Stretch ListBox Items hit area to full width of the ListBox? ListBox style is set implicity through a theme

Question

I\'ve looked around for an answer on this, but the potential duplicates are more concerned with presentation than interaction.

I have a basic list box, and each ite

Answer 1

HorizontalContentAlignment="Stretch" should be set in ItemContainerStyle for this to work.

Xaml Example

<ListBox xmlns:sys="clr-namespace:System;assembly=mscorlib">
    <ListBox.ItemsSource>
        <x:Array Type="{x:Type sys:String}">
            <sys:String>String 1</sys:String>
            <sys:String>String 2</sys:String>
            <sys:String>String 3</sys:String>
            <sys:String>String 4</sys:String>
        </x:Array>
    </ListBox.ItemsSource>
    <ListBox.ItemContainerStyle>
        <Style TargetType="ListBoxItem">
            <Setter Property="HorizontalContentAlignment" Value="Stretch" />
        </Style>
    </ListBox.ItemContainerStyle>
    <ListBox.ItemTemplate>
        <DataTemplate>
            <TextBlock Text="{Binding}" Background="Green"/>
        </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>

Update
Try this

<ListBox ...>
    <ListBox.ItemContainerStyle>
        <Style TargetType="ListBoxItem" BasedOn="{StaticResource {x:Type ListBoxItem}}">
            <Setter Property="HorizontalContentAlignment" Value="Stretch" />
        </Style>
    </ListBox.ItemContainerStyle>

Answer 2

Also, adding to Fredrik's answer, if you set the ListBox's ScrollViewer.HorizontalScrollBarVisibility property to Disabled, the items will always have exactly the client width of the ListBox.