AdvancedCollectionView ArgumentOutOfRangeException when remove the last element

[Dimigergo]

Describe the bug

When I use an AdvancedCollectionView and remove the last element from the bound collection the following exception thrown: 'System.ArgumentOutOfRangeException' in System.Private.CoreLib.dll Index was out of range. Must be non - negative and less than the size of the collection.

• Is this bug a regression in the toolkit?

Steps to Reproduce

• Can this be reproduced in the Sample App?

Steps to reproduce the behavior:

1. AdvancedCollectionView.zip
2. Start application
3. Click on 'Delete last'
4. See error in message box.

Expected behavior

The last element should be deleted without error.

Environment

NuGet Package(s):
Package Version(s):

    <PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform">
      <Version>6.2.12</Version>
    </PackageReference>
    <PackageReference Include="Microsoft.Toolkit.Uwp">
      <Version>7.1.0-rc2</Version>
    </PackageReference>
    <PackageReference Include="Microsoft.Toolkit.Uwp.UI">
      <Version>7.1.0-rc2</Version>
    </PackageReference>
    <PackageReference Include="Microsoft.Toolkit.Uwp.UI.Controls">
      <Version>7.1.0-rc2</Version>
    </PackageReference>

Windows 10 Build Number:

• Fall Creators Update (16299)
• April 2018 Update (17134)
• October 2018 Update (17763)
• May 2019 Update (18362)
• May 2020 Update (19041)
• Insider Build ({build_number})

App min and target version:

• Fall Creators Update (16299)
• April 2018 Update (17134)
• October 2018 Update (17763)
• May 2019 Update (18362)
• May 2020 Update (19041)
• Insider Build ({build_number})

Device form factor:

• Desktop
• Xbox
• Surface Hub
• IoT

Visual Studio version:

• 2017 (15.{minor_version})
• 2019 (16.11.3)
• 2022 (17.{minor_version})

[ghost]

Hello Dimigergo, thank you for opening an issue with us!

I have automatically added a "needs triage" label to help get things started. Our team will analyze and investigate the issue, and escalate it to the relevant team if possible. Other community members may also look into the issue and provide feedback 🙌

[michael-hawker]

Think this is a duplicate of #2913, thanks for providing a minimal repro project @Dimigergo.

Stack:

System.Private.CoreLib.dll!System.ThrowHelper.ThrowArgumentOutOfRange_IndexException()	Unknown
Microsoft.Toolkit.Uwp.UI.dll!Microsoft.Toolkit.Uwp.UI.AdvancedCollectionView.this[int].get(int index) Line 214	C#
Microsoft.Toolkit.Uwp.UI.Controls.DataGrid.dll!Microsoft.Toolkit.Uwp.UI.Controls.DataGridInternals.DataGridDataConnection.NotifyingDataSource_VectorChanged(Windows.Foundation.Collections.IObservableVector<object> sender, Windows.Foundation.Collections.IVectorChangedEventArgs e) Line 957	C#
Microsoft.Toolkit.Uwp.UI.dll!Microsoft.Toolkit.Uwp.UI.AdvancedCollectionView.OnVectorChanged(Windows.Foundation.Collections.IVectorChangedEventArgs e) Line 65	C#
Microsoft.Toolkit.Uwp.UI.dll!Microsoft.Toolkit.Uwp.UI.AdvancedCollectionView.SourceNcc_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e) Line 629	C#
System.ObjectModel.dll!System.Collections.ObjectModel.ObservableCollection<AdvancedCollectionView.MainPage.CValami>.OnCollectionChanged(System.Collections.Specialized.NotifyCollectionChangedEventArgs e)	Unknown
AdvancedCollectionView.exe!AdvancedCollectionView.MainPage.ButtonClick(object sender, Windows.UI.Xaml.RoutedEventArgs e) Line 91	C#

get:

WindowsCommunityToolkit/Microsoft.Toolkit.Uwp.UI/AdvancedCollectionView/AdvancedCollectionView.cs

Lines 212 to 216 in 760ab9f

	public object this[int index]
	{
	get { return _view[index]; }
	set { _view[index] = value; }
	}

removeAt:

WindowsCommunityToolkit/Microsoft.Toolkit.Uwp.UI.Controls.DataGrid/DataGrid/DataGridDataConnection.cs

Lines 952 to 958 in 760ab9f

	case CollectionChange.ItemRemoved:
	if (!this.IsGrouping)
	{
	// If we're grouping then we handle this through the CollectionViewGroup notifications.
	// Remove is a single item operation.
	_owner.RemoveRowAt(index, sender[index]);
	}

OnVectorChanged:

WindowsCommunityToolkit/Microsoft.Toolkit.Uwp.UI/AdvancedCollectionView/AdvancedCollectionView.Events.cs

Lines 55 to 66 in 760ab9f

	private void OnVectorChanged(IVectorChangedEventArgs e)
	{
	if (_deferCounter > 0)
	{
	return;
	}
	VectorChanged?.Invoke(this, e);
	// ReSharper disable once ExplicitCallerInfoArgument
	OnPropertyChanged(nameof(Count));
	}

WindowsCommunityToolkit/Microsoft.Toolkit.Uwp.UI/AdvancedCollectionView/AdvancedCollectionView.cs

Lines 627 to 639 in 760ab9f

	case NotifyCollectionChangedAction.Remove:
	DetachPropertyChangedHandler(e.OldItems);
	if (_deferCounter <= 0)
	{
	if (e.OldItems?.Count == 1)
	{
	HandleItemRemoved(e.OldStartingIndex, e.OldItems[0]);
	}
	else
	{
	HandleSourceChanged();
	}
	}

WindowsCommunityToolkit/Microsoft.Toolkit.Uwp.UI/AdvancedCollectionView/AdvancedCollectionView.cs

Lines 741 to 751 in 760ab9f

	private void RemoveFromView(int itemIndex, object item)
	{
	_view.RemoveAt(itemIndex);
	if (itemIndex <= CurrentPosition)
	{
	CurrentPosition--;
	}
	var e = new VectorChangedEventArgs(CollectionChange.ItemRemoved, itemIndex, item);
	OnVectorChanged(e);
	}

So, I think the issue here is DataGrid is trying to retrieve the item to know which one is removed, but it's already been removed from the collection when the event is called. Normally with an INotifyCollectionChanged event the item is provided in the event args, but that doesn't seem to be the case with the IVectorChangedEventArgs

If we swap the DataGrid for a ListView, things work fine. This seems to work fine in Wpf as they use the collectionchangedevent compared to an observablevector. FYI @RBrid.

[Mirofire]

Is this issue still open? I getting the same issue with Nuget package CommunityToolkit.WinUI.UI.Controls Version: 7.1.2