properly fixed notificaitons for theme changed, closes #5774

scene/gui/control.cpp

@@ -1865,7 +1865,7 @@ void Control::_modal_stack_remove() {
 
 }
 
-void Control::_propagate_theme_changed(CanvasItem *p_at,Control *p_owner) {
+void Control::_propagate_theme_changed(CanvasItem *p_at,Control *p_owner,bool p_assign) {
 
 	Control *c = p_at->cast_to<Control>();
 
@@ -1884,15 +1884,30 @@ void Control::_propagate_theme_changed(CanvasItem *p_at,Control *p_owner) {
 
 	if (c) {
 
-		c->data.theme_owner=p_owner;
+		if (p_assign) {
+			c->data.theme_owner=p_owner;
+		}
 		c->_notification(NOTIFICATION_THEME_CHANGED);
 		c->update();
 	}
 }
 
+
+void Control::_theme_changed() {
+
+	_propagate_theme_changed(this,this,false);
+}
+
 void Control::set_theme(const Ref<Theme>& p_theme) {
 
 
+	if (data.theme==p_theme)
+		return;
+
+	if (data.theme.is_valid()) {
+		data.theme->disconnect("changed",this,"_theme_changed");
+	}
+
 	data.theme=p_theme;
 	if (!p_theme.is_null()) {
 
@@ -1909,6 +1924,9 @@ void Control::set_theme(const Ref<Theme>& p_theme) {
 
 	}
 
+	if (data.theme.is_valid()) {
+		data.theme->connect("changed",this,"_theme_changed");
+	}
 
 }
 
@@ -2448,6 +2466,10 @@ void Control::_bind_methods() {
 
 	ObjectTypeDB::bind_method(_MD("minimum_size_changed"), &Control::minimum_size_changed);
 
+	ObjectTypeDB::bind_method(_MD("_theme_changed"), &Control::_theme_changed);
+
+
+
 	ObjectTypeDB::bind_method(_MD("_font_changed"), &Control::_font_changed);
 
 	BIND_VMETHOD(MethodInfo("_input_event",PropertyInfo(Variant::INPUT_EVENT,"event")));

scene/gui/control.h

@@ -172,7 +172,9 @@ private:
 	float _get_range(int p_idx) const;
 	float _s2a(float p_val, AnchorType p_anchor,float p_range) const;
 	float _a2s(float p_val, AnchorType p_anchor,float p_range) const;
-	void _propagate_theme_changed(CanvasItem *p_at, Control *p_owner);
+	void _propagate_theme_changed(CanvasItem *p_at, Control *p_owner, bool p_assign=true);
+	void _theme_changed();
+
 
 	void _change_notify_margins();
 	void _update_minimum_size();

scene/resources/theme.cpp

@@ -219,7 +219,22 @@ Ref<Theme> Theme::get_default() {
 
 void Theme::set_default_theme_font( const Ref<Font>& p_default_font ) {
 
+	if (default_theme_font==p_default_font)
+		return;
+
+	if (default_theme_font.is_valid()) {
+		_unref_font(default_theme_font);
+	}
+
 	default_theme_font=p_default_font;
+
+	if (default_theme_font.is_valid()) {
+		_ref_font(default_theme_font);
+	}
+
+	_change_notify();
+	emit_changed();;
+
 }
 
 Ref<Font> Theme::get_default_theme_font() const {