How to get a ListBox ItemTemplate to stretch horizontally the full width of the ListBox?

I found another solution here, since I ran into both post…

This is from the Myles answer:

<ListBox.ItemContainerStyle> 
    <Style TargetType="ListBoxItem"> 
        <Setter Property="HorizontalContentAlignment" Value="Stretch"></Setter> 
    </Style> 
</ListBox.ItemContainerStyle> 

This worked for me.