wp7芒果中的DataTemplateSelector
我的应用程序中需要一个数据模板选择器。 我发现这个博客在7.0上运行得很好。 将项目升级到7.1后，设置模板时出现“未指定的错误”。 我试图将他们在博客上发布的示例项目升级到芒果，它仍然有效。 我不知道我做错了什么，因为看起来这个代码对于芒果来说是好的。 有什么建议？
public class ParameterTemplateSelector : DataTemplateSelector { public DataTemplate TextDataTemplate { get; set; } public DataTemplate NumberDataTemplate { get; set; } public DataTemplate DateDataTemplate { get; set; } public DataTemplate TimeDataTemplate { get; set; } public DataTemplate PictureDataTemplate { get; set; } public DataTemplate NonParamDataTemplate { get; set; } public override DataTemplate SelectTemplate(object item, DependencyObject container) { string type = ""; if (item is IParam) { IParam parameter = item as IParam; type = parameter.Type; } else if (item is KeyValue) { KeyValue k = item as KeyValue; type = k.Type; } switch (type) { case "String": return TextDataTemplate; case "Text": return TextDataTemplate; case "Number": return NumberDataTemplate; case "Date": return DateDataTemplate; case "Time": return TimeDataTemplate; case "Picture": return PictureDataTemplate; default: return TextDataTemplate; } } } public abstract class DataTemplateSelector : ContentControl { public virtual DataTemplate SelectTemplate(object item, DependencyObject container) { return null; } protected override void OnContentChanged(object oldContent, object newContent) { base.OnContentChanged(oldContent, newContent); ContentTemplate = SelectTemplate(newContent, this); } }
我得到的例外是：
System.Exception occurred Message=Unspecified error StackTrace: at MS.Internal.XcpImports.CheckHResult(UInt32 hr) at MS.Internal.XcpImports.FrameworkElement_MeasureOverride(FrameworkElement element, Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(IntPtr nativeTarget, Double inWidth, Double inHeight, Double& outWidth, Double& outHeight) at MS.Internal.XcpImports.MeasureOverrideNative(IntPtr element, Single inWidth, Single inHeight, Single& outWidth, Single& outHeight) at MS.Internal.XcpImports.FrameworkElement_MeasureOverride(FrameworkElement element, Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(IntPtr nativeTarget, Double inWidth, Double inHeight, Double& outWidth, Double& outHeight) at MS.Internal.XcpImports.MeasureNative(IntPtr element, Single inWidth, Single inHeight) at MS.Internal.XcpImports.UIElement_Measure(UIElement element, Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.VirtualizingStackPanel.MeasureChild(UIElement child, Size layoutSlotSize) at System.Windows.Controls.VirtualizingStackPanel.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureOverride(IntPtr nativeTarget, Double inWidth, Double inHeight, Double& outWidth, Double& outHeight) at MS.Internal.XcpImports.MeasureOverrideNative(IntPtr element, Single inWidth, Single inHeight, Single& outWidth, Single& outHeight) at MS.Internal.XcpImports.FrameworkElement_MeasureOverride(FrameworkElement element, Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(Size availableSize) at System.Windows.Controls.ScrollContentPresenter.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureOverride(IntPtr nativeTarget, Double inWidth, Double inHeight, Double& outWidth, Double& outHeight) at MS.Internal.XcpImports.MeasureNative(IntPtr element, Single inWidth, Single inHeight) at MS.Internal.XcpImports.UIElement_Measure(UIElement element, Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.ScrollViewer.