Horizontal Scrollbars on a Fluid Listbox

What I want: To get the darn horizontal scrollbar to appear. I will be editing it a bit just so i fits the rest of the app's style scheme, but not too much.

What I have

Here is the code for the listbox as of now. Everything runs perfectly except the scrollbars do开发者_如何学运维nt appear. You might say... "well you dont have a scrollviewer anywhere", but I have tried inserting a scrollviewer in numerous places and still no luck.

The Listbox Code:

<ListBox ItemsSource="{Binding Items}" ItemTemplate="{StaticResource itemsdatatemplate}" Background="{x:Null}" BorderBrush="{x:Null}" Foreground="{x:Null}" ItemsPanel="{StaticResource HorizontalListBoxTemplate}" ItemContainerStyle="{StaticResource TransparentListBox}" VerticalAlignment="Center" SelectedItem="{Binding SelectedItem, Mode=TwoWay}" />

The 'TransparentListBox' (to shut-up the selected background color):

<Style x:Key="TransparentListBox" TargetType="ListBoxItem">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="ListBoxItem">
                <Grid>
                    <Border x:Name="HoverBorderBackgroundBrush" BorderThickness="1" Margin="0,0,25,0" Background="Transparent"/>
                    <Border x:Name="SelectedBorderBackgroundBrush" BorderThickness="1" Margin="0,0,25,0" Background="Transparent"/>
                        <ContentPresenter></ContentPresenter>
                </Grid>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

Horizontal List Box (to make the listbox Horizontal, rather than standard vertical)

<ItemsPanelTemplate x:Key="HorizontalListBoxTemplate">
    <StackPanel Orientation="Horizontal">
    </StackPanel>
</ItemsPanelTemplate>

The Datatemplate (to actually show the Items)

<DataTemplate x:Key="itemsdatatemplate">
        <local:ListItemControl HorizontalAlignment="Left" VerticalAlignment="Top" DataContext="{Binding}"/>
</DataTemplate>

I have a feeling its going to be a simple addition, but Thanks in advance.

Update

It looks like the scrollbars now do appear with this:

    <Style x:Key="ScrollingListBox" TargetType="ListBox">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate>
                    <Grid>
                        <ScrollViewer HorizontalScrollBarVisibility="Visible">
                            <ItemsPresenter></ItemsPresenter>
                        </ScrollViewer>
                    </Grid>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

But they do not function accordingly. They feel... broken. However, if one was to define a static width (say 300) of the grid, then the ScrollViewer acts perfectly. Right now I have a completely fluid layout (meaning things stretch to fill), is this not acceptable for scrollviewers?

---

When you create your own template, you have to define the ScrollViewer in there and use an ItemPresenter instead of a ContentPresenter.

<Style x:Key="TransparentListBox" TargetType="ListBoxItem">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="ListBoxItem">
                <Grid>
                    <Border x:Name="HoverBorderBackgroundBrush" BorderThickness="1" Margin="0,0,25,0" Background="Transparent"/>
                    <Border x:Name="SelectedBorderBackgroundBrush" BorderThickness="1" Margin="0,0,25,0" Background="Transparent"/>
                        <ScrollViewer x:Name="ScrollViewer" HorizontalScrollBarVisibility="Visible">
                            <ItemsPresenter />
                        </ScrollViewer>
                </Grid>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>