The value set control is similar to the existing radio button control since its purpose is to allow a user to select an item from an existing set. However, unlike radio buttons, the value set provides a graphical set of selectable items. Suppose an application, like the one shown in Figure "Value Set Control", provides the ability to select a drawing tool. Using the value set, the application can provide a graphical image of the different tools so that the user can see all the available choices when he makes his selection.
The value set control offers great flexibility to the interface designer because it can be extended as the application grows. The system drag protocol is supported by the value set control. This means that users could, for example, select a color from a value set and then drag that color to the target item. For example, he could drag the color to the client area of a window to change that window's background color.
The items within a value set control may include:
Items of different types may be mixed in the same value set control.
While a value set control may be used to display textual or numeric data, it is recommended that a radio button be used for this purpose, and that the use of the value set control be confined to the display of graphical data.