Create a class for the custom widget

The backbone of the designer is a custom widget. It allows you to wrap existing designer views into a multi-view designer. The custom widget can reside either in the project of the targeted widget or in a separate project. Because the designers are usually coupled with a specific widget, we recommended creating the designer in the same project as the widget. 

To create the class for the designer, perform the following.

1. Add a new class to the project of the targeted widget.
   For example, if your widget is named MultiViewWidget, create a class named MultiViewWidgetDesigner.cs
   Perform the following:
   1. In the context menu of References, click Add Reference...
   2. Click Browse tab and navigate to folder C:\Program Files (x86)\Telerik\Sitefinity CMS\Libraries.
   3. Select the assembly and click OK.
2. Add a reference to the System.Web.Extensions assembly.
   Perform the following
   1. In the context menu of References, click Add Reference...
   2. Click the .NET tab, select the assembly, and click OK.
3. Add statement using Telerik.Sitefinity.Web.UI.ControlDesign; to the RotatorDesigner class.
4. Make the MultiViewWidgetDesigner class inherit the ContentViewDesignerBase class.