System.InvalidOperationException: '无法在...范围内内找到“PART_VerticalScrollBar”名称。'

[cuiliang]

完整报错消息：无法在“System.Windows.Controls.ControlTemplate”的名称范围内内找到“PART_VerticalScrollBar”名称

在符合下面的条件时，会触发异常： (1) ComboBox 本身或父控件通过hc:ScrollViewerAttach.AutoHide="False" 禁止滚动条自动隐藏。 (2) ComboBox 的选项数量足够多，让滚动条出现。 (3) 通过Style动态触发IsEditable属性的变化： ( 这里的目的是实现点击控件的时候变为IsEditable=true，选择选项之后取消IsEditable状态。）

<ComboBox ItemsSource="{Binding DataList}" Margin="0,16,0,0" SelectedIndex="0"
                          IsTextSearchEnabled="True"
                          hc:ScrollViewerAttach.AutoHide="False"
                          StaysOpenOnEdit="True">
                    <ComboBox.Style>
                        <Style TargetType="ComboBox" BasedOn="{StaticResource ComboBoxBaseStyle}">
                            <Style.Triggers>
                                <Trigger Property="IsKeyboardFocusWithin" Value="True">
                                    <Setter Property="IsEditable" Value="True" />
                                </Trigger>
                                <Trigger Property="IsDropDownOpen" Value="False">
                                    <Setter Property="IsEditable" Value="False" />
                                </Trigger>
                            </Style.Triggers>
                        </Style>
                    </ComboBox.Style>
                </ComboBox>

