add LV_EVENT_DELETE

src/lv_core/lv_indev.c

@@ -1114,6 +1114,8 @@ static void indev_drag(lv_indev_proc_t * state)
             if(state->types.pointer.drag_in_prog == 0) {
                 drag_obj->signal_cb(drag_obj, LV_SIGNAL_DRAG_BEGIN, indev_act);
                 if(state->reset_query != 0) return;
+                lv_event_send(drag_obj, LV_EVENT_DRAG_BEGIN, NULL);
+                if(state->reset_query) return; /*The object might be deleted*/
             }
 
             state->types.pointer.drag_in_prog = 1;

src/lv_core/lv_obj.c

@@ -379,7 +379,7 @@ lv_res_t lv_obj_del(lv_obj_t * obj)
 
     if(event_act_obj == obj && event_act_obj_deleted == false) event_act_obj_deleted = true;
 
-        /*Delete from the group*/
+    /*Delete from the group*/
 #if LV_USE_GROUP
     bool was_focused = false;
     lv_group_t * group = lv_obj_get_group(obj);
@@ -410,6 +410,9 @@ lv_res_t lv_obj_del(lv_obj_t * obj)
         i = i_next;
     }
 
+    /*Let the suer free the resources used in `LV_EVENT_DELETE`*/
+    lv_event_send(obj, LV_EVENT_DELETE, NULL);
+
     /*Remove the object from parent's children list*/
     lv_obj_t * par = lv_obj_get_parent(obj);
     if(par == NULL) { /*It is a screen*/
@@ -2202,6 +2205,9 @@ static void delete_children(lv_obj_t * obj)
         i = i_next;
     }
 
+    /*Let the suer free the resources used in `LV_EVENT_DELETE`*/
+    lv_event_send(obj, LV_EVENT_DELETE, NULL);
+
     /*Remove the animations from this object*/
 #if LV_USE_ANIMATION
     lv_anim_del(obj, NULL);

src/lv_core/lv_obj.h

@@ -98,6 +98,7 @@ enum {
     LV_EVENT_REFRESH,
     LV_EVENT_APPLY,  /*"Ok", "Apply" or similar specific button has clicked*/
     LV_EVENT_CANCEL, /*"Close", "Cancel" or similar specific button has clicked*/
+    LV_EVENT_DELETE,
 };
 typedef uint8_t lv_event_t;