Change listbox template on lost focus event in WPF - wpf

Question

I want to present a listbox with TextBlocks as items. When the user clicks/selects an item it changes into a TextBox for editing. As soon as the controls loses focus the item would turn back to a TextBlock.
The following XAML is almost working in that the TextBlock does turn into a TextBox when it's selected. It also turns back to a TextBlock if I select another item on the list. The problem is that if I move out of the listbox (in this case to the Add New text box) the list item stays as a TextBox.
The question ( WPF ListViewItem lost focus event - How to get at the event? ) looked promising but I can't make it work. I tried using the IsFocused property but then I wasn't able to edit the textbox because when I got into the textbox the listboxitem would go out of focus and thus turning back to a TextBlock before I had a chance to edit the text.
How can I make the TextBox turn back to TextBlock if the listbox/item loses the focus?
(Any other implementation that accomplishes the goal are also welcomed)
<Window x:Class="MyView.MainWindow1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
Title="MainWindow1" Height="300" Width="200">
<Window.Resources>
<DataTemplate x:Key="ItemTemplate">
<TextBlock Text="{Binding Name}" />
</DataTemplate>
<DataTemplate x:Key="SelectedTemplate">
<TextBox Text="{Binding Name, Mode=TwoWay}" />
</DataTemplate>
<Style TargetType="{x:Type ListBoxItem}" x:Key="ContainerStyle">
<Setter Property="ContentTemplate" Value="{StaticResource ItemTemplate}" />
<Style.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter Property="ContentTemplate" Value="{StaticResource SelectedTemplate}" />
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
<StackPanel >
<ListBox ItemsSource="{Binding Departments}" HorizontalContentAlignment="Stretch"
ItemContainerStyle="{StaticResource ContainerStyle}" />
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<TextBox Text="{Binding NewDepartmentName, Mode=TwoWay}" />
<Button Grid.Column="1" Width="50" Content="Add" Command="{Binding Path=AddNewDepartmentCommand}" />
</Grid>
</StackPanel>
</Window>

Answer 1

This doesn't answer your question, but gives an alternative solution by making a textbox look like a textblock when the listboxitem isn't selected:
<Page.Resources>
<ResourceDictionary>
<Style x:Key="ListBoxSelectableTextBox" TargetType="{x:Type TextBox}">
<Setter Property="IsHitTestVisible" Value="False" />
<Style.Triggers>
<DataTrigger Binding="{Binding IsSelected, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBoxItem}, AncestorLevel=1}}" Value="True">
<Setter Property="IsHitTestVisible" Value="True" />
</DataTrigger>
</Style.Triggers>
</Style>
</ResourceDictionary>
</Page.Resources>
<Grid>
<ListBox ItemsSource="{Binding Departments}" HorizontalContentAlignment="Stretch">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBox Margin="5" Style="{StaticResource ListBoxSelectableTextBox}" Text="{Binding Name}" BorderBrush="{x:Null}"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>

Answer 2

There are many ways you can do this:
Above answer
Create a TextBox style based on TextBoxBase such that when disabled, it makes the TextBox look like a TextBlock by setting the BorderThickness="0", Background="transparent"
Have both TextBlock and TextBox on each ListViewItem and using the above answer technique hide and show the TextBlock/TextBox accrodingly