TdxAlertWindowManager.OnCustomDrawBackground Event
Enables you to custom paint an alert window‘s background.
Declaration
property OnCustomDrawBackground: TdxAlertWindowManagerCustomDrawBackgroundEvent read; write;
Remarks
Sender
specifies the alert window manager that fired the event.
AAlertWindow
specifies the alert window being custom painted.
ACanvas
specifies the drawing surface.
AViewInfo
provides ViewInfo information (a TdxAlertWindowViewInfo class instance) used to paint the alert window’s background. Refer to the TdxAlertWindowHitTest.HitBackground property description to learn about the main TdxAlertWindowViewInfo
properties accessible via AViewInfo that you can use for custom painting.
ADone
specifies whether default painting is required. Set ADone
to True
, to prevent default code execution.
The following code snippet demonstrates how to handle the OnCustomDrawBackground
event to custom paint an alert window’s background to help end-users discern messages displayed in this window.
const
cxBackColorMap: array[0..3] of TColor = (clLtGray, clMedGray, clDkGray, clMedGray);
procedure <Form>.<dxAlertWindowManager>CustomDrawBackground(Sender: TObject; AAlertWindow: TdxAlertWindow; ACanvas: TcxCanvas; AViewInfo: TdxAlertWindowViewInfo; var ADone: Boolean);
begin
ACanvas.FillRect(AViewInfo.Bounds, cxBackColorMap[AAlertWindow.CurrentMessageIndex mod 4]);
ADone := True;
end;