CONTROL+TAB en PAGECONTROL dentro de MDI-CHILD

[amadis]

CONTROL+TAB en PAGECONTROL dentro de MDI-CHILD

El titulo lo dice todo!

Deseo utilizar CONTROL+TAB en un PAGECONTROL que está dentro de MDI-CHILD y en lugar de cambiar de tabsheet cambia se mdi activo (en el caso de que haya 2 mdi creado sino no hace nada)

No he visto nada en el foro sobre esto!

Pero he encontrado un trozo de codigo que no comprendí y no pude usar que segun dice sirve para solucionar mi problema!

Les agradeceria su ayuda
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To get around this one needs to intervene before IsMDIMsg is even called. There is only one opportunity to do this: the Application.OnMessage event. So add a handler for the main form OnCreate event, and add a private method to the form called AppMessage:

Código Delphi [-]

procedure TMainForm.FormCreate(Sender: TObject);
begin
  Application.OnMessage := AppMessage;
end;

procedure TMainform.Appmessage(var Msg: TMsg; var Handled: Boolean);
var
  message: TWMKey;
begin
  if (msg.message = WM_KEYDOWN) and (LoWord(msg.wparam) = VK_TAB) and
    (GetKeyState(VK_CONTROL) < 0) and Assigned(ActiveMDIChild) then
  begin
    Move(msg.message, message.msg, 3 * sizeof(Cardinal));
    message.result := 0;
    Handled := ActiveMDIChild.IsShortcut(message);
  end;
end;

This will redirect Ctrl+Tab (and Ctrl+Shift+Tab) to the active MDI childs IsShortcut function. This fires the OnShortcut event, so we can use that event on the child form to further handle the key event:

Código Delphi [-]
function IsOnTabsheet(aControl: TWinControl; var pc: TPageControl): Boolean;
begin
  while Assigned(aControl) and not (aControl is TTabsheet) do
    aControl := aControl.Parent;
  Result := Assigned(aControl);
  if result then
    pc := TTabSheet(aControl).Pagecontrol;
end;

procedure TMDIChild.FormShortCut(var Msg: TWMKey; var Handled: Boolean);
var
  pc: TPageControl;
begin
  if (msg.CharCode = VK_TAB) and (GetKeyState(VK_CONTROL) < 0) then
  begin
    if IsOnTabsheet(ActiveControl, pc) then
    begin
      pc.Perform(CM_DIALOGKEY, msg.CharCode, 0);
      Handled := true;
    end;
  end;
end;

Desde ya Gracias