Can you filter an ICollectionView in an UWP app?-CodePudding

I'm still learning C# by developing a small UWP app. Basically my app fetches my owned Steam games and adds them asynchronously to an ObservableCollection. Which adds the games to the Gridview.

XAML:

<GridView
    x:Name="BasicGridView"
    ItemsSource="{Binding}"
    ItemTemplate="{StaticResource ImageTemplate}"
    IsItemClickEnabled="True"
    ItemClick="BasicGridView_ItemClick"
    SelectionMode="Single"
    Margin="15, 0, 0, 0"
>
    <GridView.ItemContainerStyle>
        <Style TargetType="GridViewItem">
            <Setter Property="Margin" Value="0, 15, 15, 0"/>
        </Style>
    </GridView.ItemContainerStyle>
</GridView>

C# code:

// My games list
public ObservableCollection<Game> OwnedGames { get; set; }

// Binding my games list to the GridView
BasicGridView.DataContext = OwnedGames;

Now my next step is to add filtering. After some search, it seems a solution is to use a CollectionViewSource.

This is what I ended up with:

public ICollectionView OwnedGamesView { get; set; }

CollectionViewSource OwnedGamesViewSource = new CollectionViewSource();
OwnedGamesViewSource.Source = OwnedGames;
OwnedGamesView = OwnedGamesViewSource.View;

Since I would use a CollectionView now, I changed the Datacontext of the GridView like this:

BasicGridView.DataContext = OwnedGamesView;

When running the app, everything still works like this, so the last step would have been to perform the filtering itself:

OwnedGamesView.Filter(...);

However this method doesn't exist in my case. It isn't listed on the ICollectionView API reference for UWP: https://docs.microsoft.com/en-us/uwp/api/windows.ui.xaml.data.icollectionview?view=winrt-20348

So I am wondering how I can still make this work within an UWP app? Or what a possible alternative is?

I hope my question is clear? Thanks in advance! :)

CodePudding user response：

Filtering using a CollectionViewSource is not done on the resulting View collection, but the CollectionViewSource instance itself. Add an event listener to the CollectionViewSource.Filter event. See an example here.

CodePudding user response：

However this method doesn't exist in my case. It isn't listed on the ICollectionView API reference for UWP

ICollectionView does not contain Filter, for your requirement, you could use Microsoft.Toolkit AdvancedCollectionView class to approach. It contains Filter property, you could use it to filter the collection and set SortDescriptions.

var acv = new AdvancedCollectionView(oc);

// Let's filter out the integers
int nul;
acv.Filter = x => !int.TryParse(((Person)x).Name, out nul);

// And sort ascending by the property "Name"
acv.SortDescriptions.Add(new SortDescription("Name", SortDirection.Ascending));

// AdvancedCollectionView can be bound to anything that uses collections. In this case there are two ListViews, one for the original and one for the filtered-sorted list.
RightList.ItemsSource = acv;