Klick auf Button simulieren nach dem Scrollen?

[thomas2009]

Ich wollte nun einen Scrollbar statt Trackbar verwenden
Ich habe einfach das Wort Trackbar mit Scrollbar ersetzt aber es hat nicht geklappt !
Was muss ich noch ändern ?

Delphi-Quellcode:

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ComCtrls, CommCtrl, StdCtrls;
// uses : CommCtrl

// TScrollBar um ein OnChanged Ereignis erweitern
type
  TScrollBar = class(ComCtrls.TScrollBar)
  private
    FOnChanged : TNotifyEvent;
    procedure CNHScroll(var msg: TWMHScroll); message CN_HSCROLL;
  published
    property OnChanged: TNotifyEvent read FOnChanged write FOnChanged;
    property OnMouseDown;
    property OnMouseUp;
    property OnClick;
  public
end;


  type
  TForm1 = class(TForm)
    Memo1: TMemo;
    ListBox1: TListBox;
    ScrollBar1: TScrollBar;
    procedure FormCreate(Sender: TObject);
  private
  procedure ScrollBarChanged(Sender: TObject);
    procedure ScrollBarMouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
    procedure ScrollBarMouseUp(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
    procedure ScrollBarClick(Sender: TObject);
  public
  end;



var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TScrollBar.CNHScroll(var msg: TWMHScroll);
begin
  inherited;
  if Assigned(fOnChanged) then
    if (msg.ScrollCode in [TB_THUMBPOSITION, TB_LINEUP, TB_LINEDOWN, TB_PAGEUP, TB_PAGEDOWN]) then
    begin
       FOnChanged(Self);
    end;
end;

procedure TForm1.ScrollBarChanged(Sender: TObject);
begin
  ListBox1.Items.Add('Position geändert ! ');
end;

procedure TForm1.ScrollBarMouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
begin
  ListBox1.Items.Add('ScrollBar OnMouseDown');
end;

procedure TForm1.ScrollBarMouseUp(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
begin
  ListBox1.Items.Add('ScrollBar OnMouseUp');
end;

procedure TForm1.ScrollBarClick(Sender: TObject);
begin
ListBox1.Items.Add('ScrollBar OnClick');
end; 

procedure TForm1.FormCreate(Sender: TObject);
begin
  ScrollBar1.OnChanged := ScrollBarChanged;
  ScrollBar1.OnMouseDown := ScrollBarMouseDown;
  ScrollBar1.OnMouseUp := ScrollBarMouseUp;
  ScrollBar1.OnClick := ScrollBarClick;
end;

end.