WPF › Virtualizing Collection View › VirtualizingCollectionView

VirtualizingCollectionView

class.NET 6 / 8 / 10.NET Framework 4.8Binarymission.WPF.Data.DataExtensions

A custom class that supports rendering group headers for Binarymission VirtualizingWrappanel control.

public sealed class VirtualizingCollectionView : ListCollectionView

Inherits from / implements: ListCollectionView

Members at a glance

`VirtualizingCollectionView`	Initializes a new instance of the `VirtualizingCollectionView` class.
`Count`	Gets the estimated number of records.
`Groups`	Gets the top-level groups.
`GroupsCount`	Gets the groups count.
`GetCheckForVirtualizedGroupHeaders`	Gets whether to check for virtualized group headers.
`GetIsCurrentItemAVirtualizedGroupHeader`	Gets whether the current item is a virtualized group header.
`GetItemAt`	Retrieves the item at the specified position in the view.
`OnCollectionChanged`	Raises the CollectionChanged event. VirtualizingCollectionView overrides it so the control's own handling runs alongside the base behavior.
`SetCheckForVirtualizedGroupHeaders`	Sets whether to check for virtualized group headers.
`SetIsCurrentItemAVirtualizedGroupHeaderProperty`	Sets whether the current item is a virtualized group header.
`CheckForVirtualizedGroupHeadersProperty`	Gets or sets as to whether to check for virtualized group headers.
`IsCurrentItemAVirtualizedGroupHeaderProperty`	Gets or sets as to whether the current item is a virtualized group header.

Constructors

VirtualizingCollectionView

public VirtualizingCollectionView(IList list) : base(list)

Initializes a new instance of the VirtualizingCollectionView class.

list: The underlying collection, which must implement IList.

Properties

Count

public override int Count

Gets the estimated number of records.

Returns. One of the following: Value Meaning -1 Could not determine the count of the collection. This might be returned by a "virtualizing" view, where the view deliberately does not account for all items in the underlying collection because the view is attempting to increase efficiency and minimize dependence on always having the entire collection available. any other integer The count of the collection.

Groups

public override ReadOnlyObservableCollection<object> Groups

Gets the top-level groups.

Returns. A read-only collection of the top-level groups, or null if there are no groups.

GroupsCount

public int GroupsCount

Gets the groups count.

Value. The groups count.

Methods

GetCheckForVirtualizedGroupHeaders

public static bool GetCheckForVirtualizedGroupHeaders(DependencyObject obj)

Gets whether to check for virtualized group headers.

GetIsCurrentItemAVirtualizedGroupHeader

public static bool GetIsCurrentItemAVirtualizedGroupHeader(DependencyObject obj)

Gets whether the current item is a virtualized group header.

GetItemAt

public override object GetItemAt(int index)

Retrieves the item at the specified position in the view.

index: The zero-based index at which the item is located.

Returns. The item at the specified position in the view.

ArgumentOutOfRangeException: If index is out of range.

OnCollectionChanged

protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs args)

Raises the CollectionChanged event. VirtualizingCollectionView overrides it so the control's own handling runs alongside the base behavior.

args: The data for the event.

SetCheckForVirtualizedGroupHeaders

public static void SetCheckForVirtualizedGroupHeaders(DependencyObject obj, bool value)

Sets whether to check for virtualized group headers.

SetIsCurrentItemAVirtualizedGroupHeaderProperty

public static void SetIsCurrentItemAVirtualizedGroupHeaderProperty(DependencyObject obj, bool value)

Sets whether the current item is a virtualized group header.

Fields

CheckForVirtualizedGroupHeadersProperty

public static readonly DependencyProperty CheckForVirtualizedGroupHeadersProperty

Gets or sets as to whether to check for virtualized group headers.

IsCurrentItemAVirtualizedGroupHeaderProperty

public static readonly DependencyProperty IsCurrentItemAVirtualizedGroupHeaderProperty

Gets or sets as to whether the current item is a virtualized group header.