效果：

StackTrace

System.InvalidOperationException
  HResult=0x80131509
  Message=无法在“System.Windows.Controls.ControlTemplate”的名称范围内内找到“PART_VerticalScrollBar”名称。
  Source=PresentationFramework
  StackTrace:
   at System.Windows.Media.Animation.Storyboard.ResolveTargetName(String targetName, INameScope nameScope, DependencyObject element)
   at System.Windows.Media.Animation.Storyboard.ClockTreeWalkRecursive(Clock currentClock, DependencyObject containingObject, INameScope nameScope, DependencyObject parentObject, String parentObjectName, PropertyPath parentPropertyPath, HandoffBehavior handoffBehavior, HybridDictionary clockMappings, Int64 layer)
   at System.Windows.Media.Animation.Storyboard.ClockTreeWalkRecursive(Clock currentClock, DependencyObject containingObject, INameScope nameScope, DependencyObject parentObject, String parentObjectName, PropertyPath parentPropertyPath, HandoffBehavior handoffBehavior, HybridDictionary clockMappings, Int64 layer)
   at System.Windows.Media.Animation.Storyboard.BeginCommon(DependencyObject containingObject, INameScope nameScope, HandoffBehavior handoffBehavior, Boolean isControllable, Int64 layer)
   at System.Windows.Media.Animation.BeginStoryboard.Begin(DependencyObject targetObject, INameScope nameScope, Int64 layer)
   at System.Windows.Media.Animation.BeginStoryboard.Invoke(FrameworkElement fe, FrameworkContentElement fce, Style targetStyle, FrameworkTemplate frameworkTemplate, Int64 layer)
   at System.Windows.StyleHelper.InvokeActions(TriggerBase triggerBase, DependencyObject triggerContainer, TriggerActionCollection actions, Style style, FrameworkTemplate frameworkTemplate)
   at System.Windows.StyleHelper.InvokeEnterOrExitActions(TriggerBase triggerBase, Boolean oldState, Boolean newState, DependencyObject triggerContainer, Style style, FrameworkTemplate frameworkTemplate)
   at System.Windows.StyleHelper.InvokePropertyTriggerActions(TriggerBase triggerBase, DependencyObject triggerContainer, DependencyProperty changedProperty, DependencyPropertyChangedEventArgs changedArgs, Int32 sourceChildIndex, Style style, FrameworkTemplate frameworkTemplate)
   at System.Windows.StyleHelper.OnTriggerSourcePropertyInvalidated(Style ownerStyle, FrameworkTemplate frameworkTemplate, DependencyObject container, DependencyProperty dp, DependencyPropertyChangedEventArgs changedArgs, Boolean invalidateOnlyContainer, FrugalStructList`1& triggerSourceRecordFromChildIndex, FrugalMap& propertyTriggersWithActions, Int32 sourceChildIndex)
   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.ClearValueCommon(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata)
   at System.Windows.DependencyObject.ClearValue(DependencyPropertyKey key)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.OnOriginValueChanged(DependencyObject oldOrigin, DependencyObject newOrigin, IList`1 otherOrigins, DeferredElementTreeState& oldTreeState, Action`2 originChangedAction)
   at System.Windows.Input.MouseDevice.ChangeMouseOver(IInputElement mouseOver, Int32 timestamp)
   at System.Windows.Input.MouseDevice.PreNotifyInput(Object sender, NotifyInputEventArgs e)
   at System.Windows.Input.InputManager.ProcessStagingArea()
   at System.Windows.Input.MouseDevice.Synchronize()
   at System.Windows.Input.Mouse.Synchronize()
   at System.Windows.Controls.Primitives.Track.OnIsEnabledChanged(DependencyObject d, 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, Boolean preserveCurrentValue)
   at System.Windows.StyleHelper.InvalidatePropertiesOnTemplateNode(DependencyObject container, FrameworkObject child, Int32 childIndex, FrugalStructList`1& childRecordFromChildIndex, Boolean isDetach, FrameworkElementFactory templateRoot)
   at System.Windows.StyleHelper.ClearTemplateChain(HybridDictionary[] instanceData, FrameworkElement feContainer, FrameworkContentElement fceContainer, List`1 templateChain, FrameworkTemplate oldFrameworkTemplate)
   at System.Windows.StyleHelper.ClearGeneratedSubTree(HybridDictionary[] instanceData, FrameworkElement feContainer, FrameworkContentElement fceContainer, FrameworkTemplate oldFrameworkTemplate)
   at System.Windows.StyleHelper.DoTemplateInvalidations(FrameworkElement feContainer, FrameworkTemplate oldFrameworkTemplate)
   at System.Windows.Controls.Control.OnTemplateChanged(DependencyObject d, 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, Boolean preserveCurrentValue)
   at System.Windows.StyleHelper.InvalidateContainerDependents(DependencyObject container, FrugalStructList`1& exclusionContainerDependents, FrugalStructList`1& 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.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, Boolean preserveCurrentValue)
   at System.Windows.StyleHelper.ClearTemplateChain(HybridDictionary[] instanceData, FrameworkElement feContainer, FrameworkContentElement fceContainer, List`1 templateChain, FrameworkTemplate oldFrameworkTemplate)
   at System.Windows.StyleHelper.ClearGeneratedSubTree(HybridDictionary[] instanceData, FrameworkElement feContainer, FrameworkContentElement fceContainer, FrameworkTemplate oldFrameworkTemplate)
   at System.Windows.StyleHelper.DoTemplateInvalidations(FrameworkElement feContainer, FrameworkTemplate oldFrameworkTemplate)
   at System.Windows.Controls.Control.OnTemplateChanged(DependencyObject d, 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, Boolean preserveCurrentValue)
   at System.Windows.StyleHelper.InvalidateDependents(Style ownerStyle, FrameworkTemplate frameworkTemplate, DependencyObject container, DependencyProperty dp, FrugalStructList`1& dependents, Boolean invalidateOnlyContainer)
   at System.Windows.StyleHelper.OnTriggerSourcePropertyInvalidated(Style ownerStyle, FrameworkTemplate frameworkTemplate, DependencyObject container, DependencyProperty dp, DependencyPropertyChangedEventArgs changedArgs, Boolean invalidateOnlyContainer, FrugalStructList`1& triggerSourceRecordFromChildIndex, FrugalMap& propertyTriggersWithActions, Int32 sourceChildIndex)
