HierarchicalVirtualizationItemDesiredSizes.LogicalSizeBeforeViewport Property        
Definition
Important
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Gets the control's child items that are in the cache before the viewport, in logical units.
public:
 property System::Windows::Size LogicalSizeBeforeViewport { System::Windows::Size get(); };
	public System.Windows.Size LogicalSizeBeforeViewport { get; }
	member this.LogicalSizeBeforeViewport : System.Windows.Size
	Public ReadOnly Property LogicalSizeBeforeViewport As Size
	Property Value
The control's child items that are in the cache before the viewport, in logical units.