Image dem Mousezeiger folgen

[semo]

und wer es ganz ohne komponenten mag:

Delphi-Quellcode:

unit frmMain;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, jpeg, ExtCtrls, StdCtrls;

type
  TForm1 = class(TForm)
    Image1: TImage;
    Button1: TButton;
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
    procedure MessageEventHandler(var Msg: TMsg; var Handled: Boolean);
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
  Application.OnMessage := MessageEventHandler;
end;

procedure TForm1.MessageEventHandler(var Msg: TMsg; var Handled: Boolean);
begin
  case Msg.message of
    WM_MOUSEMOVE:
      begin
        Invalidate();
      end;

    WM_PAINT:
      begin
        Image1.Left := Round(ScreenToClient(Mouse.CursorPos).X - Image1.Width / 2);
        Image1.Top  := Round(ScreenToClient(Mouse.CursorPos).Y - Image1.Height / 2);
      end;
  end;
end;