   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.TreeWalkHelper.InvalidateTreeDependentProperty(TreeChangeInfo info, DependencyObject d, FrameworkObject& fo, DependencyProperty dp, FrameworkPropertyMetadata fMetadata, Style selfStyle, Style selfThemeStyle, ChildRecord& childRecord, Boolean isChildRecordValid, Boolean hasStyleChanged, Boolean isSelfInheritanceParent, Boolean wasSelfInheritanceParent)
   at System.Windows.TreeWalkHelper.InvalidateTreeDependentProperties(TreeChangeInfo info, FrameworkElement fe, FrameworkContentElement fce, Style selfStyle, Style selfThemeStyle, ChildRecord& childRecord, Boolean isChildRecordValid, Boolean hasStyleChanged, Boolean isSelfInheritanceParent, Boolean wasSelfInheritanceParent)
   at System.Windows.FrameworkElement.InvalidateTreeDependentProperties(TreeChangeInfo parentTreeState, Boolean isSelfInheritanceParent, Boolean wasSelfInheritanceParent)
   at System.Windows.FrameworkElement.OnAncestorChangedInternal(TreeChangeInfo parentTreeState)
   at System.Windows.TreeWalkHelper.OnAncestorChanged(DependencyObject d, TreeChangeInfo info, Boolean visitedViaVisualTree)
   at MS.Internal.PrePostDescendentsWalker`1._VisitNode(DependencyObject d, Boolean visitedViaVisualTree)
   at System.Windows.DescendentsWalker`1.WalkFrameworkElementLogicalThenVisualChildren(FrameworkElement feParent, Boolean hasLogicalChildren)
   at System.Windows.DescendentsWalker`1.IterateChildren(DependencyObject d)
   at MS.Internal.PrePostDescendentsWalker`1._VisitNode(DependencyObject d, Boolean visitedViaVisualTree)
   at System.Windows.DescendentsWalker`1.WalkLogicalChildren(FrameworkElement feParent, FrameworkContentElement fceParent, IEnumerator logicalChildren)
   at System.Windows.DescendentsWalker`1.WalkFrameworkElementLogicalThenVisualChildren(FrameworkElement feParent, Boolean hasLogicalChildren)
   at System.Windows.DescendentsWalker`1.IterateChildren(DependencyObject d)
   at MS.Internal.PrePostDescendentsWalker`1._VisitNode(DependencyObject d, Boolean visitedViaVisualTree)
   at System.Windows.DescendentsWalker`1.WalkLogicalChildren(FrameworkElement feParent, FrameworkContentElement fceParent, IEnumerator logicalChildren)
   at System.Windows.DescendentsWalker`1.WalkFrameworkElementLogicalThenVisualChildren(FrameworkElement feParent, Boolean hasLogicalChildren)
   at System.Windows.DescendentsWalker`1.IterateChildren(DependencyObject d)
   at MS.Internal.PrePostDescendentsWalker`1._VisitNode(DependencyObject d, Boolean visitedViaVisualTree)
   at System.Windows.DescendentsWalker`1.WalkFrameworkElementLogicalThenVisualChildren(FrameworkElement feParent, Boolean hasLogicalChildren)
   at System.Windows.DescendentsWalker`1.IterateChildren(DependencyObject d)
   at MS.Internal.PrePostDescendentsWalker`1._VisitNode(DependencyObject d, Boolean visitedViaVisualTree)
   at System.Windows.DescendentsWalker`1.WalkLogicalChildren(FrameworkElement feParent, FrameworkContentElement fceParent, IEnumerator logicalChildren)
   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.ChangeLogicalParent(DependencyObject newParent)
   at System.Windows.FrameworkElement.RemoveLogicalChild(Object child)
   at System.Windows.Controls.Primitives.Popup.OnChildChanged(DependencyObject d, 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, Boolean preserveCurrentValue)
   at System.Windows.StyleHelper.ClearTemplateChain(HybridDictionary[] instanceData, FrameworkElement feContainer, FrameworkContentElement fceContainer, List`1 templateChain, FrameworkTemplate oldFrameworkTemplate)
   at System.Windows.StyleHelper.ClearGeneratedSubTree(HybridDictionary[] instanceData, FrameworkElement feContainer, FrameworkContentElement fceContainer, FrameworkTemplate oldFrameworkTemplate)
   at System.Windows.StyleHelper.DoTemplateInvalidations(FrameworkElement feContainer, FrameworkTemplate oldFrameworkTemplate)
   at System.Windows.Controls.Control.OnTemplateChanged(DependencyObject d, 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, Boolean preserveCurrentValue)
   at System.Windows.StyleHelper.InvalidateDependents(Style ownerStyle, FrameworkTemplate frameworkTemplate, DependencyObject container, DependencyProperty dp, FrugalStructList`1& dependents, Boolean invalidateOnlyContainer)
   at System.Windows.StyleHelper.OnTriggerSourcePropertyInvalidated(Style ownerStyle, FrameworkTemplate frameworkTemplate, DependencyObject container, DependencyProperty dp, DependencyPropertyChangedEventArgs changedArgs, Boolean invalidateOnlyContainer, FrugalStructList`1& triggerSourceRecordFromChildIndex, FrugalMap& propertyTriggersWithActions, Int32 sourceChildIndex)
   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, Boolean preserveCurrentValue)
   at System.Windows.StyleHelper.InvalidateDependents(Style ownerStyle, FrameworkTemplate frameworkTemplate, DependencyObject container, DependencyProperty dp, FrugalStructList`1& dependents, Boolean invalidateOnlyContainer)
   at System.Windows.StyleHelper.OnTriggerSourcePropertyInvalidated(Style ownerStyle, FrameworkTemplate frameworkTemplate, DependencyObject container, DependencyProperty dp, DependencyPropertyChangedEventArgs changedArgs, Boolean invalidateOnlyContainer, FrugalStructList`1& triggerSourceRecordFromChildIndex, FrugalMap& propertyTriggersWithActions, Int32 sourceChildIndex)
   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.DependencyObject.SetCurrentValueInternal(DependencyProperty dp, Object value)
   at System.Windows.Controls.ComboBox.Close()
   at System.Windows.Controls.ComboBox.NotifyComboBoxItemMouseUp(ComboBoxItem comboBoxItem)
   at System.Windows.Controls.ComboBoxItem.OnMouseLeftButtonUp(MouseButtonEventArgs e)
   at System.Windows.UIElement.OnMouseLeftButtonUpThunk(Object sender, 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.UIElement.OnMouseUpThunk(Object sender, 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.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 System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.Dispatcher.LegacyInvokeImpl(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.Threading.Dispatcher.PushFrame(DispatcherFrame frame)
   at System.Windows.Threading.Dispatcher.Run()
   at System.Windows.Application.RunDispatcher(Object ignore)
   at System.Windows.Application.RunInternal(Window window)
   at System.Windows.Application.Run()
   at HandyControlDemo.App.Main()

