Sometimes it handy to force the user’s attention to a specific screen. We can do this with a dialog, but sometimes the user doesn’t know that window is on top. To draw the user’s eye to the window, I like to place a backdrop between the rest of the application and the dialog window. I use the following code to make that happen.
1: public bool? ShowDialogWithBackdrop(Window win)
2: {
3: //create backgroup
4: Window backgroundWindow = new Window();
5: backgroundWindow.Top = 0;
6: backgroundWindow.Left = 0;
7: backgroundWindow.Height = SystemParameters.WorkArea.Height;
8: backgroundWindow.Width = SystemParameters.WorkArea.Width;
9: backgroundWindow.AllowsTransparency = true;
10: backgroundWindow.Background = Brushes.Transparent;
11: backgroundWindow.WindowStyle = WindowStyle.None;
12: backgroundWindow.ShowInTaskbar = false;
13: Rectangle rect = new Rectangle() { Fill = Brushes.Silver, Opacity = 0.5 };
14: backgroundWindow.Content = rect;
15: backgroundWindow.Show();
16: //set the owner so if the user clicks on the backdrop,
17: //the window will flash
18: win.Owner = backgroundWindow;
19: bool? rv = win.ShowDialog();
20: //dialog has returned. Close backdrop.
21: backgroundWindow.Close();
22: return rv;
23: }