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I recently needed to put some items inside a WrapPanel in WPF, which I wanted to scroll vertically if there were too many items to fit into the available space. I was undecided on whether I wanted to use an ItemsControl or a ListView (which adds selected item capabilities), and discovered that when you switch between the two containers, the technique for getting the WrapPanel working is subtly different.

ItemsControl is the simplest. Just set the ItemsPanelTemplate to be a WrapPanel, and then put the whole thing inside a ScrollViewer (sadly you can’t put the ScrollViewer inside the ItemsPanelTemplate):

<ScrollViewer>    
  <ItemsControl>
    <ItemsControl.ItemsPanel>
      <ItemsPanelTemplate>
        <WrapPanel />
      </ItemsPanelTemplate>
    </ItemsControl.ItemsPanel>
    <Rectangle Margin="5" Width="100" Height="100" Fill="Beige" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="PowderBlue" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FF9ACD32" />    
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFFF6347" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FF6495ED" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFFFA500" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFFFD700" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFFF4500" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FF316915" />    
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FF8E32A7" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFECBADC" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFE6D84F" />
  </ItemsControl>
</ScrollViewer>

this produces the following results:

image

But if you switch to an ItemsView instead, you’ll find that you get a single row of items with a horizontal scrollbar while the outer ScrollViewer has nothing to do.

image

The solution is to disable the horizontal scrollbar of the ListView itself:

<ListView ScrollViewer.HorizontalScrollBarVisibility="Disabled">

This allows our top-level ScrollViewer to work as with the ItemsControl and we have selection capabilities as well:

image

The full XAML for the ListView with vertically scrolling WrapPanel is:

<ScrollViewer>    
  <ListView ScrollViewer.HorizontalScrollBarVisibility="Disabled">
    <ListView.ItemsPanel>
      <ItemsPanelTemplate>
        <WrapPanel />
      </ItemsPanelTemplate>
    </ListView.ItemsPanel>
    <Rectangle Margin="5" Width="100" Height="100" Fill="Beige" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="PowderBlue" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FF9ACD32" />    
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFFF6347" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FF6495ED" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFFFA500" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFFFD700" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFFF4500" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FF316915" />    
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FF8E32A7" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFECBADC" />
    <Rectangle Margin="5" Width="100" Height="100" Fill="#FFE6D84F" />
  </ListView>
</ScrollViewer>
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