interfaceuses  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,  Dialogs;type  TMsgReceiver = class(TObject)  private    fMsgHandlerHWND : HWND;    WM_MY_UNIQUE_MESSAGE : Cardinal;    procedure WndMethod(var Msg: TMessage);  public    Point : TPoint;    constructor Create;    destructor Destroy; override;  end;  TClickSendForm = class(TForm)    procedure FormCreate(Sender: TObject);    procedure FormMouseDown(Sender: TObject; Button: TMouseButton;  Shift: TShiftState; X, Y: Integer);    procedure FormDestroy(Sender: TObject);  private    WM_MY_UNIQUE_MESSAGE : Cardinal;    fMsgReceiver: TMsgReceiver;    function GetMsgReceiver: TMsgReceiver;    property MsgReceiver : TMsgReceiver read GetMsgReceiver;  public    {
      Public declarations }  end;var  ClickSendForm: TClickSendForm;implementation{
     $R *.dfm}procedure TClickSendForm.FormCreate(Sender: TObject);begin  //instantiate MsgReceiver  MsgReceiver;  WM_MY_UNIQUE_MESSAGE := RegisterWindowMessage('MSG_MY_UNIQUE_MESSAGE');end;{
      TMsgReceiver }constructor TMsgReceiver.Create;begin  inherited Create;  fMsgHandlerHWND := AllocateHWnd(WndMethod);  WM_MY_UNIQUE_MESSAGE := RegisterWindowMessage('MSG_MY_UNIQUE_MESSAGE');end;destructor TMsgReceiver.Destroy;begin  DeallocateHWnd(fMsgHandlerHWND);  inherited;end;procedure TMsgReceiver.WndMethod(var Msg: TMessage);begin  if Msg.Msg = WM_MY_UNIQUE_MESSAGE then  begin    Point.X := Msg.LParam;    Point.Y := Msg.WParam;    //just to receive some "output"    Windows.Beep(Point.X, Point.Y);  end  else    Msg.Result := DefWindowProc(fMsgHandlerHWND, Msg.Msg, Msg.wParam, Msg.lParam);end;procedure TClickSendForm.FormDestroy(Sender: TObject);begin  FreeAndNil(fMsgReceiver);end;procedure TClickSendForm.FormMouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);begin  PostMessage(HWND_BROADCAST, WM_MY_UNIQUE_MESSAGE, x, y);end;function TClickSendForm.GetMsgReceiver: TMsgReceiver;begin  if fMsgReceiver = nil then fMsgReceiver := TMsgReceiver.Create;  result := fMsgReceiver;end;end.