XAML element inside of ItemsControl DataTemplate sometimes has null parent (WinRT) - xaml

Question

I'm making a win8 app. I have an ItemsControl with a DataTemplate. Inside this DataTemplate, there is a Grid. Inside this Grid there is a WebView and a ProgressRing. I have an event for LoadCompleted on the WebView, at which time I want to disable the ProgressRing. My thought was to use the following:
ProgressRing pr = ((sender as FrameworkElement).Parent as Grid).Children.First(t => t.GetType().Equals(typeof(ProgressRing))) as ProgressRing;
pr.IsActive = false;
And this works sometimes, but sometimes it claims that ((sender as FrameworkElement).Parent) is null. I verified from debugging that in these cases, the sender is still the correct WebView. The WebView is being shown on the screen and is formatted correctly - so how could its parent be null?
Here's the XAML:
<ItemsControl Margin="40,0,40,0" x:Name="resultsItemsControl">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"></StackPanel>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid Margin="50,0">
<Grid.RowDefinitions>
<RowDefinition Height="auto"></RowDefinition>
<RowDefinition Height="*"></RowDefinition>
<RowDefinition Height="30"></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="150" MaxWidth="150"></ColumnDefinition>
<ColumnDefinition Width="auto"></ColumnDefinition>
<ColumnDefinition Width="100" MaxWidth="100"></ColumnDefinition>
<ColumnDefinition Width="*"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Button Grid.Column="0" x:Name="viewInBrowser" IsEnabled="False" Style="{StaticResource PreviewLinkAppBarButtonStyle}" Margin="0,0,40,0" Click="viewInBrowser_Click_1"></Button>
<TextBlock HorizontalAlignment="Left" TextAlignment="Left" Grid.Column="1" FontSize="30" Margin="0,20,0,20" FontWeight="Bold" FontFamily="Georgia" VerticalAlignment="Center" Text="{Binding Name}"></TextBlock>
<ProgressRing x:Name="loadingProgressRing" Margin="20,0" Grid.Column="2" Foreground="White" IsActive="True" HorizontalAlignment="Left" VerticalAlignment="Center"></ProgressRing>
<WebView ScriptNotify="WebView_ScriptNotify_1" Grid.Column="0" Grid.ColumnSpan="14" Grid.Row="1" Source="{Binding CurrentSearchUrl}" Width="0" LoadCompleted="WebView_LoadCompleted_1"></WebView>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>

Answer 1

I wouldn't use a WebView in an ItemsControl at all, but you could try putting your entire template in a UserControlm then you handle the event inside of the UserControl and don't need to care about sender, since you can just name the Grid and access a named Grid.