隐藏窗口时出现InvalidOperationException

我'm writing a simple form on WPF, and it works fine. But now I should change target framework from 4 to 3.5. But when i' m运行3.5版本，它失败了除了 . 所以 OnLoaded 是这样的：

private void MainWindow_OnLoaded(object sender, RoutedEventArgs e)
    {
        _notificator = new Notificator(Directory.GetCurrentDirectory());
        _notificator.EventStarted += (o, ev) => Dispatcher.Invoke(new Action(() =>
                                                                        {
                                                                            new NotificationPage(ev).Show();
                                                                            _collection.Remove(ev);
                                                                        }));
        _notificator.EventRemoved += (o, ev) => _collection.Remove(ev);
        _notificator.EventAdded += (o, ev) => _collection.Insert(_notificator.Events.IndexOf(ev), ev);
        _collection = new ObservableCollection<MyEvent>(_notificator.Events);
        EventsGrid.DataContext = _collection;
        _notificator.Start();
        LostEventsGrid.DataContext = _notificator.LostEvents;
        Hide();
    }

我编写了整个方法，但它仅在使用 Two-way binding requires Path or XPath 的Hide方法时失败 . 堆栈跟踪：

вSystem.Windows.Data.BindingExpression.CreateBindingExpression（DependencyObject d，DependencyProperty dp，Binding binding，BindingExpressionBase parent） - System.Windows.Data.Binding.CreateBindingExpressionOverride（DependencyObject target，DependencyProperty dp，BindingExpressionBase owner） - System.Windows.Data .BindingOperations.SetBinding（DependencyObject目标，DependencyProperty dp，BindingBase绑定） - Microsoft.Windows.Controls.DataGridBoundColumn.ApplyBinding（DependencyObject目标，DependencyProperty属性） - Microsoft.Windows.Controls.DataGridTextColumn.GenerateElement（DataGridCell cell，Object dataItem）•Microsoft .Windows.Controls.DataGridColumn.BuildVisualTree（Boolean isEditing，Object dataItem，DataGridCell cell） - Microsoft.Windows.Controls.DataGridCell.BuildVisualTree（） - Microsoft.Windows.Controls.DataGridCell.PrepareCell（Object item，DataGridRow ownerRow，Int32 index） Microsoft.Windows.Controls.DataGridCell.PrepareCell（Object item，ItemsControl cel lsPresenter，DataGridRow ownerRow）Microsoft.Windows.Controls.Primitives.DataGridCellsPresenter.PrepareContainerForItemOverride（DependencyObject element，Object item）вSystem.Windows.Controls.ItemsControl.MS.Internal.Controls.IGeneratorHost.PrepareItemContainer（DependencyObject container，Object item） System.Windows.Controls.ItemContainerGenerator.System.Windows.Controls.Primitives.IItemContainerGenerator.PrepareItemContainer（DependencyObject容器） - Microsoft.Windows.Controls.DataGridCellsPanel.InsertContainer（Int32 childIndex，UIElement容器，Boolean isRecycled） - Microsoft.Windows.Controls . DataGridCellsPanel.InsertNewContainer（Int32 childIndex，UIElement容器） - Microsoft.Windows.Controls.DataGridCellsPanel.AddContainerFromGenerator（Int32 childIndex，UIElement child，BooleannewRealized） - Microsoft.Windows.Controls.DataGridCellsPanel.GenerateChild（IItemContainerGenerator generator，Size constraint，DataGridColumn column， Int32＆childIndex，Size＆childSi ze.Microsoft.Windows.Controls.DataGridCellsPanel.GenerateChildren（IItemContainerGenerator generator，Int32 startIndex，Int32 endIndex，Size constraint）вMicrosoft.Windows.Controls.DataGridCellsPanel.GenerateAndMeasureChildrenForRealizedColumns（Size constraint）вMicrosoft.Windows.Controls.DataGridCellsPanel.MeasureOverride（大小约束）вSystem.Windows.FrameworkElement.MeasureCore（Size