VirtualizingStackPanel.VirtualizationMode Attached Property

By default, a VirtualizingStackPanel creates an item container for each visible item and discards it when it is no longer needed (such as when the item is scrolled out of view). When an ItemsControl contains a lot of items, the process of creating and discarding item containers can negatively affect performance. When VirtualizingStackPanel.VirtualizationMode is set to Recycling, the VirtualizingStackPanel reuses item containers instead of creating a new one each time.

The following example creates a ListBox and sets the VirtualizingStackPanel.VirtualizationMode attached property to Recycling.

<StackPanel>

  <StackPanel.Resources>
    <src:LotsOfItems x:Key="data"/>
  </StackPanel.Resources>

  <ListBox Height="150" ItemsSource="{StaticResource data}" 
             VirtualizingStackPanel.VirtualizationMode="Recycling" />

</StackPanel>

The following example shows the data used in the previous example.

public class LotsOfItems : ObservableCollection<String>
{
    public LotsOfItems()
    {
        for (int i = 0; i < 1000; ++i)
        {
            Add("item " + i.ToString());
        }
    }
}

.NET Framework

.NET Framework Client Profile

Windows 8 Consumer Preview, Windows Server 8 Beta, Windows 7, Windows Server 2008 SP2, Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

Reference