[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] | Reference for unit 'Forms' (#lcl)

# TCustomForm.OnDeactivate

Handler signalled when the form is deactivated (loses focus).

## Declaration

Source position: forms.pp line 804

`public property TCustomForm.OnDeactivate : TNotifyEvent read FOnDeactivate write FOnDeactivate;`

## Description

OnDeactivate is a TNotifyEvent property which contains an event handler signalled when a form is deactivated (loses focus). OnDeactivate is signalled from the Deactivate method (when assigned), and occurs when the CM_DEACTIVATE message is handled in the CMDeactivate method. OnDeactivate is signalled each time the focus is changed from the current form instance to another form instance in the application.

## See also

TCustomForm.Deactivate |  | Performs actions when the form loses focus.
TCustomForm.WMActivate |  | Handles the LM_ACTIVATE message which activates or deactivates the form.
TCustomForm.OnActivate |  | Handler signalled when the form instance receives focus.
TCustomForm.OnShow |  | Handler called when the form becomes visible.
TCustomForm.OnHide |  | Handler called when the form is being hidden.
TApplication.OnDeactivate |  | Event handler signalled when a Deactivate message is handled in the application.