Question

I want to add a new row in my Silverlight DataGrid, when user try to go from LastRow to NextRow by Tab/Enter (as it last row, DataGrid loses focus). I can not use RowEditEnded event as it will fire even if i move to a PreviousRow from LastRow.

Can anyone help me achieve this?

Answer 1

If you look at DataGrid source code you can see that it traps key down event (f.i. to realize functionality like go to next row on enter pressed). As solution I propose to implement own grid inherited from DataGrid and add event which raised when user presses enter(or other) button. Own control:

 public class MyDataGrid : DataGrid
 {
        public event EventHandler OnLastRowEnterPressed;

        protected override void OnKeyDown(KeyEventArgs e)
        {
            base.OnKeyDown(e);
                if (ItemsSource != null 
&& ItemsSource.Cast<object>().Count() - 1 == SelectedIndex 
&& e.Key == Key.Enter)
            {
                RaiseLastRowEnterPressed();
            }
        }

        private void RaiseLastRowEnterPressed()
        {
            if (OnLastRowEnterPressed != null)
                OnLastRowEnterPressed(this, EventArgs.Empty);
        }
 }

Using:

ObservableCollection<Foo> source = new ObservableCollection<Foo>()
                                  {
                                      new Foo(), new Foo(), new Foo(),
                                  };
myDataGrid.OnLastRowEnterPressed += (s, e) => source.Add(new Foo());
myDataGrid.ItemsSource = source;