availableSize）вSystem.Windows.UIElement.Measure（Size availableSize）вMS.Internal.Helper.MeasureElementWithSingleChild（UIElement element，Size constraint）вSystem.Windows.Controls.ItemsPresenter .MeasureOverride（大小约束）вSystem.Windows.FrameworkElement.MeasureCore（Size availableSize）вSystem.Windows.UIElement.Measure（Size availableSize）вSystem.Windows.Controls.Control.MeasureOverride（Size constraint）вMicrosoft.Windows.Controls .Primitives.DataGridCellsPresenter.MeasureOverride（Size availableSize）вSystem.Windows.FrameworkElement.MeasureCore（Size availableSize）вSyst em.Windows.UIElement.Measure（Size availableSize）вSystem.Windows.Controls.Grid.MeasureCell（Int32 cell，Boolean forceInfinityV）вSystem.Windows.Controls.Grid.MeasureCellsGroup（Int32 cellsHead，Size referenceSize，Boolean ignoreDesiredSizeU，Boolean forceInfinityV ）System.Windows.Controls.Grid.MeasureOverride（Size constraint）вSystem.Windows.FrameworkElement.MeasureCore（Size availableSize）вSystem.Windows.UIElement.Measure（Size availableSize）вSystem.Windows.Controls.Border.MeasureOverride（大小约束）вSystem.Windows.FrameworkElement.MeasureCore（Size availableSize）вSystem.Windows.UIElement.Measure（Size availableSize）вSystem.Windows.Controls.Control.MeasureOverride（Size constraint）вSystem.Windows.FrameworkElement.MeasureCore（ Size availableSize）вSystem.Windows.UIElement.Measure（Size availableSize）вSystem.Windows.Controls.VirtualizingStackPanel.MeasureOverride（Size constraint）вMicrosoft.Windows.Controls.Primitives.DataGridRowsPresenter.MeasureOverride（S ize约束）вSystem.Windows.FrameworkElement.MeasureCore（Size availableSize）вSystem.Windows.UIElement.Measure（Size availableSize）вSystem.Windows.ContextLayoutManager.UpdateLayout（）вSystem.Windows.Interop.HwndSource.Process_WM_SIZE（UIElement rootUIElement ，IntPtr hwnd，Int32 msg，IntPtrwParam，IntPtr lParam）вSystem.Windows.Interop.HwndSource.LayoutFilterMessage（IntPtr hwnd，Int32 msg，IntPtr wParam，IntPtr lParam，Boolean＆handling）вMS.Win32.HwndWrapper.WndProc（IntPtr hwnd，Int32 msg，IntPtr wParam，IntPtr lParam，Boolean＆handling）вMS.Win32.HwndSubclass.DispatcherCallbackOperation（Object o）вSystem.Windows.Threading.ExceptionWrapper.InternalRealCall（Delegate callback，Object args，Boolean isSingleParameter）вSystem.Windows.Threading.ExceptionWrapper.TryCatchWhen（Object source ，Delegate callback，Object args，Boolean isSingleParameter，Delegate catchHandler）System.Windows.Threading.Dispatcher.WrappedInvoke（Delegate callback，Object args，Boolean isSingleParameter，Delegate catchHandler）вSystem.Windows.Threading.Dispatcher.WrappedInvoke（Delegate callback， Object args，Boolean isSingleParameter）System.Windows.Threading.Dispatcher.InvokeImpl（DispatcherPriority priority，TimeSpan timeout，Delegate方法，Object args，Boolean isSingleParameter）вS ystem.Windows.Threading.Dispatcher.Invoke（DispatcherPriority priority，Delegate方法，Object arg）•MS.Win32.HwndSubclass.SubclassWndProc（IntPtr hwnd，Int32 msg，IntPtr wParam，IntPtr lParam）•MS.Win32.UnsafeNativeMethods.CallWindowProc（IntPtr） wndProc，IntPtr hWnd，Int32 msg，IntPtr wParam，IntPtr lParam）•MS.Win32.HwndSubclass.DefWndProcWrapper（IntPtr hwnd，Int32 msg，IntPtr wParam，IntPtr lParam）•MS.Win32.UnsafeNativeMethods.CallWindowProc（IntPtr wndProc，IntPtr hWnd， Int32 msg，IntPtr wParam，IntPtr lParam）•MS.Win32.HwndSubclass.CallOldWindowProc（IntPtr oldWndProc，IntPtr hwnd，Int32 msg，IntPtr wParam，IntPtr lParam）•MS.Win32.HwndSubclass.SubclassWndProc（IntPtr hwnd，Int32 msg，IntPtr wParam ，IntPtr lParam）

在.net 4它工作正常