Общие вопросы

Code:

type

  //...

private

   { Private declarations }

   procedure WMNCACTIVATE(var M: TWMNCACTIVATE); message WM_NCACTIVATE;

end;

implementation

//...

procedure TForm1.WMNCACTIVATE(var M: TWMNCACTIVATE);

begin

inherited;

if M.Active then

   caption:='Form active'

else caption:='Form not active' ;

end;