procedure TForm1.miClick(Sender: TObject);
begin
        ShowMessage('El nuevo boton ha sido pulsado');
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
        with TButton.Create(self) do begin
                Left := 50;
                Top := 50;
                Width := 120;
                Height := 40;
                Name := 'Boton nuevo';
                Caption := 'Un boton';
                OnClick :=  miClick;
                Parent := Form1;
        end;
end;