unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs;
type
TForm1 = class(TForm)
procedure FormShow(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
private
{ Private declarations }
public
{ Public declarations }
FClientInstance : TFarProc;
FPrevClientProc : TFarProc;
procedure ClientWndProc(var aMessage: TMessage);
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
{ TForm1 }
procedure TForm1.ClientWndProc(var aMessage: TMessage);
begin
case aMessage.Msg of
WM_MDICreate :
begin
aMessage.Result := CallWindowProc(FPrevClientProc,ClientHandle, aMessage.Msg, aMessage.wParam, aMessage.lParam);
end;
WM_MDIDESTROY:
begin
aMessage.Result := CallWindowProc(FPrevClientProc,ClientHandle, aMessage.Msg, aMessage.wParam, aMessage.lParam);
showmessage( 'WM_MDIDESTROY' );
end;
else
aMessage.Result := CallWindowProc(FPrevClientProc,ClientHandle, aMessage.Msg, aMessage.wParam, aMessage.lParam);
end;
end;
procedure TForm1.FormShow(Sender: TObject);
begin
FPrevClientProc := Pointer(GetWindowLong(ClientHandle, GWL_WNDPROC));
FClientInstance := MakeObjectInstance(ClientWndProc);
SetWindowLong(ClientHandle, GWL_WNDPROC, LongInt(FClientInstance));
end;
procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
SetWindowLong(ClientHandle, GWL_WNDPROC, LongInt(FPrevClientProc));
end;
end.
