How to create MDI child forms at runtime and a button for each of them in the parent form

Hi!

Do you know the WindowMenu property of a (parent) form?
It links to a menu that list all current MDI children of an application.

I want to list all existing children also in other place. More exactly I want to create an interface similar with Macromedia Dreamweaver or Delphi 7, where each MDI child has its own tab from where it can be quickly accessed.

I started the work from TForm.Notification but something is wrong.
The idea was to create a new tab in a TPageControl every time a form was created at runtime.
Somebody came with idea of adding a routine in each MDI form (in Create and Destroy) but I don't like the idea because I have many different forms derived from TFrom in my application.

The code that I tried is:


VAR  
    Initializing: Boolean= True;
    FormID: Integer= 0;

procedure TfrmMain.Button1Click(Sender: TObject);
VAR F: TForm;
begin
 F:= TForm.Create(Self);
 F.Caption:= 'xx';
 F.Name:= 'Form'+ i2s(FormID);
 F.Tag:= FormID;  
 F.FormStyle:= fsMDIChild;
 F.Show;
 F.BringToFront;
end;


procedure TfrmMain.FormCreate(Sender: TObject);
begin
   Initializing:= FALSE;
end;


procedure TfrmMain.Notification(AComponent: TComponent; Operation: TOperation);
VAR btn: TButton;
begin
 inherited;
 if NOT Initializing
 AND (Operation= opInsert)
 AND (AComponent is TForm)
 then
  begin
   inc(FormID);
     
   btn:= TButton.Create(Self);
   btn.Parent:= Self;
   btn.Visible:= TRUE;
   btn.BringToFront;
   btn.Top := 1;
   btn.Caption:=  (AComponent as TForm).Caption;    <--- AV here
   btn.Tag:= FormID;
   AComponent.Tag:= FormID;
  end;

if  (Operation= opRemove) then RemoveAsocButton;
end;


The code creates a MDI child when you push the button.
At this moment the Notification is aware that a new component is ready to be created. Here I want to create the list of existing MDI children (the above code tries to create a button for each of these MDI children). However it fails when at this line (AComponent as TForm).Caption.
The AComponent seems to be un-initialized.

PS: I also need the routine that deletes the corresponding button when its MDI child is closed.
PS: I accept also other approaches as long as they are elegant (for example if I dont need to insert code in all my derived forms). Maybe to create a MDI child and set a tab (TTabSheet) as its parent.
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