WPF Freezable漏洞的解决方法？

Question

我最近遇到了一个非常糟糕的WPF错误.我认为它与Microsoft Connect上的这个错误相同.

我们的应用程序使用Visual Studio 2010定位.NET 4.0 Client Profile.

基本上,当ViewModel触发对任何导致项目在ItemsControl中移动的属性或集合的更改时,可能会抛出下面的异常.它并不总是发生,似乎是基于不同时间的不同触发器而发生的.在启动应用程序后不久,它似乎更有可能.如果您可以使用它几分钟而不会遇到异常,那么您可能永远不会在该应用程序实例期间遇到它.

就像Connect错误报告一样,我正在使用来自a的{DynamicResource key}加载SolidColorBrushes ResourceDictionary.一些字典是手动加载的(用于支持).我尝试手动冻结这些词典中的所有内容,但似乎没有帮助.

最近,当我向UserControl主窗口添加了几个s并将其中的ItemsControls绑定到ObservableCollections 时,异常变得更加频繁.以前,我只看到50次中的1次异常,但现在我看到它使用该程序的5次中有4次.

有没有人有任何解决方法的想法？Connect错误表明这可能会在下一个.NET版本中修复(无论何时),但是这个错误使我们的应用程序现在基本上无法使用.

    System.InvalidOperationException: Specified value of type 'System.Windows.Media.SolidColorBrush' must have IsFrozen set to false to modify.
       at System.Windows.Freezable.WritePreamble()
       at System.Windows.Freezable.remove_Changed(EventHandler value)
       at System.Windows.ResourceReferenceExpression.ResourceReferenceExpressionWeakContainer.RemoveChangedHandler()
       at System.Windows.ResourceReferenceExpression.ResourceReferenceExpressionWeakContainer.InvalidateTargetSubProperty(Object sender, EventArgs args)
       at System.Windows.Freezable.FireChanged()
       at System.Windows.Freezable.Freeze(Boolean isChecking)
       at System.Windows.Freezable.Freeze()
       at System.Windows.Freezable.System.Windows.ISealable.Seal()
       at System.Windows.StyleHelper.SealIfSealable(Object value)
       at System.Windows.StyleHelper.GetChildValueHelper(UncommonField`1 dataField, ItemStructList`1& valueLookupList, DependencyProperty dp, DependencyObject container, FrameworkObject child, Int32 childIndex, Boolean styleLookup, EffectiveValueEntry& entry, ValueLookupType& sourceType, FrameworkElementFactory templateRoot)
       at System.Windows.StyleHelper.GetChildValue(UncommonField`1 dataField, DependencyObject container, Int32 childIndex, FrameworkObject child, DependencyProperty dp, FrugalStructList`1& childRecordFromChildIndex, EffectiveValueEntry& entry, ValueLookupType& sourceType, FrameworkElementFactory templateRoot)
       at System.Windows.StyleHelper.GetValueFromTemplatedParent(DependencyObject container, Int32 childIndex, FrameworkObject child, DependencyProperty dp, FrugalStructList`1& childRecordFromChildIndex, FrameworkElementFactory templateRoot, EffectiveValueEntry& entry)
       at System.Windows.FrameworkElement.GetValueFromTemplatedParent(DependencyProperty dp, EffectiveValueEntry& entry)
       at System.Windows.FrameworkElement.GetRawValue(DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry& entry)
       at System.Windows.FrameworkElement.EvaluateBaseValueCore(DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry& newEntry)
       at System.Windows.DependencyObject.EvaluateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry newEntry, OperationType operationType)
       at System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
       at System.Windows.DependencyObject.InvalidateProperty(DependencyProperty dp)
       at System.Windows.StyleHelper.InvalidateResourceDependentsForChild(DependencyObject container, DependencyObject child, Int32 childIndex, ResourcesChangeInfo info, FrameworkTemplate parentTemplate)
       at System.Windows.TreeWalkHelper.InvalidateStyleAndReferences(DependencyObject d, ResourcesChangeInfo info, Boolean containsTypeOfKey)
       at System.Windows.TreeWalkHelper.OnResourcesChanged(DependencyObject d, ResourcesChangeInfo info, Boolean raiseResourceChangedEvent)
       at System.Windows.FrameworkElement.OnAncestorChangedInternal(TreeChangeInfo parentTreeState)
       at System.Windows.TreeWalkHelper.OnAncestorChanged(DependencyObject d, TreeChangeInfo info)
       at System.Windows.DescendentsWalker`1._VisitNode(DependencyObject d)
       at MS.Internal.PrePostDescendentsWalker`1._VisitNode(DependencyObject d)
       at System.Windows.DescendentsWalker`1.VisitNode(FrameworkElement fe)
       at System.Windows.DescendentsWalker`1.VisitNode(DependencyObject d)
       at System.Windows.DescendentsWalker`1.WalkFrameworkElementLogicalThenVisualChildren(FrameworkElement feParent, Boolean hasLogicalChildren)
       at System.Windows.DescendentsWalker`1.IterateChildren(DependencyObject d)
       at System.Windows.DescendentsWalker`1.StartWalk(DependencyObject startNode, Boolean skipStartNode)
       at MS.Internal.PrePostDescendentsWalker`1.StartWalk(DependencyObject startNode, Boolean skipStartNode)
