a built-in way to handle this automatically?