Since all value set items are mutually exclusive, only one of them can be selected at a time. Therefore, the only type of selection supported by the value set control is single selection.
Note: If more than one value set window is open, navigating to and selecting items in one value set window has no affect on the items displayed in any other value set window.
An initial choice is selected when the value set control is first displayed. If the application does not provide the initial selection by using the VM_SELECTITEM message, the choice in row 1, column 1 is selected automatically.
The value set control supports the use of a pointing device, such as a mouse, and the keyboard for navigating to and selecting items, except for items that are dimmed on the screen. This dimming of items is called unavailable-state emphasis and indicates that the items cannot be selected. However, the selection cursor, a dotted outline that usually indicates that an item can be selected, can be moved to unavailable items so that a user can press F1 to determine why they cannot be selected. The following sections describe the pointing device and keyboard support for the value set control.