ContextMenu Command Binding to parent and to self - wpf

Question

I am trying to create a ContextMenu on a DataGrid with multiple Command Bindings. Some have to be bound to the local ViewModel (i.e. the ViewModel of the Row) and some to the parents ViewModel.
I had no luck so far following other solutions. I only get the SubCommand to execute.
MainViewModel
public class MainViewModel : ViewModelBase
{
public ObservableCollection<SubViewModel> Items { get; private set; }
public MainViewModel()
{
Items = new ObservableCollection<SubViewModel>();
Items.Add(new SubViewModel());
Items.Add(new SubViewModel());
}
private RelayCommand _mainCommand;
public ICommand MainCommand
{
get
{
if (_mainCommand == null)
{
_mainCommand = new RelayCommand(
() =>
{
Debug.WriteLine("MAINCOMMAND EXECUTED");
}
);
}
return _mainCommand;
}
}
}
SubViewModel
public class SubViewModel : ViewModelBase
{
private RelayCommand _subCommand;
public ICommand SubCommand
{
get
{
if (_subCommand == null)
{
_subCommand = new RelayCommand(
() =>
{
Debug.WriteLine("SUBCOMMAND EXECTUED");
}
);
}
return _subCommand;
}
}
}
MainWindow
<Window x:Class="WpfApplication4.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow"
Width="525"
Height="350"
DataContext="{Binding Source={StaticResource Locator},
Path=Main}">
<Grid>
<DataGrid ItemsSource="{Binding Items}">
<DataGrid.RowStyle>
<Style TargetType="{x:Type DataGridRow}">
<Setter Property="ContextMenu">
<Setter.Value>
<ContextMenu DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}">
<MenuItem Command="{Binding DataContext.MainCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type ContextMenu}}}" Header="Main" />
<MenuItem Command="{Binding SubCommand}" Header="Sub" />
</ContextMenu>
</Setter.Value>
</Setter>
</Style>
</DataGrid.RowStyle>
</DataGrid>
</Grid>
</Window>

Answer 1

I have found a way, but I don't think it is too elegant, maybe there is a better way, but this will work:
<Window x:Class="WpfApplication4.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow"
Width="525"
Height="350"
DataContext="{Binding Source={StaticResource Locator},
Path=Main}">
<Grid x:Name="Grid">
<DataGrid x:Name="DataGrid" ItemsSource="{Binding Items}">
<DataGrid.RowStyle>
<Style TargetType="{x:Type DataGridRow}">
<Setter Property="ContextMenu">
<Setter.Value>
<ContextMenu>
<MenuItem Command="{Binding Path=PlacementTarget.Tag.MainCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type ContextMenu}}}" Header="Main" />
<MenuItem Command="{Binding SubCommand}" Header="Sub" />
</ContextMenu>
</Setter.Value>
</Setter>
<Setter Property="Tag" Value="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type DataGrid}}, Path=DataContext}" />
</Style>
</DataGrid.RowStyle>
</DataGrid>
</Grid>
</Window>