UWP: how to get the RightTapped GridView Item
<p>I have a <code>GridView</code> like below</p>

<pre><code>&lt;GridView
         SelectionMode="None"
         IsItemClickEnabled="True"
         IsRightTapEnabled="True"
         ItemsSource="{x:Bind SymbolItems}"
         ItemClick="SymbolGridView_ItemClick"
         RightTapped="SymbolGridView_RightTapped"&gt;
   &lt;GridView.ItemTemplate&gt;
       &lt;DataTemplate x:DataType="data:SoundSymbolItem"&gt;
           &lt;local:SymbolControl/&gt;
       &lt;/DataTemplate&gt;
   &lt;/GridView.ItemTemplate&gt;
&lt;/GridView&gt;
</code></pre>

<p>I have a <code>ItemClick</code> handler and I can get the clicked <code>symbolItem</code> successfully</p>

<pre><code>    private void SymbolGridView_ItemClick(object sender, ItemClickEventArgs e)
    {
        var symbolItem = (SymbolItem)e.ClickedItem;
        MyMediaElement.Source = new Uri(this.BaseUri, symbolItem.SymbolAudio);
    }
</code></pre>

<p>Now, I want to do the similar thing for the <code>RightTapped</code> event, but it can't get the right tapped item.</p>

<pre><code>    private void SymbolGridView_RightTapped(object sender, RightTappedRoutedEventArgs e)
    {
        SymbolItem symbolItem = (sender as GridViewItem).DataContext as SymbolItem;
        MyMediaElement.Source = new Uri(this.BaseUri, symbolItem.ExampleAudio);
    }
</code></pre>

<p>I model the answer in this question <a href="https://stackoverflow.com/questions/32927743/get-righttapped-gridviewitem">Get RightTapped GridViewItem</a> to write my right tapped handler above, but it's not working. When I right click a gridview item, a NullReferenceException is triggered. </p>