How to set background image in Windows Phone 8?

Question

I am very new to WP apps and don\'t know how to set the back-ground image in app.xaml file for whole application in Windows Phone 8<

Answer 1

I use the following in the InitializePhoneApplication method of my app.xaml.cs. The effect is that every page has the same background image, and there's no flashing/blanking upon page navigation

 RootFrame = new PhoneApplicationFrame
 {
    Background = new ImageBrush()
    {
       ImageSource = new BitmapImage(new Uri("Assets/Russel_Logo_ep2s.png", UriKind.Relative)),
       Opacity = 0.3,
       Stretch = System.Windows.Media.Stretch.None,
       AlignmentX = AlignmentX.Center,
       AlignmentY = AlignmentY.Center
    }
 };