VirtualizingLayout Class

Definition

Namespace:

Microsoft.UI.Xaml.Controls

Represents the base class for an object that sizes and arranges child elements for a host and supports virtualization.

This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces).

/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
/// [Windows.Foundation.Metadata.ContractVersion(Microsoft.UI.Xaml.XamlContract, 65536)]
class VirtualizingLayout : Layout

[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
[Windows.Foundation.Metadata.ContractVersion(typeof(Microsoft.UI.Xaml.XamlContract), 65536)]
public class VirtualizingLayout : Layout

Public Class VirtualizingLayout
Inherits Layout

Inheritance

DependencyObject

Layout

VirtualizingLayout

Derived

Microsoft.UI.Xaml.Controls.FlowLayout

Microsoft.UI.Xaml.Controls.StackLayout

Microsoft.UI.Xaml.Controls.UniformGridLayout

Attributes

MarshalingBehaviorAttribute ThreadingAttribute ContractVersionAttribute

Examples

Tip

For more info, design guidance, and code examples, see Layout.

The WinUI 3 Gallery and WinUI 2 Gallery apps include interactive examples of most WinUI 3 and WinUI 2 controls, features, and functionality.

If installed already, open them by clicking the following links: WinUI 3 Gallery or WinUI 2 Gallery.

If they are not installed, you can download the WinUI 3 Gallery and the WinUI 2 Gallery from the Microsoft Store.

You can also get the source code for both from GitHub (use the main branch for WinUI 3 and the winui2 branch for WinUI 2).

Remarks

VirtualizingLayout is the base class for layouts that support virtualization. You can use one of the provided derived class, or inherit from it to create your own layout. Provided concrete virtualizing layout classes are StackLayout, and UniformGridLayout.

Constructors

VirtualizingLayout()

Initializes a new instance of the VirtualizingLayout class. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces).

Methods

Arrange(LayoutContext, Size)	Positions child elements and determines a size for a container UIElement. Container elements that support attached layouts should call this method from their layout override implementations to form a recursive layout update. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces). (Inherited from Layout)
ArrangeOverride(VirtualizingLayoutContext, Size)	When implemented in a derived class, provides the behavior for the "Arrange" pass of layout. Classes can override this method to define their own "Arrange" pass behavior. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces).
InitializeForContext(LayoutContext)	Initializes any per-container state the layout requires when it is attached to a UIElement container. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces). (Inherited from Layout)
InitializeForContextCore(VirtualizingLayoutContext)	When overridden in a derived class, initializes any per-container state the layout requires when it is attached to a UIElement container. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces).
InvalidateArrange()	Invalidates the arrange state (layout) for all UIElement containers that reference this layout. After the invalidation, the UIElement will have its layout updated, which occurs asynchronously. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces). (Inherited from Layout)
InvalidateMeasure()	Invalidates the measurement state (layout) for all UIElement containers that reference this layout. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces). (Inherited from Layout)
Measure(LayoutContext, Size)	Suggests a DesiredSize for a container element. A container element that supports attached layouts should call this method from their own MeasureOverride implementations to form a recursive layout update. The attached layout is expected to call the Measure for each of the container’s UIElement children. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces). (Inherited from Layout)
MeasureOverride(VirtualizingLayoutContext, Size)	Provides the behavior for the "Measure" pass of the layout cycle. Classes can override this method to define their own "Measure" pass behavior. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces).
OnItemsChangedCore(VirtualizingLayoutContext, Object, NotifyCollectionChangedEventArgs)	Notifies the layout when the data collection assigned to the container element (ItemsSource) has changed. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces).
UninitializeForContext(LayoutContext)	Removes any state the layout previously stored on the UIElement container. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces). (Inherited from Layout)
UninitializeForContextCore(VirtualizingLayoutContext)	When overridden in a derived class, removes any state the layout previously stored on the UIElement container. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces).

Events

ArrangeInvalidated	Occurs when the arrange state (layout) has been invalidated. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces). (Inherited from Layout)
MeasureInvalidated	Occurs when the measurement state (layout) has been invalidated. This documentation applies to WinUI 2 for UWP (for WinUI in the Windows App SDK, see the Windows App SDK namespaces). (Inherited from Layout)