Question

I have a listview:

<ListView Name="SelectedFeeds">
    <ListView.ItemContainerStyle>
        <Style TargetType="{x:Type ListViewItem}" 
               BasedOn="{StaticResource {x:Type ListViewItem}}">
            <Style.Triggers>
                 <Trigger Property="IsSelected" Value="True">

                 </Trigger>
            </Style.Triggers>
        </Style>
    </ListView.ItemContainerStyle>
    <ListView.ItemTemplate>
        <DataTemplate>
            <StackPanel Orientation="Vertical" Name="panel">
                <TextBlock x:Name="Title" FontSize="24" 
                           Text="{Binding Title, IsAsync=True}" TextWrapping="Wrap" />
                        <Label x:Name="PubDate" FontSize="10" 
                               Content="{Binding Path=PubDate, IsAsync=True}" />
                        <TextBlock my:HtmlParser.HTMLText=
                                   "{Binding Path=Description, IsAsync=True}" 
                                   TextWrapping="Wrap" 
                                   Width="{Binding ElementName=panel, 
                                   Path=ActualWidth}" Height="0" />
             </StackPanel>
        </DataTemplate>
    </ListView.ItemTemplate>
</ListView>

There is a TextBlock in DataTemplate with large height.

At start I’m setting height of this textblock to “0” and when ListViewItem is selected, I need to set that height to “Auto”.

This is probably can be done with triggers, but I can’t figure it out.

Answer 1

For a trigger approach, use it in the DataTemplate.

<ListView Name="SelectedFeeds">
    <ListView.ItemTemplate>
        <DataTemplate>
            <StackPanel Orientation="Vertical" Name="panel">
                <TextBlock x:Name="Title" FontSize="24" 
                           Text="{Binding Title, IsAsync=True}" TextWrapping="Wrap" />
                        <Label x:Name="PubDate" FontSize="10" 
                               Content="{Binding Path=PubDate, IsAsync=True}" />
                        <TextBlock x:Name="TextHolder"
                                   my:HtmlParser.HTMLText=
                                   "{Binding Path=Description, IsAsync=True}" 
                                   TextWrapping="Wrap" 
                                   Width="{Binding ElementName=panel, 
                                   Path=ActualWidth}" Height="0" />
             </StackPanel>
            <DataTemplate.Triggers>
                <DataTrigger Binding="{Binding IsSelected, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListViewItem}}}" Value="True">
                    <Setter TargetName="TextHolder" Property="Height" Value="123"/>
                </DataTrigger>
            </DataTemplate.Triggers>
        </DataTemplate>
    </ListView.ItemTemplate>
</ListView>

Note the x:Name property on the TextBlock.