I want to bind `AnswerList` in `QuestionList`. When I run code, only have question list on the screen.

```
<ListBox x:Name="listques"  ItemsSource="{Binding QuestionList  }">
    <ListBox.ItemTemplate>
       <DataTemplate>
          <StackPanel>
             <TextBlock x:Name="quesdetail"  Text="{Binding QuestionContent.que_detail}" HorizontalAlignment="Left" Margin="27.669,34.338,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Height="252.564" Width="419.534" RenderTransformOrigin="0.5,0.5" UseLayoutRounding="False" d:LayoutRounding="Auto">
       </TextBlock>
             <ListBox>
                <ListBox.ItemTemplate>
                   <DataTemplate>
                   <StackPanel>
                      <TextBlock x:Name="ansdetail" Foreground="Blue" Text="{Binding Answer.ans_detail}">
                       </TextBlock>
                   </StackPanel>
                   </DataTemplate>
                </ListBox.ItemTemplate>
             </ListBox>
          </StackPanel> 
       </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>

```