attached DependencyProperty not found when declared in classlib

[Al-Caron]

Describe the bug

I wrote a simple attached property "AutoScrollOnSelect" in my "control classlib". The main application (WinUI 3 unpackaged app )that wants to use it can't find it :

2>D:\sources\ced\ev2557\cln\dotnet\DashCed\Pages\PagePannes.xaml(149,22): XamlCompiler error WMC0010: Unknown attachable member 'DataGridExtension.AutoScrollOnSelect' on element 'DataGrid'

Steps to reproduce the bug

1. Create a WinUI3 Classlib that can contains UI classes.
2. Create the attachedProperty
   `using CommunityToolkit.WinUI.UI.Controls;
   using Microsoft.UI.Xaml;
   using System.Linq;

namespace CGI.Ced.WinUI.Controls.Extensions;

public class DataGridExtension
{

public static readonly DependencyProperty AutoScrollOnSelectProperty = DependencyProperty.RegisterAttached("AutoScrollOnSelect", typeof(bool), typeof(DataGridExtension), new PropertyMetadata(false, OnAutoScrollOnSelectChanged));


private static void OnAutoScrollOnSelectChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
    if (d is DataGrid dataGrid)
    {
        dataGrid.SelectionChanged += DataGrid_SelectionChanged;
        dataGrid.Loaded += DataGrid_Loaded;
        dataGrid.Unloaded += DataGrid_Unloaded;
    }
}

private static void DataGrid_Unloaded(object sender, RoutedEventArgs e)
{
    DataGrid dataGrid = sender as DataGrid;
    if (dataGrid != null)
    {
        dataGrid.SelectionChanged -= DataGrid_SelectionChanged;
        dataGrid.Loaded -= DataGrid_Loaded;
    }
}

private static void DataGrid_Loaded(object sender, RoutedEventArgs e)
{
    DataGrid grid = sender as DataGrid;
    if (grid != null && grid.SelectedItem != null)
    {
        if (grid.SelectedItem != null)
        {
            grid.UpdateLayout();
            grid.ScrollIntoView(grid.SelectedItem, null);
        }
    }
}

private static void DataGrid_SelectionChanged(object sender, Microsoft.UI.Xaml.Controls.SelectionChangedEventArgs e)
{
    DataGrid grid = sender as DataGrid;
    if (grid != null && grid.IsLoaded)
    {
        var item = e.AddedItems.LastOrDefault();
        if (item != null)
        {
            grid.UpdateLayout();
            grid.ScrollIntoView(item, null);
        }
    }
}

public static void SetAutoScrollOnSelect(UIElement d, bool value)
{
    d.SetValue(AutoScrollOnSelectProperty, value);
}

public static bool GetAutoScrollOnSelect(UIElement obj)
{
    return (bool)obj.GetValue(AutoScrollOnSelectProperty);
}

}
3. In WinUI3 app, inside a page, use the property: xmlns:dgext="using:CGI.WinUI.Controls.Extensions" <dg:DataGrid ItemsSource="{Binding Path=Interruptions}"
AutoGenerateColumns="False"
Grid.Row="1" IsReadOnly="True"
SelectionMode="Single"
RowDetailsVisibilityMode="VisibleWhenSelected"
RowDetailsTemplate="{StaticResource PanneDataTemplate}"
dgext:DataGridExtension.AutoScrollOnSelect="True" <!- HERE!!!!!!!!!!!! -->
SelectedItem="{Binding Path=SelectedItem, Mode=TwoWay}">`

Expected behavior

Attached property to be found, and program to compile.

Screenshots

NuGet package version

WinUI 3 - Windows App SDK 1.4.3: 1.4.231115000

Windows version

Windows 10 (1809): Build 17763

Additional context

Interesting, the same attached property when moved into the main Application assembly works perfectly. It is really the fact that it's located inside another assembly that seems to be the problem.

No response

[Al-Caron]

Sorry, Closing... I found my problem!!!!!!

I'm terribly sorry. Error in character casing in the namespace. Don't know why it didn't show up. Working fine!