Comment ecrire un code pour basculer entre d'

voila mon ami

unit Unit1;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
StdCtrls;
type
TForm1 = class(TForm)
Edit1: TEdit;
Edit2: TEdit;
Edit3: TEdit;
procedure Edit1Exit(Sender: TObject);
private
{ Déclarations privées }
public
{ Déclarations publiques }
end;
var
Form1: TForm1; implementation
{$R *.DFM}
procedure TForm1.Edit1Exit(Sender: TObject);
begin
if (sender is TEdit) then
case (sender as tedit).Tag of
2:
begin
LoadKeyboardLayout('0000040c', KLF_ACTIVATE); //// Francais france
Application.BiDiKeyboard := '0000040c';
end;
1,3:
begin
LoadKeyboardLayout('00001401', KLF_ACTIVATE);//// Arabe Algerie
Application.BiDiKeyboard := '00001401';
end;
end;
end;
end.