unit MDIBkgndDemoChld; interface uses Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, JvBackgrounds, MDIBkgndDemoMain, Buttons; type TMDIChildForm = class(TForm) BackgroundSwitch: TSpeedButton; procedure BackgroundSwitchClick(Sender: TObject); private { Private declarations } public { Public declarations } end; var MDIChildForm: TMDIChildForm; implementation {$R *.DFM} procedure TMDIChildForm.BackgroundSwitchClick(Sender: TObject); begin if BackgroundSwitch.Down then MDIMainForm.Background.Clients.Add(Self) else MDIMainForm.Background.Clients.Remove(Self); end; end.