[cuiliang]

临时修改的复现代码。根目录bin_net472里有编译好的。点截图里的位置就会崩溃了。 https://wwr.lanzoui.com/iWv1Vu1ucad

[cuiliang]

@NaBian 刚下载最新代码测试了一下。demo需要两处修改来复现： 1） NativeComboBoxDemoCtl.xaml 里第二个ComboBox

<UserControl x:Class="HandyControlDemo.UserControl.NativeComboBoxDemoCtl"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:hc="https://handyorg.github.io/handycontrol"
             xmlns:langs="clr-namespace:HandyControlDemo.Properties.Langs"
             xmlns:ex="clr-namespace:HandyControlDemo.Tools.Extension"
             DataContext="{Binding ComboBoxDemo,Source={StaticResource Locator}}"
             Background="{DynamicResource RegionBrush}">
    <hc:TransitioningContentControl>
        <ScrollViewer>
            <StackPanel Margin="32">
                <ComboBox hc:DropDownElement.ConsistentWidth="False" ItemsSource="{Binding DataList}" SelectedIndex="0"/>
                <ComboBox ItemsSource="{Binding DataList}" Margin="0,16,0,0"
                          IsTextSearchEnabled="True"
                          hc:ScrollViewerAttach.AutoHide="False"
                          StaysOpenOnEdit="True">
                    <ComboBox.Style>
                        <Style TargetType="ComboBox" BasedOn="{StaticResource ComboBoxBaseStyle}">
                            <Style.Triggers>
                                <Trigger Property="IsKeyboardFocusWithin" Value="True">
                                    <Setter Property="IsEditable" Value="True" />
                                </Trigger>
                                <Trigger Property="IsDropDownOpen" Value="False">
                                    <Setter Property="IsEditable" Value="False" />
                                </Trigger>
                            </Style.Triggers>
                        </Style>
                    </ComboBox.Style>
                </ComboBox>
                <ComboBox ItemsSource="{Binding DataList}" SelectedIndex="0" Margin="0,16,0,0" IsEditable="True"/>

