private void btnQuyen_Click(object sender, RoutedEventArgs e)
 {
     if (ucQuyen == null)
     {
         ucQuyen = new UserControlLibrary.UCQuyen(mTransit);
     }
     spNoiDung.Children.Clear();
     spNoiDung.Children.Add(ucQuyen);
 }
 private void btnQuyen_Click(object sender, RoutedEventArgs e)
 {
     if (ucQuyen == null)
     {
         ucQuyen = new UserControlLibrary.UCQuyen(mTransit);
     }
     spNoiDung.Children.Clear();
     spNoiDung.Children.Add(ucQuyen);
 }