WPF datagrid 'newitemplaceholderposition' is not allowed during a transaction begun by 'addnew'

Question

I have a tabControl on a WPF form.

In one of the Tab Items I have a User Control that contains a DataGrid which has CanUserAddRows="True". The

Answer 1

I just ran into the same problem. Found two possible workarounds:

1/ Trigger the CommitEdit event of the DataGrid, then call CommitEdit. I'm not sure why this last step is needed, you may not have to call CommitEdit in your case.

        DataGrid.CommitEditCommand.Execute(this.DataGridWorkItems, this.DataGridWorkItems);

        yourDataGrid.CommitEdit(DataGridEditingUnit.Row, false);

2/ Simulate a stroke on the 'Return' key of the keyboard:

        var keyEventArgs = new KeyEventArgs(InputManager.Current.PrimaryKeyboardDevice,PresentationSource.FromDependencyObject(yourDataGrid), System.Environment.ProcessorCount, Key.Return);
        keyEventArgs.RoutedEvent = UIElement.KeyDownEvent;
        yourDataGrid.RaiseEvent(keyEventArgs);

I settled for the last solution, since I had a few fishy side effects with the first one.