`hc:ListBoxAttach.SelectedItems` binding got `null`

[GF-Huang]

Describe the bug

https://github.com/HandyOrg/HandyControl/assets/4510984/a7ecdee8-7ce4-42f8-86dd-7c45959c71a3

Steps to reproduce the bug

Codes to reproduce

<hc:Window ...>
  <hc:CheckComboBox VerticalAlignment="Center" HorizontalAlignment="Center" Width="300"
                    ItemsSource="{Binding DataList}" hc:ListBoxAttach.SelectedItems="{Binding SelectedDataItems}" />
</hc:Window>

public class RootViewModel : PropertyChangedBase {
    public IReadOnlyList<string> DataList { get; } = ["1", "2", "3"];

    public List<string> SelectedDataItems { get; set; } = [];
}

CheckComboBoxDemo.zip

Expected behavior

No response

Screenshots

No response

NuGet package version

HandyControl 3.5.1

IDE

Visual Studio 2022

Framework type

.Net 8.0

Windows version

Windows 11 23H2

Additional context

No response

[GF-Huang]

Solved by change List<string> SelectedDataItems to IList SelectedDataItems.

[blackvon-sudo]

Solved by change List<string> SelectedDataItems to IList SelectedDataItems.

It's not worked

[GF-Huang]

Solved by change List<string> SelectedDataItems to IList SelectedDataItems.

It's not worked

Make sure it is IList not IList<T>.