WPF Application Layout - Make DockPanel fill space of ListBox - wpf

Question

I would like to make the "Cartoon" below to be aligned to the right and the yellow part to fill all the space in the middle of my ListBox item.
However, all I can get is this:
Here is my layout xaml:
<Window x:Class="Cartoons.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:sys="clr-namespace:System;assembly=mscorlib"
Title="Cartoons" Height="350" Width="525" SizeToContent="Width">
<DockPanel x:Name="mainPanel">
<Border Background="Green" DockPanel.Dock="Bottom" Width="Auto" Height="Auto">
<Grid Margin="2" Height="Auto">
<ListBox Name="listBoxCartoons" SelectionChanged="ListBox_SelectionChanged">
<ListBox.ItemTemplate>
<DataTemplate>
<DockPanel HorizontalAlignment="Stretch" Background="PowderBlue">
<DockPanel HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Background="AliceBlue" DockPanel.Dock="Left" >
<Image Source="<IMAGE_LOCATION>" Width="64" Height="64" Stretch="Fill"/>
</DockPanel>
<DockPanel HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Background="AliceBlue" DockPanel.Dock="Right">
<TextBlock Text="Cartoon" VerticalAlignment="Center"/>
</DockPanel>
<DockPanel HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Background="Yellow">
<StackPanel Orientation="Vertical" VerticalAlignment="Center">
<TextBlock Text="Character 1"/>
<TextBlock Text="Walt Disney"/>
<TextBlock Text="Speedy Gonzales"/>
</StackPanel>
</DockPanel>
</DockPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
</Border>
</DockPanel>
</Window>
I have tried many things but regardless what I do, it is alwasy displayed with large white space to the right.
Much appreciated,

Answer 1

If you're not avoiding hard-coding numbers in, such as margins, you could try this (tested in Visual Studio for your convenience):
<Border Background="Green" DockPanel.Dock="Bottom" Width="Auto" Height="Auto">
<Grid Margin="2" Height="Auto">
<ListBox Name="listBoxCartoons" SelectionChanged="ListBox_SelectionChanged">
<ListBoxItem>
<!-- Width of the below element may have to be adjusted -->
<Grid HorizontalAlignment="Stretch" Width="499">
<Image Source="<IMAGE_LOCATION>" Width="64" Height="64" Stretch="Fill" HorizontalAlignment="Left"/>
<!-- Margin of the below element may have to be adjusted -->
<StackPanel Orientation="Vertical" VerticalAlignment="Center" HorizontalAlignment="Stretch" Background="Yellow" Margin="69,8,0,8">
<TextBlock Text="Character 1"/>
<TextBlock Text="Walt Disney"/>
<TextBlock Text="Speedy Gonzales"/>
</StackPanel>
<Label Background="AliceBlue" Content="Cartoon" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" HorizontalAlignment="Right"/>
</Grid>
</ListBoxItem>
</ListBox>
</Grid>
</Border>
Also, there is an extra near the bottom of your XAML, above .

Answer 2

The problem is that the ListBox will generate container elements (of type ListBoxItem) for each item - these will, by default, align content to the left. To change that, add this to your ListBox:
<ListBox.ItemContainerStyle>
<Style TargetType="ListBoxItem">
<Setter Property="HorizontalContentAlignment" Value="Stretch"></Setter>
</Style>
</ListBox.ItemContainerStyle>

Answer 3

I figured it out.
Needed to set HorizontalContentAlignment="Stretch" on ListBox.
That resolved the issue. Just modify above line
<ListBox Name="listBoxCartoons" SelectionChanged="ListBox_SelectionChanged">
to
<ListBox Name="listBoxCartoons" HorizontalContentAlignment="Stretch" SelectionChanged="ListBox_SelectionChanged">
and it worked.