public void CreateAndRemoveOverlayWindow()
{
var app = new TestApp();
var window = app.CreateWindow() as IWindow;
app.LoadPage(new ContentPage());
var windowOverlay = new WindowOverlay(window) as IWindowOverlay;
// If not processed by a window, should be false.
Assert.False(windowOverlay.IsNativeViewInitialized);
// First time inserted, should be true.
Assert.True(window.AddOverlay(windowOverlay));
// Should now be initialized.
Assert.True(windowOverlay.IsNativeViewInitialized);
Assert.True(window.Overlays.Count > 0);
// Can't insert same window overlay again, should be false.
Assert.False(window.AddOverlay(windowOverlay));
// Should remove from collection, should be true.
Assert.True(window.RemoveOverlay(windowOverlay));
// Not in collection, should be false.
Assert.False(window.RemoveOverlay(windowOverlay));
// Window was uninitialized, should be false.
Assert.False(windowOverlay.IsNativeViewInitialized);
// Second time inserted, should be true.
Assert.True(window.AddOverlay(windowOverlay));
// Should now be initialized again.
Assert.True(windowOverlay.IsNativeViewInitialized);
}