Very often you need to stretch your ListBoxItem horizontally. If the ListBox is simple (without ItemTemplate), there is easy solution: just add
to the ListBox.
However, in second way the solution is easy too. But frequently we spend a lot of time to fix it. There is a solution:
<ListBox.ItemContainerStyle> <Style TargetType=”ListBoxItem”> <Setter Property=”HorizontalContentAlignment” Value=”Stretch”></Setter> </Style> </ListBox.ItemContainerStyle>