don't invalidate hidden objects

lv_core/lv_obj.c

@@ -343,11 +343,14 @@ void lv_obj_clean(lv_obj_t *obj)
  */
 void lv_obj_invalidate(lv_obj_t * obj)
 {
+	if(lv_obj_get_hidden(obj)) return;
+
     /*Invalidate the object only if it belongs to the 'act_scr'*/
     lv_obj_t * obj_scr = lv_obj_get_screen(obj);
     if(obj_scr == lv_scr_act() ||
        obj_scr == lv_layer_top() ||
-       obj_scr == lv_layer_sys()) {
+       obj_scr == lv_layer_sys())
+    {
         /*Truncate recursively to the parents*/
         lv_area_t area_trunc;
         lv_obj_t * par = lv_obj_get_parent(obj);
@@ -363,7 +366,8 @@ void lv_obj_invalidate(lv_obj_t * obj)
         /*Check through all parents*/
         while(par != NULL) {
             union_ok = lv_area_union(&area_trunc, &area_trunc, &par->coords);
-            if(union_ok == false) break; /*If no common parts with parent break;*/
+            if(union_ok == false) break; 		/*If no common parts with parent break;*/
+        	if(lv_obj_get_hidden(par)) return;	/*If the parent is hidden then the child is hidden and won't be drawn*/
 
             par = lv_obj_get_parent(par);
         }
@@ -750,12 +754,15 @@ void lv_obj_report_style_mod(lv_style_t * style)
  */
 void lv_obj_set_hidden(lv_obj_t * obj, bool en)
 {
+	if(!obj->hidden) lv_obj_invalidate(obj);	/*Invalidate when not hidden (hidden objects are ignored) */
+
     obj->hidden = en == false ? 0 : 1;
-    
+
+	if(!obj->hidden) lv_obj_invalidate(obj);	/*Invalidate when not hidden (hidden objects are ignored) */
+
     lv_obj_t * par = lv_obj_get_parent(obj);
     par->signal_func(par, LV_SIGNAL_CHILD_CHG, obj);
 
-    lv_obj_invalidate(obj);
 }
 
 /**