Warum ist diese TGraphicControl nicht zu sehen?

[berens]

Man ersetze TGraphicControl durch TWinControl und es funktioniert. Warum nicht mit TGraphicControl?

Warum ist diese TGraphicControl nicht zu sehen?

Delphi-Quellcode:

type Tblabla= class(TGraphicControl)
  private
  public
    constructor Create(aOwner: TComponent); override;
  end;

implementation

constructor Tblabla.Create(aOwner: TComponent);
begin
  inherited Create(aOwner);
  if aOwner is TWinControl then begin
    Parent := (aOwner as TWinControl);
  end;
  ControlStyle := [csClickEvents,csCaptureMouse];
  Left := 10;
  Top := 10;
  Height := 100;
  Width := 100;
  ParentColor := false;
  Visible := true;
  with tlabel.Create(aowner) do begin
    left := 5;
    top := 5;
    width := 2000;
    height := 20000;
    color := clred;
    AutoSize := false;
    parent := (aowner as twincontrol);
    caption := 'XXXXXXXXXXXXXXXXXXXXXXXXXXX';
    BringToFront;
  end;
//  Align := alClient;

  Color := clYellow;

  Self.Parent := aowner as TWinControl;


  Self.Show;

  Canvas.Lock;
  canvas.Brush.Color := cllime;
  Canvas.FillRect(rect(10,10,10,10));
  canvas.Unlock;
  Paint;

  Refresh;
  update;
  BringToFront;
  Repaint;
  Invalidate;
  Self.Parent := aowner as TWinControl;
end;

--------------------------------------------------------
Unit1:
procedure TForm1.FormCreate(Sender: TObject);
begin
  n := Tblabla.Create(Self);
  n.Parent := Self;
end;

[Kroko1999]

so sollte es gehen!

Delphi-Quellcode:

type Tblabla= class(TGraphicControl)
  private
  protected
    procedure Paint; override;
  public
    constructor Create(aOwner: TComponent); override;
  end;

implementation

constructor Tblabla.Create(aOwner: TComponent);
begin
  inherited Create(aOwner);
  Height := 100;
  Width := 100;
  ParentColor := false;
  with tlabel.Create(aowner) do begin
    left := 5;
    top := 5;
    width := 2000;
    height := 20000;
    color := clred;
    AutoSize := false;
    parent := Self;
    caption := 'XXXXXXXXXXXXXXXXXXXXXXXXXXX';
    BringToFront;
  end;
//  Align := alClient;

  Color := clYellow;
end;

procedure TBlabla.Paint; override;
begin
  inherited;
  Canvas.Lock;
  canvas.Brush.Color := cllime;
  Canvas.FillRect(rect(10,10,10,10));
  canvas.Unlock;
end;
--------------------------------------------------------
Unit1:
procedure TForm1.FormCreate(Sender: TObject);
begin
  n := Tblabla.Create(Self);
  n.Parent := Self;
end;

[berens]

Hat geklappt, danke.