       at System.Windows.TreeWalkHelper.InvalidateOnTreeChange(FrameworkElement fe, FrameworkContentElement fce, DependencyObject parent, Boolean isAddOperation)
       at System.Windows.FrameworkElement.OnVisualParentChanged(DependencyObject oldParent)
       at System.Windows.Media.Visual.FireOnVisualParentChanged(DependencyObject oldParent)
       at System.Windows.Media.Visual.RemoveVisualChild(Visual child)
       at System.Windows.Media.VisualCollection.DisconnectChild(Int32 index)
       at System.Windows.Media.VisualCollection.Clear()
       at System.Windows.Controls.UIElementCollection.ClearInternal()
       at System.Windows.Controls.Panel.ClearChildren()
       at System.Windows.Controls.Panel.OnItemsChangedInternal(Object sender, ItemsChangedEventArgs args)
       at System.Windows.Controls.Panel.OnItemsChanged(Object sender, ItemsChangedEventArgs args)
       at System.Windows.Controls.ItemContainerGenerator.OnRefresh()
       at System.Windows.Controls.ItemContainerGenerator.OnCollectionChanged(Object sender, NotifyCollectionChangedEventArgs args)
       at System.Windows.Controls.ItemContainerGenerator.System.Windows.IWeakEventListener.ReceiveWeakEvent(Type managerType, Object sender, EventArgs e)
       at System.Windows.WeakEventManager.DeliverEventToList(Object sender, EventArgs args, ListenerList list)
       at System.Windows.WeakEventManager.DeliverEvent(Object sender, EventArgs args)
       at System.Collections.Specialized.CollectionChangedEventManager.OnCollectionChanged(Object sender, NotifyCollectionChangedEventArgs args)
       at System.Collections.Specialized.NotifyCollectionChangedEventHandler.Invoke(Object sender, NotifyCollectionChangedEventArgs e)
       at System.Windows.Data.CollectionView.OnCollectionChanged(NotifyCollectionChangedEventArgs args)
       at System.Windows.Controls.ItemCollection.System.Windows.IWeakEventListener.ReceiveWeakEvent(Type managerType, Object sender, EventArgs e)
       at System.Windows.WeakEventManager.DeliverEventToList(Object sender, EventArgs args, ListenerList list)
       at System.Windows.WeakEventManager.DeliverEvent(Object sender, EventArgs args)
       at System.Collections.Specialized.CollectionChangedEventManager.OnCollectionChanged(Object sender, NotifyCollectionChangedEventArgs args)
       at System.Windows.Data.CollectionView.OnCollectionChanged(NotifyCollectionChangedEventArgs args)
       at System.Windows.Data.ListCollectionView.RefreshOverride()
       at System.Windows.Data.CollectionView.Refresh()
       at System.Windows.Data.CollectionView.EndDefer()
       at System.Windows.Data.CollectionView.DeferHelper.Dispose()
       at System.Windows.Controls.ItemCollection.SetCollectionView(CollectionView view)
       at System.Windows.Controls.ItemCollection.SetItemsSource(IEnumerable value)
       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.DependencyObject.InvalidateProperty(DependencyProperty dp)
       at System.Windows.Data.BindingExpressionBase.Invalidate(Boolean isASubPropertyChange)
       at System.Windows.Data.BindingExpression.TransferValue(Object newValue, Boolean isASubPropertyChange)
       at System.Windows.Data.BindingExpression.ScheduleTransfer(Boolean isASubPropertyChange)
       at MS.Internal.Data.ClrBindingWorker.NewValueAvailable(Boolean dependencySourcesChanged, Boolean initialValue, Boolean isASubPropertyChange)
       at MS.Internal.Data.PropertyPathWorker.UpdateSourceValueState(Int32 k, ICollectionView collectionView, Object newValue, Boolean isASubPropertyChange)
       at MS.Internal.Data.ClrBindingWorker.OnSourcePropertyChanged(Object o, String propName)
       at MS.Internal.Data.PropertyPathWorker.System.Windows.IWeakEventListener.ReceiveWeakEvent(Type managerType, Object sender, EventArgs e)
       at System.Windows.WeakEventManager.DeliverEventToList(Object sender, EventArgs args, ListenerList list)
       at System.ComponentModel.PropertyChangedEventManager.OnPropertyChanged(Object sender, PropertyChangedEventArgs args)
       at ***.ViewModelBase.OnPropertyChanged(String name) in c:\***\ViewModelBase.cs:line 17
    .....

编辑:我们也试图简单地抑制InvalidOperationException我们的ViewModel基类的PropertyChanged事件中抛出的任何内容.这似乎减少异常的数目了几分,但现在我们只是打他们ObservableCollection的CollectionChanged活动.

Answer 1

要解决此.net错误,请将代码中的所有纯色画笔更改为可冻结.例如

<SolidColorBrush x:Key="WindowBackground" Color="Black" />

应改为:

<SolidColorBrush po:Freeze="True" x:Key="WindowBackground" Color="Black" />. 

有关更详细的说明,请参阅此处:如何从FreeZable派生WPF对象在XAML中冻结？.