WPF DataGrid not exiting edit mode

Question

I have a DataGrid displaying several rows and columns of data, each is bound to its own Property. The DataGrid is NOT on a TabControl but whenever the window that it lives on is closed and reopened I get the error message: 'DeferRefresh' is not allowed during an AddNew or EditItem transaction. ONLY IF there were validations issues with one or more of the DataGrid's cells.

For example: The property bound to the DataGrid's cell is a double and the user enters "hello", of course then WPF's automatic red border is displayed around the cell. Now, if the user were to close the window, and reopen it the error would occur.

I know why the error is being thrown, because the cell is not leaving "edit mode".

How can I resolve this error?

Other Notes:

• I have looked at this question but that is pertaining to a DataGrid on a TabControl (which mine is not).
• I have attempted to limit the user's input so that if the Cell requires a double or then only accept a double, but the problem is there are no good ways to limit the number of decimal points (".") that the user can insert. I am controlling user input through PreviewTextInput and only allowing 0-9 and ".".

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Exception Detail (if this helps)

System.InvalidOperationException was unhandled
  Message='DeferRefresh' is not allowed during an AddNew or EditItem transaction.
  Source=PresentationFramework
  StackTrace:
       at System.Windows.Data.CollectionView.DeferRefresh()
       at System.Windows.Controls.ItemCollection.SetCollectionView(CollectionView view)
       at System.Windows.Controls.ItemsControl.OnItemsSourceChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
       at System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
       at System.Windows.FrameworkElement.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
       at System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args)
       at System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
       at System.Windows.Data.BindingExpressionBase.Invalidate(Boolean isASubPropertyChange)
       at System.Windows.Data.BindingExpression.TransferValue(Object newValue, Boolean isASubPropertyChange)
       at System.Windows.Data.BindingExpression.Activate(Object item)
       at System.Windows.Data.BindingExpression.AttachToContext(AttachAttempt attempt)
       at System.Windows.Data.BindingExpression.MS.Internal.Data.IDataBindEngineClient.AttachToContext(Boolean lastChance)
       at MS.Internal.Data.DataBindEngine.Task.Run(Boolean lastChance)
       at MS.Internal.Data.DataBindEngine.Run(Object arg)
       at MS.Internal.Data.DataBindEngine.OnLayoutUpdated(Object sender, EventArgs e)
       at System.Windows.ContextLayoutManager.fireLayoutUpdateEvent()
       at System.Windows.ContextLayoutManager.UpdateLayout()
       at System.Windows.Interop.HwndSource.SetLayoutSize()
       at System.Windows.Interop.HwndSource.set_RootVisualInternal(Visual value)
       at System.Windows.Window.SetRootVisualAndUpdateSTC()
       at System.Windows.Window.SetupInitialState(Double requestedTop, Double requestedLeft, Double requestedWidth, Double requestedHeight)
       at System.Windows.Window.CreateSourceWindow(Boolean duringShow)
       at System.Windows.Window.ShowHelper(Object booleanBox)
       at REACT.ViewModel.ReceiverListViewModel.ShowWindow(String name) in C:\Users\jcarroll42\Documents\Sandbox\REACT\SW\Source\ViewModel\ReceiverListViewModel.cs:line 238
       at REACT.Commands.ShowWindowCommand.Execute(Object parameter) in C:\Users\jcarroll42\Documents\Sandbox\REACT\SW\Source\Commands.cs:line 137
       at MS.Internal.Commands.CommandHelpers.CriticalExecuteCommandSource(ICommandSource commandSource, Boolean userInitiated)
       at System.Windows.Controls.Button.OnClick()
       at System.Windows.Controls.Primitives.ButtonBase.OnMouseLeftButtonUp(MouseButtonEventArgs e)
       at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
       at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
       at System.Windows.UIElement.ReRaiseEventAs(DependencyObject sender, RoutedEventArgs args, RoutedEvent newEvent)
       at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
       at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
       at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
       at System.Windows.UIElement.RaiseTrustedEvent(RoutedEventArgs args)
       at System.Windows.Input.InputManager.ProcessStagingArea()
       at System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport)
       at System.Windows.Interop.HwndMouseInputProvider.ReportInput(IntPtr hwnd, InputMode mode, Int32 timestamp, RawMouseActions actions, Int32 x, Int32 y, Int32 wheel)
       at System.Windows.Interop.HwndMouseInputProvider.FilterMessage(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
       at System.Windows.Interop.HwndSource.InputFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
       at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
       at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
       at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
       at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
       at System.Windows.Threading.Dispatcher.WrappedInvoke(Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
       at System.Windows.Threading.Dispatcher.InvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
       at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
       at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
       at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
       at System.Windows.Application.RunInternal(Window window)
       at System.Windows.Application.Run()
       at REACT.App.Main() in C:\Users\jcarroll42\Documents\Sandbox\REACT\SW\Source\obj\x86\Debug\App.g.cs:line 0
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: 

I'll be happy to provide anymore information if needed.

Answer 1

You can try to force datagrid into cancelling edition when you need it:

myDatagrid.CommitEdit(); 
myDatagrid.CancelEdit();

This worked for me, i had a similar issue when reordering rows.

Answer 2

This is a bug that was fixed with .NET Framework 4.5+. Unfortunately, for those of us stuck with previous versions the error is still a problem. The best solution I have found is to simply bind the DataGrid to properties with type string. That way, full control over user input is available. With full control, the user should not be able to trigger any errors, and theDataGrid will not crash the program.