How to set width to 100% in WPF <p>Is there any way how to tell component in <strong>WPF</strong> to take 100% of available space? </p> <p>Like </p> <pre><code>width: 100%; </code></pre> <p>in CSS </p> <p>I've got this XAML, and I don't know how to force Grid to take 100% width.</p> <pre><code>&lt;ListBox Name="lstConnections"&gt; &lt;ListBox.ItemTemplate&gt; &lt;DataTemplate&gt; &lt;Grid Background="LightPink"&gt; &lt;Grid.ColumnDefinitions&gt; &lt;ColumnDefinition Width="Auto"/&gt; &lt;ColumnDefinition Width="Auto"/&gt; &lt;/Grid.ColumnDefinitions&gt; &lt;Grid.RowDefinitions&gt; &lt;RowDefinition Height="Auto"/&gt; &lt;RowDefinition Height="Auto"/&gt; &lt;/Grid.RowDefinitions&gt; &lt;TextBlock Grid.Row="0" Grid.Column="0" Text="{Binding Path=User}" Margin="4"&gt;&lt;/TextBlock&gt; &lt;TextBlock Grid.Row="0" Grid.Column="1" Text="{Binding Path=Password}" Margin="4"&gt;&lt;/TextBlock&gt; &lt;TextBlock Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2" Text="{Binding Path=Host}" Margin="4"&gt;&lt;/TextBlock&gt; &lt;/Grid&gt; &lt;/DataTemplate&gt; &lt;/ListBox.ItemTemplate&gt; &lt;/ListBox&gt; </code></pre> <p>Result looks like </p> <p><img src="http://foto.darth.cz/pictures/wpf_width.jpg" alt="alt text"></p> <p>I made it pink so it's obvious how much space does it take. I need to make the pink grid 100% width.</p>