private void Btn_joinRoom_Click(object sender, RoutedEventArgs e)
{
JoinRoomWindow wind = new JoinRoomWindow(this.username); //new JoinRoomWindow
wind.Show();
this.Hide();
}
private void JoinRoom_Click(object sender, RoutedEventArgs e)
{
this.isForcedClosing = false;
JoinRoomWindow jrw = new JoinRoomWindow(this.client);
this.Close();
jrw.Show();
}