How to set width to 100% in WPF

Question

Is there any way how to tell component in WPF to take 100% of available space?

Like

width: 100%;  

in CSS

Answer 1

It is the container of the Grid that is imposing on its width. In this case, that's a ListBoxItem, which is left-aligned by default. You can set it to stretch as follows:

<ListBox>
    <!-- other XAML omitted, you just need to add the following bit -->
    <ListBox.ItemContainerStyle>
        <Style TargetType="ListBoxItem">
            <Setter Property="HorizontalAlignment" Value="Stretch"/>
        </Style>
    </ListBox.ItemContainerStyle>
</ListBox>

Answer 2

You could use HorizontalContentAlignment="Stretch" as follows:

<ListBox HorizontalContentAlignment="Stretch"/>