75
votes

In the following WPF XAML the ScrollViewer does not work (it displays a scroll bar but you cannot scroll and the contents go off the window to the bottom).

I can change the outer StackPanel to a Grid and it will work.

However, in my application from which I reproduced the following code, I need to have an outer StackPanel. What do I have to do to the StackPanel to make the ScrollViewer show a usable scrollbar? e.g. VerticalAlignment="Stretch" Height="Auto" don't work.

 <StackPanel>
        <ScrollViewer>
            <StackPanel>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
                <TextBlock Text="This is a test"/>
            </StackPanel>
        </ScrollViewer>
 </StackPanel>
7

7 Answers

59
votes

You can't without fixing the height of the StackPanel. It's designed to grow indefinitely in one direction. I'd advise using a different Panel. Why do you "need" to have an outer StackPanel?

59
votes

This was bugging me for a while too, the trick is to put your stackpanel within a scrollviewer.

Also, you need to ensure that you set the CanContentScroll property of the scroll viewer to True, here's an example:

  <ScrollViewer Grid.Row="1" Margin="299,12,34,54" Name="ScrollViewer1" VerticalScrollBarVisibility="Auto" HorizontalScrollBarVisibility="Auto" Height="195" CanContentScroll="True">
        <StackPanel Name="StackPanel1" OverridesDefaultStyle="False"  Height="193" Width="376" VerticalAlignment="Top" HorizontalAlignment="Left"></StackPanel>
  </ScrollViewer>
8
votes

Notice that sometimes you might have a StackPanel without realizing it. In my case I had this code

<ScrollViewer>
  <ItemsControl ItemsSource="{Binding Pages}"/>
</ScrollViewer>

which worked fine. The "Pages" referenced by the binding was really different, complex UserControls, and I wanted to have only scrollbars on some of them. So I removed the scrollviewer:

 <ItemsControl ItemsSource="{Binding Pages}"/>

And then I put the ScrollViewer as the top element on those of the usercontrols where I wanted them. However, this did not work. The content just flowed off the page. At first i didn't think this question/answer could help me, but the I realized that the default ItemPanel of an ItemsControl is the StackPanel. So I solved my problem by specifying an ItemsPanel that was not the StackPanel:

<ItemsControl ItemsSource="{Binding Pages}">
    <ItemsControl.ItemsPanel>
        <ItemsPanelTemplate>
            <Grid/>
        </ItemsPanelTemplate>
    </ItemsControl.ItemsPanel>
</ItemsControl>
5
votes

This is how it works:

<Window x:Class="TabControl.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"        
    xmlns:local="clr-namespace:TabControl"
    Title="MainWindow"    Height="300"   
    DataContext="{Binding RelativeSource={RelativeSource Self}}"         
    >    
<StackPanel>
    <ScrollViewer Height="{Binding RelativeSource={RelativeSource Mode=FindAncestor,AncestorType={x:Type Border}},Path=ActualHeight}" >
        <StackPanel >
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
            <TextBlock Text="This is a test"/>                <TextBlock Text="This is a test"/>
        </StackPanel>
    </ScrollViewer>
</StackPanel>

By binding the ScrollViewer's Height to Window's Inner Height.

The logic of re-sizing is we need to give any element fix height or design the view to use render height.

Output:

Scrollbar in Stackpanel

4
votes

Indeed, the way I solved that dileman was to remove the outer stack panel and instead set the scrollviewer in the position I wanted inside the main grid.

        <Grid Style="{StaticResource LayoutRootStyle}">
    <Grid.RowDefinitions>
        <RowDefinition Height="160"/>
        <RowDefinition Height="*"/>
    </Grid.RowDefinitions>        

    <!-- Vertical scrolling grid used in most view states -->    

        <ScrollViewer Grid.Row="1" HorizontalScrollBarVisibility="Auto">
            <StackPanel Orientation="Horizontal">
                <GridView>
                ...
                </GridView>
            </StackPanel>
        </ScrollViewer>        
2
votes

Here's how I would do it if your stack panel is inside a grid:

<ScrollViewer Grid.Row="1" VerticalScrollBarVisibility="Auto">
    <StackPanel MaxHeight="{Binding Path=Height,RelativeSource={RelativeSource 
              AncestorType=Grid}}">
    </StackPanel>
</ScrollViewer>
1
votes

Moving Grid.Row="1" from StackPanel to ScrollViewer completely solved it for me.

I had a long list of some 40 items to show in a StackPanel, but only the first 20 were showing.

    <ScrollViewer Grid.Row="1" VerticalScrollBarVisibility="Auto">
        <StackPanel x:Name="ContentPanel" Margin="12,0,12,0">
        <TextBlock Text="{Binding Line1}" Margin="9,-7,0,0" Style="{StaticResource PhoneTextTitle1Style}"/>
        <TextBlock Text="" Margin="10,-2,10,0" Style="{StaticResource PhoneTextNormalStyle}" />
        ...
        </StackPanel>
    </ScrollViewer>