Binding errors from under the hood

Trying to use grouping in DataGrid

and for no reason to get these binding errors (they don't belong in my code and I don't see a way to deal with them):

System.Windows.Data error: 4: Unable to find source for binding with reference 'RelativeSource FindAncestor, AncestorType =' System.Windows.Controls.DataGrid ', AncestorLevel =' 1 ''. BindingExpression: Path = AreRowDetailsFrozen; DataItem = NULL; the target is "DataGridDetailsPresenter" (Name = ''); target is "SelectiveScrollingOrientation" (type "SelectiveScrollingOrientation")

and

System.Windows.Data error: 4: Unable to find source to bind with reference 'RelativeSource FindAncestor, AncestorType =' System.Windows.Controls.DataGrid ', AncestorLevel =' 1 ''. BindingExpression: Path = HeadersVisibility; DataItem = NULL; target element - "DataGridRowHeader" (Name = ''); target is "Visibility" (type "Visibility")

They appear for every line in the DataGrid

. This worries me very much!

To reproduce the problem I made a small project

public class MyItem
{
    public string A { get; set; }
}

public class ViewModel
{
    public List<MyItem> List { get; set; }

    public ViewModel()
    {
        List = new List<MyItem>(new[] { new MyItem() });
    }
}

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
        DataContext = new ViewModel();
    }
}

      

        
        
        
      

    

XAML

<DataGrid ItemsSource="{Binding List}" AutoGenerateColumns="False">
    <DataGrid.Columns>
        <DataGridTextColumn Binding="{Binding A}" Header="A"/>
    </DataGrid.Columns>
    <DataGrid.GroupStyle>
        <GroupStyle>
            <GroupStyle.ContainerStyle>
                <Style TargetType="GroupItem">
                    <Setter Property="Template">
                        <Setter.Value>
                            <ControlTemplate TargetType="GroupItem">
                                <!-- anything or nothing here -->
                            </ControlTemplate>
                        </Setter.Value>
                    </Setter>
                </Style>
            </GroupStyle.ContainerStyle>
        </GroupStyle>
    </DataGrid.GroupStyle>
</DataGrid>

      

        
        
        
      

    

Some observations:

• no DataGrid.GroupStyle
  
  mistakes;
• with AutoGenerateColumns = true
  
  no errors;
• no linking (installing DataGrid.ItemsSource
  
  directly) no errors.

Only the combination opposite to these 3 conditions will trigger the mailing list Output

with the above messages.

What should I do? I cannot ignore the errors and I see no way to fix them.

Enabling googling was not really helpful, for example this case was called a bug, I tried to apply its workarounds, but none works for me.

PS: finding such errors on the first try is DataGrid

very demotivating.

Trying to deal with the second error.

<DataGrid.RowHeaderStyle>
    <Style TargetType="DataGridRowHeader">
        <Setter Property="Visibility" Value="Collapsed"/>
        <Setter Property="Template" Value="{x:Null}"/>
    </Style>
</DataGrid.RowHeaderStyle>

      

        
        
        
      

    

But the error is still

System.Windows.Data error: 4: Unable to find source to bind with reference 'RelativeSource FindAncestor, AncestorType =' System.Windows.Controls.DataGrid ', AncestorLevel =' 1 ''. BindingExpression: Path = HeadersVisibility; DataItem = NULL; target element - "DataGridRowHeader" (Name = ''); target is "Visibility" (type "Visibility")