fixed #556

src/Shared/HandyControl_Shared/Controls/Growl/Growl.cs

@@ -321,6 +321,8 @@ namespace HandyControl.Controls
 
         private void Update()
         {
+            if (DesignerHelper.IsInDesignMode) return;
+
             if (Type == InfoType.Ask)
             {
                 _panelMore.IsEnabled = true;

src/Shared/HandyControl_Shared/Controls/Other/Drawer.cs

@@ -259,7 +259,7 @@ namespace HandyControl.Controls
 
         private void OnIsOpenChanged(bool isOpen)
         {
-            if (Content == null) return;
+            if (Content == null || DesignerHelper.IsInDesignMode) return;
 
             _window = WindowHelper.GetActiveWindow();
             if (_window == null) return;