CCmdUI Class
Is used only within an ON_UPDATE_COMMAND_UI handler in a CCmdTarget-derived class.
class CCmdUI
Remarks
CCmdUI does not have a base class.
When a user of your application pulls down a menu, each menu item needs to know whether it should be displayed as enabled or disabled. The target of a menu command provides this information by implementing an ON_UPDATE_COMMAND_UI handler. For each of the command user-interface objects in your application, use the Properties window to create a message-map entry and function prototype for each handler.
When the menu is pulled down, the framework searches for and calls each ON_UPDATE_COMMAND_UI handler, each handler calls CCmdUI member functions such as Enable and Check, and the framework then appropriately displays each menu item.
A menu item can be replaced with a control-bar button or other command user-interface object without changing the code within the ON_UPDATE_COMMAND_UI handler.
The following table summarizes the effect CCmdUI's member functions have on various command user-interface items.
User-Interface Item |
Enable |
SetCheck |
SetRadio |
SetText |
|---|---|---|---|---|
Menu item |
Enables or disables |
Checks (×) or unchecks |
Checks using dot (•) |
Sets item text |
Toolbar button |
Enables or disables |
Selects, unselects, or indeterminate |
Same as SetCheck |
(Not applicable) |
Status-bar pane |
Makes text visible or invisible |
Sets pop-out or normal border |
Same as SetCheck |
Sets pane text |
Normal button in CDialogBar |
Enables or disables |
Checks or unchecks check box |
Same as SetCheck |
Sets button text |
Normal control in CDialogBar |
Enables or disables |
(Not applicable) |
(Not applicable) |
Sets window text |
For more on the use of this class, see How to Update User-Interface Objects.
Requirements
Header: afxwin.h