NullReferenceException: 未将对象引用设置到对象的实例。
StackTrace:
   在 System.Windows.Controls.Primitives.Popup.OnWindowResize(Object sender, AutoResizedEventArgs e)
   在 System.Windows.Interop.HwndSource.Resize(Size newSize)
   在 System.Windows.Interop.HwndSource.OnLayoutUpdated(Object obj, EventArgs args)
   在 System.Windows.ContextLayoutManager.fireLayoutUpdateEvent()
   在 System.Windows.ContextLayoutManager.UpdateLayout()
   在 System.Windows.ContextLayoutManager.UpdateLayoutCallback(Object arg)
   在 System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks()
   在 System.Windows.Media.MediaContext.RenderMessageHandlerCore(Object resizedCompositionTarget)
   在 System.Windows.Media.MediaContext.RenderMessageHandler(Object resizedCompositionTarget)
   在 System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   在 System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)

ArgumentException: “#5E81AC”不是 Setter 上“System.Windows.Controls.Panel.Background”属性的有效值。
--Message: “#5E81AC”不是 Setter 上“System.Windows.Controls.Panel.Background”属性的有效值。
StackTrace:
   在 System.Windows.Setter.Seal()
   在 System.Windows.SetterBaseCollection.Seal()
   在 System.Windows.TriggerBase.ProcessSettersCollection(SetterBaseCollection setters)
   在 System.Windows.Trigger.Seal()
   在 System.Windows.TriggerCollection.Seal()
   在 System.Windows.Style.Seal()
   在 System.Windows.StyleHelper.UpdateStyleCache(FrameworkElement fe, FrameworkContentElement fce, Style oldStyle, Style newStyle, Style& styleCache)
   在 System.Windows.FrameworkElement.OnStyleChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
   在 System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
   在 System.Windows.FrameworkElement.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
   在 System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args)
   在 System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
   在 System.Windows.DependencyObject.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal)
   在 System.Windows.Controls.ItemsControl.ApplyItemContainerStyle(DependencyObject container, Object item)
   在 System.Windows.Controls.ItemsControl.MS.Internal.Controls.IGeneratorHost.PrepareItemContainer(DependencyObject container, Object item)
   在 System.Windows.Controls.Panel.GenerateChildren()
   在 System.Windows.Controls.Panel.EnsureGenerator()
   在 System.Windows.Controls.Panel.get_InternalChildren()
   在 System.Windows.Controls.StackPanel.StackMeasureHelper(IStackMeasure measureElement, IStackMeasureScrollData scrollData, Size constraint)
   在 System.Windows.Controls.StackPanel.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint)
   在 System.Windows.Controls.ItemsPresenter.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint)
   在 System.Windows.Controls.ScrollContentPresenter.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV)
   在 System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV, Boolean& hasDesiredSizeUChanged)
   在 System.Windows.Controls.Grid.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.ScrollViewer.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Border.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Documents.AdornerDecorator.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Decorator.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Primitives.PopupRoot.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Interop.HwndSource.SetLayoutSize()
   在 System.Windows.Interop.HwndSource.set_RootVisualInternal(Visual value)
   在 System.Windows.Controls.Primitives.Popup.SetRootVisualToPopupRoot()
   在 System.Windows.Controls.Primitives.Popup.CreateWindow(Boolean asyncCall)
   在 System.Windows.Controls.Primitives.Popup.OnIsOpenChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
   在 System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
   在 System.Windows.FrameworkElement.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
   在 System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args)
   在 System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
   在 System.Windows.DependencyObject.InvalidateProperty(DependencyProperty dp, Boolean preserveCurrentValue)
   在 System.Windows.Data.BindingExpressionBase.Invalidate(Boolean isASubPropertyChange)
   在 System.Windows.Data.BindingExpression.TransferValue(Object newValue, Boolean isASubPropertyChange)
   在 MS.Internal.Data.PropertyPathWorker.UpdateSourceValueState(Int32 k, ICollectionView collectionView, Object newValue, Boolean isASubPropertyChange)
   在 MS.Internal.Data.PropertyPathWorker.OnDependencyPropertyChanged(DependencyObject d, DependencyProperty dp, Boolean isASubPropertyChange)
   在 System.Windows.Data.BindingExpression.HandlePropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   在 System.Windows.Data.BindingExpressionBase.OnPropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   在 System.Windows.Data.BindingExpression.OnPropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   在 System.Windows.DependentList.InvalidateDependents(DependencyObject source, DependencyPropertyChangedEventArgs sourceArgs)
   在 System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args)
   在 System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
   在 System.Windows.DependencyObject.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal)
   在 MS.Internal.Data.PropertyPathWorker.SetValue(Object item, Object value)
   在 System.Windows.Data.BindingExpression.UpdateSource(Object value)