procedure TForm1.Button1Click(Sender: TObject);
begin
if not assigned(Form2) then
begin
Form2 := TForm2.Create(self);
Form2.Parent := panel1;
Form2.WindowState := wsMaximized;
Form2.Color := clRed;
Form2.BorderStyle := bsNone;
Form2.Show;
end
else
begin
Form2.Close;
Form2 := nil;
end;
end;