                <ComboBox hc:DropDownElement.ConsistentWidth="False" ItemsSource="{Binding DataList}" SelectedIndex="0" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr1}}" Style="{StaticResource ComboBoxExtend}" Margin="0,32,0,0" Text="{ex:Lang Key={x:Static langs:LangKeys.ContentDemoStr}}"/>
                <ComboBox ItemsSource="{Binding DataList}" hc:InfoElement.Placeholder="{ex:Lang Key={x:Static langs:LangKeys.PlsEnterContent}}" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr2}}" Style="{StaticResource ComboBoxExtend}" hc:InfoElement.Necessary="True" hc:InfoElement.Symbol="*" Margin="0,16,0,0"/>
                <ComboBox ItemsSource="{Binding DataList}" IsEditable="True" SelectedIndex="0" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr1}}" Style="{StaticResource ComboBoxExtend}" Margin="0,16,0,0" Text="{ex:Lang Key={x:Static langs:LangKeys.ContentDemoStr}}"/>
                <ComboBox ItemsSource="{Binding DataList}" IsEditable="True" hc:InfoElement.Placeholder="{ex:Lang Key={x:Static langs:LangKeys.PlsEnterContent}}" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr2}}" Style="{StaticResource ComboBoxExtend}" hc:InfoElement.Necessary="True" Margin="0,16,0,0"/>

                <ComboBox ItemsSource="{Binding DataList}" Width="380" hc:InfoElement.TitleWidth="140" hc:InfoElement.TitlePlacement="Left" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr3}}" Style="{StaticResource ComboBoxExtend}" Margin="0,32,0,0" Text="{ex:Lang Key={x:Static langs:LangKeys.ContentDemoStr}}"/>
                <ComboBox ItemsSource="{Binding DataList}" Width="380" hc:InfoElement.TitleWidth="140" hc:InfoElement.Placeholder="{ex:Lang Key={x:Static langs:LangKeys.PlsEnterContent}}" hc:InfoElement.TitlePlacement="Left" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr3}}" hc:InfoElement.Necessary="True" Style="{StaticResource ComboBoxExtend}" Margin="0,16,0,0"/>
                <ComboBox ItemsSource="{Binding DataList}" IsEditable="True" Width="380" hc:InfoElement.TitleWidth="140" hc:InfoElement.TitlePlacement="Left" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr3}}" Style="{StaticResource ComboBoxExtend}" Margin="0,16,0,0" Text="{ex:Lang Key={x:Static langs:LangKeys.ContentDemoStr}}"/>
                <ComboBox ItemsSource="{Binding DataList}" IsEditable="True" Width="380" hc:InfoElement.TitleWidth="140" hc:InfoElement.Placeholder="{ex:Lang Key={x:Static langs:LangKeys.PlsEnterContent}}" hc:InfoElement.TitlePlacement="Left" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr3}}" hc:InfoElement.Necessary="True" Style="{StaticResource ComboBoxExtend}" Margin="0,16,0,0"/>
            </StackPanel>
        </ScrollViewer>
    </hc:TransitioningContentControl>
</UserControl>

2） ComboBoxDemoViewModel.cs 108行， for (var i = 1; i <= 9; i++) 改为for (var i = 1; i <= 29; i++) 使得滚动条出现。

internal List<string> GetComboBoxDemoDataList()
        {
            var converter = new StringRepeatConverter();
            var list = new List<string>();
            for (var i = 1; i <= 29; i++)
            {
                list.Add($"{converter.Convert(Lang.Text, null, i, CultureInfo.CurrentCulture)}{i}");
            }

            return list;
        }

[MickeyJson]

我也遇到了这个问题