String returning null - windows-phone-8.1

Question

I am facing issues getting the string values using e.ClickedItem.
Here's how my ListView looks like:
<ListView
x:Name="PoemListView"
AutomationProperties.AutomationId="PoemListView"
AutomationProperties.Name="Poems In Item"
TabIndex="1"
ItemsSource="{Binding Item.Poems}"
IsItemClickEnabled="True"
ItemClick="PoemView_PoemClick"
SelectionMode="None"
SelectionChanged="PoemSelectionChanged"
IsSwipeEnabled="False" Padding="0,0,0,0" Margin="0,0,0,0"
ContinuumNavigationTransitionInfo.ExitElementContainer="True">
<ListView.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<StackPanel Grid.Column="1" VerticalAlignment="Top" Margin="0,0,0,27.5" HorizontalAlignment="Left" ScrollViewer.VerticalScrollBarVisibility="Hidden">
<!--<CheckBox x:Name="PoemCheckbox" Checked="ContentChecked" Unchecked="ContentUnchecked"/>-->
<TextBlock x:Uid="PoemId" Name="PoemId" Text="{Binding PoemId}" DataContext="{Binding}" Style="{ThemeResource ListViewItemSubheaderTextBlockStyle}" TextWrapping="WrapWholeWords"/>
<TextBlock x:Uid="PoemTitleId" Text="{Binding PoemTitle}" FontSize="{Binding ElementName=FontSlider, Mode=OneWay, Path=Value}" DataContext="{Binding}" Style="{ThemeResource ListViewItemSubheaderTextBlockStyle}" Foreground="{ThemeResource PhoneMidBrush}" TextWrapping="WrapWholeWords"/>
<TextBlock x:Uid="PoemMeanId" Text="{Binding PoemMean}" DataContext="{Binding}" Style="{ThemeResource ListViewItemSubheaderTextBlockStyle}" TextWrapping="WrapWholeWords"/>
</StackPanel>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
This is the code behind the xaml page:
private void PoemView_PoemClick(object sender, ItemClickEventArgs e)
{
TextBlock PoemId = e.ClickedItem as TextBlock;
this.Frame.Navigate(typeof(Favorite), (e.ClickedItem as TextBlock));
On LoadState event of the Favorite page, I have added the below code:
private void NavigationHelper_LoadState(object sender, LoadStateEventArgs e)
{
string poem = e.NavigationParameter as string;
if (string.IsNullOrEmpty(poem))
{
FavText.Text = "no favorite text";
}
else { FavText.Text = poem;
}
}
The problem is in the LoadState while the e.NavigationParameter is loaded with the strings passed to it, the string poem is not loading properly. Therefore, the FavText.Text is always returning the "no favorite text".
Anyone has a clue on how to fix this?

Answer 1

Your PoemId is probably null when you cast e.ClickedItem as TextBlock
Try this
Poem poem = e.ClickedItem as Poem;
this.Frame.Navigate(typeof(Favorite), poem);

Answer 2

Instead of casting e.ClickedItem as TextBlock, I updated the code as below which worked perfectly fine:
var type = ((PoemItem)e.ClickedItem).PoemTitle;
this.Frame.Navigate(typeof(Favorite), type);