WPF Crash not in our code

0
votes

Does anyone know how to solve a crash in WPF where the call stack is completely in windows code.

Following is the call stack...

6/26/2014 3:29:05 PM: [FATAL] System.InvalidOperationException: Specified element is already the logical child of another element. Disconnect it first. at System.Windows.FrameworkElement.ChangeLogicalParent(DependencyObject newParent) at System.Windows.FrameworkElement.AddLogicalChild(Object child) at System.Windows.Controls.ContentControl.OnContentChanged(Object oldContent, Object newContent) at System.Windows.Controls.TabItem.OnContentChanged(Object oldContent, Object newContent) at System.Windows.Controls.ContentControl.OnContentChanged(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.StyleHelper.ApplyStyleOrTemplateValue(FrameworkObject fo, DependencyProperty dp) at System.Windows.StyleHelper.InvalidateContainerDependents(DependencyObject container, FrugalStructList1& exclusionContainerDependents, FrugalStructList1& oldContainerDependents, FrugalStructList`1& newContainerDependents) at System.Windows.StyleHelper.DoStyleInvalidations(FrameworkElement fe, FrameworkContentElement fce, Style oldStyle, Style newStyle) at System.Windows.StyleHelper.UpdateStyleCache(FrameworkElement fe, FrameworkContentElement fce, Style oldStyle, Style newStyle, Style& styleCache) at System.Windows.FrameworkElement.OnStyleChanged(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.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal) at System.Windows.Controls.ItemsControl.ApplyItemContainerStyle(DependencyObject container, Object item) at System.Windows.Controls.ItemsControl.MS.Internal.Controls.IGeneratorHost.PrepareItemContainer(DependencyObject container, Object item) at System.Windows.Controls.ItemContainerGenerator.System.Windows.Controls.Primitives.IItemContainerGenerator.PrepareItemContainer(DependencyObject container) at System.Windows.Controls.Panel.GenerateChildren() 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.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.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.ContextLayoutManager.UpdateLayoutCallback(Object arg) at System.Windows.Media.MediaContext.InvokeOnRenderCallback.DoWork() at System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks() at System.Windows.Media.MediaContext.RenderMessageHandlerCore(Object resizedCompositionTarget) at System.Windows.Media.MediaContext.RenderMessageHandler(Object resizedCompositionTarget) 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)

1
wpfcrash
It is a problem in your code. You're either messing with the Visual Tree in procedural code, which is really bad, or there's a XAML related issue where you're putting UI elements inside each other in a wrong way. Try to isolate the XAML what's being loaded at the moment of the exception, or try using PresentationTraceSources to debug XAML-related stuff. – Federico Berasategui
I didn't think it wasn't a problem in my code, just trying to figure out what is causing it... – Steve Graber
Messing with the visual tree isn't necessarily bad, it's just more complicated and higher risk. If you want to build complex controls and harness the most powerful aspects of WPF (including ui virtualization) you "have" to touch the visual tree. – Josh G
@HighCore, if you want to be helpful instead of demeaning, maybe clarify how to use the PresentationTraceSources to debug. I'm not familiar with that. – Josh G

1 Answers

1
votes

You're getting this error because you are trying to set a control (Visual) as the child of another Visual without first removing it from the visual tree. A Visual can never be in the visual tree in two places.

The difficult part is going to be tracking down what Visual is being inserted into the tree twice. You're going to have a really hard time catching it in the debugger (think nearly impossible), so you'll have to try some more creative debugging methods. If you can reproduce the problem consistently, maybe try stripping Visuals out one at a time and see which Visual is causing the problem that way. If you have some custom controls that are working with some lower level visual tree functionality, these are going to be highly suspect. Take a look at them first.