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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

See Also

Concepts

MDI Sample: Demonstrates MDI Without Using Doc/View Architecture

CCmdUI Members

Hierarchy Chart

CCmdTarget Class