TControl.EnabledChanging procedure

Declaration

procedure EnabledChanging; virtual

Description

EnabledChanging is called when a new value has been assigned to the Enabled property. It occurs after the new property value is stored to its member, and before a CM_ENABLEDCHANGED control message is posted for the control. It allows all of the TNotifyEvent routines registered for the chtOnEnabledChanging control handler type to be signalled for the new property value.

EnabledChanging calls the DoCallNotifyHandler method to signal each of the handler routines using the chtOnEnabledChanging control handler type. The class instance is used as the Sender argument for the event notification.

Use RemoveHandlerOnEnabledChanging to manage the TNotifyEvent handler routines for the handler type used in the control. AddHandler and RemoveHandler can be used if the control handler type is passed as an argument.

See EnabledChanged for the actions performed after the value in Enabled is updated.

See also

• Enabled
• EnabledChanged
• Perform
• DoCallNotifyHandler
• TControlHandlerType
• TNotifyEvent