title: How to change the image on the ApplicationBar from C#?
body: <p>I have a small C# project that has an ApplicationBar. But I have a small problem: I want 8 icons on the bar, and the ApplicationBar only supports 4. I came up with a solution (in C#): add a small CheckBox to ask if the user wants to use the first or second set of tools.<p>But I'm still not able to change the icons on the ApplicationBar. I tried removing the old ones, first with <code>ApplicationBar.MenuItems.Remove(Button1);</code> and then with <code>ApplicationBar.Buttons.Remove(Button1);
  </code> but neither worked. I tried changing the <code>.IconUri</code> property of the button, but that gave me a NullReferenceException.</p>