Handle messages without forms?

Want to handle messages without creating an actual form? Send messages between a thread and your main app? Or just impress your friends by using messages to communicate between forms? This is a very handy class that i’ve used over the years. Just override “HandleMessage” to intercept and process your own messages (ps: dispatch is your friend).

  TMessageHandler = Class(TObject)
  private
    FHandle:    HWND;
  protected
    Property    Handle:HWND read FHandle;
    Procedure   HandleMessage(var message:TMessage);virtual;
  public
    Constructor Create;virtual;
    Destructor  Destroy;Override;
  End;

constructor TMessageHandler.Create;
begin
  inherited Create;
  FHandle:=AllocateHWnd(HandleMessage);
end;

destructor TMessageHandler.Destroy;
begin
  DeallocateHWnd(FHandle);
  inherited;
end;

procedure TMessageHandler.HandleMessage(var Message:TMessage);
begin
  Message.Result := DefWindowProc(FHandle, Message.Msg,
  Message.wParam, Message.lParam);
end;