Silverlight pop up window [4.0]

Please add this code on click event :

 private void dataGrid1_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {

            Popup p;
            // Create a popup.
            p = new Popup();

            // Set the Child property of Popup to an instance of MyControl.
            p.Child = new Views.SilverlightControl1();

            // Set where the popup will show up on the screen.
            p.VerticalOffset = 600;
            p.HorizontalOffset = 600;

            // Open the popup.
            p.IsOpen = true;


            //MessageBox.Show(dataGrid1.CurrentColumn.Header.ToString() + ": " +
            //        ((TextBlock)dataGrid1.CurrentColumn.GetCellContent(dataGrid1.SelectedItem)).Text);

        }

//------------------------------
  private void CloseBtn_Click(object sender, RoutedEventArgs e)
        {
            this.Visibility = Visibility.Collapsed;
        }