when you click close, an error is reported.

Operation is not valid while ItemsSource is in use. Access and modify elements with LayoutGroup.ItemsSource instead.

xaml Code

<dxdo:DocumentGroup x:Name="UIDocmentGroup" DataContext="{Binding DocumentGroupVM}" ItemsSource="{Binding TabDatas}">
                                <dxdo:DocumentGroup.ItemCaptionTemplate>
                                    <DataTemplate>
                                        <TextBlock Text="{Binding Name}"></TextBlock>
                                    </DataTemplate>
                                </dxdo:DocumentGroup.ItemCaptionTemplate>
                                <dxdo:DocumentGroup.ItemContentTemplate>
                                    <DataTemplate>
                                        <my:CustomDocumentGroupItem ItemSource="{Binding}"></my:CustomDocumentGroupItem>
                                    </DataTemplate>
                                </dxdo:DocumentGroup.ItemContentTemplate>
                            </dxdo:DocumentGroup>

where the ItemsSource of DocumentGroup is bound to the object.

it is estimated that when the point is closed, the ui is deleted, but the bound collection is not deleted.

how to deal with this?