Height of ListBoxItem in VirtualizingStackPanel

Question

I'm developing an app where the entire UI is sized by percentage. Therefore the height of my ListBoxItems needs to be controlled by that too. But i'm having some problems getting it to work.

ListBoxStyle:

<Style x:Key="ListBoxStyle" TargetType="{x:Type ListBox}">
        <Setter Property="Stylus.IsPressAndHoldEnabled" Value="False" />
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type ListBox}">
                    <Border BorderBrush="{StaticResource ControlBorderBrush}" 
                            Background="{StaticResource ControlBackgroundBrush}">
                        <ScrollViewer ScrollViewer.VerticalScrollBarVisibility="Auto" ScrollViewer.HorizontalScrollBarVisibility="Disabled">
                            <VirtualizingStackPanel IsItemsHost="True" VirtualizingStackPanel.VirtualizationMode="Recycling">

                            </VirtualizingStackPanel>
                        </ScrollViewer>
                    </Border>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

ListBoxItemStyle:

<Style TargetType="{x:Type ListBoxItem}">
        <Setter Property="Stylus.IsPressAndHoldEnabled" Value="False" />
        <Setter Property="FocusVisualStyle" Value="{x:Null}" />
        <Setter Property="Foreground" Value="{StaticResource ControlTextNormalBrush}"/>
        <Setter Property="BorderThickness" Value="1,0,1,1"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="ListBoxItem">
                    <Border Name="Border"
                            Height="Height="{Binding Converter={StaticResource PercentageConverter}, Path=ActualHeight, ConverterParameter=10}""
                            SnapsToDevicePixels="true" 
                            BorderThickness="{TemplateBinding BorderThickness}" 
                            BorderBrush="{StaticResource ControlItemBorderBrush}" 
                            Background="{StaticResource ControlItemNormalBackgroundBrush}">

                        <ContentPresenter/>
                    </Border>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsMouseOver" Value="true">
                            <Setter TargetName="Border" Property="Background" Value="{StaticResource ControlItemHoverBackgroundBrush}"/>
                        </Trigger>
                        <Trigger Property="IsSelected" Value="true">
                            <Setter TargetName="Border" Property="Background" Value="{StaticResource ControlItemSelectedBackgroundBrush}" />
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
        <Style.Triggers>
            <Trigger Property="IsSelected" Value="true">
                <Setter Property="Foreground" Value="{StaticResource ControlTextSelectedBrush}"/>
            </Trigger>

            <DataTrigger Binding="{Binding RelativeSource={RelativeSource Self}, Converter= {StaticResource FirstItemConverter}}" Value="True">
                <Setter Property="BorderThickness" Value="1,1,1,1" />
            </DataTrigger>
        </Style.Triggers>
    </Style>

I have a PercentageConverter that i use other places to, it works like a charm. But it looks like in this scenario, that it is never called or does not have an effect. The height of the items is larger than the ListBox itself.

Answer 1

Using a UniformGrid as ItemsPanel for the ListBox will evenly space all items:

<ListBox>
    <ListBox.ItemsPanel>
        <ItemsPanelTemplate>
            <!-- Change to Rows="1" if you want a horizontal layout -->
            <UniformGrid Columns="1" />
        </ItemsPanelTemplate>
    </ListBox.ItemsPanel>
    <ListBox.Items>
        <ListBoxItem>Item 1</ListBoxItem>
        <ListBoxItem>Item 2</ListBoxItem>
        <ListBoxItem>Item 3</ListBoxItem>
        <ListBoxItem>Item 4</ListBoxItem>
        <ListBoxItem>Item 5</ListBoxItem>
        <ListBoxItem>Item 6</ListBoxItem>
        <ListBoxItem>Item 7</ListBoxItem>
        <ListBoxItem>Item 8</ListBoxItem>
    </ListBox.Items>
</ListBox>

Now 8 items will each have 12.5% height (1/8) and 100% width (1/1). This page explains the workings of a UniformGrid.