efl_ui_widget: reintroduce legacy behaviour

before the refactoring of the disabled property, there was no way to
enable a widget which has a disabled tree. This here however enables
this to work again like this. The user will be told with an error
message. The integraty of the property is maintained accross reparents.

Reviewed-by: Jaehyun Cho <jae_hyun.cho@samsung.com>
Differential Revision: https://phab.enlightenment.org/D8459

src/lib/elementary/efl_ui_widget.c

@@ -1361,6 +1361,35 @@ elm_widget_sub_object_parent_add(Evas_Object *sobj)
    return elm_widget_sub_object_add(parent, sobj);
 }
 
+static int
+_disabled_counter_get(Eo *widget)
+{
+   ELM_WIDGET_DATA_GET_OR_RETURN(widget, pd, -1);
+
+   return pd->disabled;
+}
+
+static void
+_mirror_disabled_state(Eo *obj, Elm_Widget_Smart_Data *pd, int disabled_delta)
+{
+   pd->disabled = (pd->parent_obj ? _disabled_counter_get(pd->parent_obj) : 0) + disabled_delta;
+
+   //we should not call disabled_set when things are invalidated
+   //otherwise we will unleashe an amount of errors in efl_ui_layout
+   if (efl_invalidated_get(obj)) return;
+
+   if (pd->disabled > 0)
+     {
+        pd->disabled --;
+        efl_ui_widget_disabled_set(obj, EINA_TRUE);
+     }
+   else
+     {
+        pd->disabled ++;
+        efl_ui_widget_disabled_set(obj, EINA_FALSE);
+     }
+}
+
 EOLIAN static void
 _efl_ui_widget_widget_parent_set(Eo *obj, Elm_Widget_Smart_Data *pd, Efl_Ui_Widget *parent)
 {
@@ -1384,6 +1413,7 @@ _efl_ui_widget_widget_parent_set(Eo *obj, Elm_Widget_Smart_Data *pd, Efl_Ui_Widg
    double scale, prev_scale = efl_gfx_entity_scale_get(obj);
    Elm_Theme *th, *prev_th = elm_widget_theme_get(obj);
    Eina_Bool mirrored, pmirrored = efl_ui_mirrored_get(parent);
+   int disabled_delta = pd->disabled - (pd->parent_obj ? _disabled_counter_get(pd->parent_obj) : 0);
 
    old_parent = pd->parent_obj;
    pd->parent_obj = parent;
@@ -1403,10 +1433,9 @@ _efl_ui_widget_widget_parent_set(Eo *obj, Elm_Widget_Smart_Data *pd, Efl_Ui_Widg
           }
         if (_is_focused(obj)) _parents_focus(parent);
         elm_widget_display_mode_set(obj, evas_object_size_hint_display_mode_get(parent));
-        elm_widget_disabled_set(obj, efl_ui_widget_disabled_get(parent));
         _elm_widget_top_win_focused_set(obj, _elm_widget_top_win_focused_get(parent));
      }
-
+   _mirror_disabled_state(obj, pd, disabled_delta);
    _full_eval(obj, pd);
 
    if (old_parent && _elm_config->atspi_mode)
@@ -2309,11 +2338,20 @@ _efl_ui_widget_disabled_set(Eo *obj EINA_UNUSED, Elm_Widget_Smart_Data *pd, Eina
 {
    Efl_Ui_Widget *subs;
    Eina_List *n;
+   int distance, parent_counter = (pd->parent_obj ? _disabled_counter_get(pd->parent_obj) : 0);
 
    if (disabled)
      pd->disabled ++;
    else
-     pd->disabled = MAX(pd->disabled - 1 ,0);
+     pd->disabled --;
+
+   distance = pd->disabled - parent_counter;
+
+   if ((distance < 0) || (distance > 1))
+     {
+        distance = MAX(MIN(disabled, 1), 0);
+        pd->disabled = parent_counter + distance;
+     }
 
    EINA_LIST_FOREACH(pd->subobjs, n, subs)
      {

src/tests/elementary/efl_ui_test_widget.c

@@ -285,6 +285,42 @@ EFL_START_TEST(efl_ui_test_widget_disabled_parent)
 }
 EFL_END_TEST
 
+EFL_START_TEST(efl_ui_test_widget_disabled_behaviour)
+{
+   Efl_Ui_Win *win, *w1, *w2, *t;
+
+   win = efl_add(EFL_UI_WIN_CLASS, efl_main_loop_get(),
+                 efl_ui_win_type_set(efl_added, EFL_UI_WIN_TYPE_BASIC),
+                 efl_text_set(efl_added, "Hello World"));
+   //first check the initial state
+   w1 = efl_add(efl_ui_widget_realized_class_get(), win);
+   efl_ui_widget_disabled_set(w1, EINA_TRUE);
+   w2 = efl_add(efl_ui_widget_realized_class_get(), win);
+   efl_ui_widget_disabled_set(w2, EINA_FALSE);
+
+
+   t = efl_add(efl_ui_widget_realized_class_get(), win);
+   efl_ui_widget_sub_object_add(w1, t);
+   //check that we never enable something under disabled parent
+   DISABLE_ABORT_ON_CRITICAL_START;
+   efl_ui_widget_disabled_set(t, EINA_FALSE);
+   DISABLE_ABORT_ON_CRITICAL_END;
+   ck_assert_int_eq(efl_ui_widget_disabled_get(t), EINA_TRUE);
+   efl_del(t);
+
+   t = efl_add(efl_ui_widget_realized_class_get(), win);
+   efl_ui_widget_sub_object_add(w1, t);
+   //check that we can disable something with a disabled tree
+   efl_ui_widget_disabled_set(t, EINA_TRUE);
+   ck_assert_int_eq(efl_ui_widget_disabled_get(t), EINA_TRUE);
+   efl_ui_widget_sub_object_add(w2, t);
+   ck_assert_int_eq(efl_ui_widget_disabled_get(t), EINA_TRUE);
+   efl_del(t);
+
+   efl_del(win);
+}
+EFL_END_TEST
+
 static int tree_abort;
 static int tree_abort_level;
 
@@ -316,4 +352,5 @@ void efl_ui_test_widget(TCase *tc)
    tcase_add_test(tc, efl_ui_test_widget_sub_object_theme_sync);
    tcase_add_test(tc, efl_ui_test_widget_parent_relation);
    tcase_add_test(tc, efl_ui_test_widget_disabled_parent);
+   tcase_add_test(tc, efl_ui_test_widget_disabled_behaviour);
 }