Vcl.Controls.TControl.VisibleChanging
Delphi
procedure VisibleChanging; dynamic;
C++
DYNAMIC void __fastcall VisibleChanging(void);
Properties
| Type | Visibility | Source | Unit | Parent | 
|---|---|---|---|---|
| procedure function | protected | Vcl.Controls.pas Vcl.Controls.hpp | Vcl.Controls | TControl | 
Description
Provides the interface for a method that responds to changes in the control's visibility.
VisibleChanging is called before the value of a control's Visible property changes. As implemented in TControl, it does nothing. Override VisibleChanging to respond to changes in the control's visibility. For example, if a control should not change its visibility, override VisibleChanging to raise an exception when an attempt is made to alter the control's visibility.