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CollectionViewSource Class

Definition

Provides a data source that adds grouping and current-item support to collection classes.

public ref class CollectionViewSource sealed : DependencyObject
/// [Windows.Foundation.Metadata.Activatable(65536, "Microsoft.UI.Xaml.WinUIContract")]
/// [Windows.Foundation.Metadata.ContractVersion(Microsoft.UI.Xaml.WinUIContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
class CollectionViewSource final : DependencyObject
[Windows.Foundation.Metadata.Activatable(65536, "Microsoft.UI.Xaml.WinUIContract")]
[Windows.Foundation.Metadata.ContractVersion(typeof(Microsoft.UI.Xaml.WinUIContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
public sealed class CollectionViewSource : DependencyObject
Public NotInheritable Class CollectionViewSource
Inherits DependencyObject
<CollectionViewSource .../>
Inheritance
Object Platform::Object IInspectable DependencyObject CollectionViewSource
Attributes

Examples

Tip

For more info, design guidance, and code examples, see Semantic zoom.

The WinUI 3 Gallery app includes interactive examples of most WinUI 3 controls, features, and functionality. Get the app from the Microsoft Store or get the source code on GitHub.

The following code example demonstrates how to bind a ListBox control to the results of a grouping LINQ query. In this example, a collection of teams is grouped by city and displayed with the city name as the group headers. For the complete code listing, see the XAML data binding sample.

<Grid>

  <Grid.Resources>
    <CollectionViewSource x:Name="groupInfoCVS" IsSourceGrouped="true"/>
  </Grid.Resources>

  <ListBox x:Name="lbGroupInfoCVS" 
    ItemsSource="{Binding Source={StaticResource groupInfoCVS}}">

    <ListBox.GroupStyle>
      <GroupStyle>
        <GroupStyle.HeaderTemplate>
          <DataTemplate>

            <TextBlock Text="{Binding Key}"/>

          </DataTemplate>
        </GroupStyle.HeaderTemplate>
      </GroupStyle>
    </ListBox.GroupStyle>

    <ListBox.ItemTemplate>
      <DataTemplate>

        <Border Background="{Binding Color}" 
          Width="200" CornerRadius="10" HorizontalAlignment="Left">

          <TextBlock Text="{Binding Name}" 
            Style="{StaticResource DescriptionTextStyle}" 
            HorizontalAlignment="Center" FontWeight="Bold"/>

        </Border>
      </DataTemplate>
    </ListBox.ItemTemplate>

  </ListBox>

</Grid>
Teams teams = new Teams();
var result = 
    from t in teams 
    group t by t.City into g 
    orderby g.Key 
    select g;
groupInfoCVS.Source = result;

Remarks

Use CollectionViewSource when you want to bind list controls to collections, but you want to display those collections in groups and maintain a current item independent from the list control. This is particularly useful when you want to bind multiple controls to the same collection and you want the current item in one control to change the current item in the other bound controls. You typically define a CollectionViewSource as a XAML resource and bind to it using the {StaticResource} markup extension. You can then set its Source property in code-behind to a supported collection type.

Any controls that you bind to the same CollectionViewSource will always have the same current item. You can access the current item programmatically through the ICollectionView.CurrentItem property of the CollectionViewSource.View property value.

If the items in the collection are collections themselves, or are objects that contain collections, you can display the collections as groups within the larger collection. To do this, set the IsSourceGrouped property to true. If the items contain collections but are not collections themselves, you must also set the ItemsPath property to the name of the collection property.

Note

Setting the Source property to another CollectionViewSource instance is not supported.

Constructors

CollectionViewSource()

Initializes a new instance of the CollectionViewSource class.

Properties

Dispatcher

Always returns null in a Windows App SDK app. Use DispatcherQueue instead.

(Inherited from DependencyObject)
DispatcherQueue

Gets the DispatcherQueue that this object is associated with. The DispatcherQueue represents a facility that can access the DependencyObject on the UI thread even if the code is initiated by a non-UI thread.

(Inherited from DependencyObject)
IsSourceGrouped

Gets or sets a value that indicates whether source data is grouped.

IsSourceGroupedProperty

Identifies the IsSourceGrouped dependency property.

ItemsPath

Gets or sets the property path to follow from the top level item to find groups within the CollectionViewSource.

ItemsPathProperty

Identifies the ItemsPath dependency property.

Source

Gets or sets the collection object from which to create this view.

SourceProperty

Identifies the Source dependency property.

View

Gets the view object that is currently associated with this instance of CollectionViewSource.

ViewProperty

Identifies the View dependency property.

Methods

ClearValue(DependencyProperty)

Clears the local value of a dependency property.

(Inherited from DependencyObject)
GetAnimationBaseValue(DependencyProperty)

Returns any base value established for a dependency property, which would apply in cases where an animation is not active.

(Inherited from DependencyObject)
GetValue(DependencyProperty)

Returns the current effective value of a dependency property from a DependencyObject.

(Inherited from DependencyObject)
ReadLocalValue(DependencyProperty)

Returns the local value of a dependency property, if a local value is set.

(Inherited from DependencyObject)
RegisterPropertyChangedCallback(DependencyProperty, DependencyPropertyChangedCallback)

Registers a notification function for listening to changes to a specific DependencyProperty on this DependencyObject instance.

(Inherited from DependencyObject)
SetValue(DependencyProperty, Object)

Sets the local value of a dependency property on a DependencyObject.

(Inherited from DependencyObject)
UnregisterPropertyChangedCallback(DependencyProperty, Int64)

Cancels a change notification that was previously registered by calling RegisterPropertyChangedCallback.

(Inherited from DependencyObject)

Applies to

See also