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureOverride(IntPtr nativeTarget, Double inWidth, Double inHeight, Double& outWidth, Double& outHeight) at MS.Internal.XcpImports.MeasureOverrideNative(IntPtr element, Single inWidth, Single inHeight, Single& outWidth, Single& outHeight) at MS.Internal.XcpImports.FrameworkElement_MeasureOverride(FrameworkElement element, Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(IntPtr nativeTarget, Double inWidth, Double inHeight, Double& outWidth, Double& outHeight) at MS.Internal.XcpImports.MeasureOverrideNative(IntPtr element, Single inWidth, Single inHeight, Single& outWidth, Single& outHeight) at MS.Internal.XcpImports.FrameworkElement_MeasureOverride(FrameworkElement element, Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(IntPtr nativeTarget, Double inWidth, Double inHeight, Double& outWidth, Double& outHeight) at MS.Internal.XcpImports.MeasureOverrideNative(IntPtr element, Single inWidth, Single inHeight, Single& outWidth, Single& outHeight) at MS.Internal.XcpImports.FrameworkElement_MeasureOverride(FrameworkElement element, Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(Size availableSize) at Microsoft.Phone.Controls.PivotItem.MeasureOverride(Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(IntPtr nativeTarget, Double inWidth, Double inHeight, Double& outWidth, Double& outHeight) at MS.Internal.XcpImports.MeasureOverrideNative(IntPtr element, Single inWidth, Single inHeight, Single& outWidth, Single& outHeight) at MS.Internal.XcpImports.FrameworkElement_MeasureOverride(FrameworkElement element, Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(Size availableSize) at Microsoft.Phone.Controls.Pivot.MeasureOverride(Size availableSize) at System.Windows.FrameworkElement.MeasureOverride(IntPtr nativeTarget, Double inWidth, Double inHeight, Double& outWidth, Double& outHeight) at MS.Internal.XcpImports.UpdateLayoutNative(IntPtr element) at MS.Internal.XcpImports.UIElement_UpdateLayout(UIElement element) at System.Windows.UIElement.UpdateLayout() at Microsoft.Phone.Controls.Pivot.OnItemsChanged(NotifyCollectionChangedEventArgs e) at System.Windows.Controls.ItemsControl.OnItemCollectionChanged(Object sender, NotifyCollectionChangedEventArgs e) at System.Windows.Controls.ItemCollection.NotifyCollectionChanged(NotifyCollectionChangedEventArgs e) at System.Windows.Controls.ItemCollection.UpdateItemsSourceList(IEnumerable newItemsSource) at System.Windows.Controls.ItemsControl.ItemsSourceChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) at System.Windows.DependencyObject.RaisePropertyChangeNotifications(DependencyProperty dp, Object oldValue, Object newValue) at System.Windows.DependencyObject.UpdateEffectiveValue(DependencyProperty property, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, ValueOperation operation) at System.Windows.DependencyObject.RefreshExpression(DependencyProperty dp) at System.Windows.Data.BindingExpression.RefreshExpression() at System.Windows.Data.BindingExpression.SendDataToTarget() at System.Windows.Data.BindingExpression.SourceAcquired() at System.Windows.Data.BindingExpression.System.Windows.IDataContextChangedListener.OnDataContextChanged(Object sender, DataContextChangedEventArgs e) at System.Windows.Data.BindingExpression.DataContextChanged(Object sender, DataContextChangedEventArgs e) at System.Windows.FrameworkElement.OnDataContextChanged(DataContextChangedEventArgs e) at System.Windows.FrameworkElement.OnAncestorDataContextChanged(DataContextChangedEventArgs e) at System.Windows.FrameworkElement.NotifyDataContextChanged(DataContextChangedEventArgs e) at System.Windows.FrameworkElement.OnAncestorDataContextChanged(DataContextChangedEventArgs e) at System.Windows.FrameworkElement.NotifyDataContextChanged(DataContextChangedEventArgs e) at System.Windows.FrameworkElement.OnPropertyChanged(DependencyProperty dp) at System.Windows.DependencyObject.RaisePropertyChangeNotifications(DependencyProperty dp, Object oldValue, Object newValue) at System.Windows.DependencyObject.UpdateEffectiveValue(DependencyProperty property, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, ValueOperation operation) at System.Windows.DependencyObject.SetValueInternal(DependencyProperty dp, Object value, Boolean allowReadOnlySet) at System.Windows.DependencyObject.SetValueInternal(DependencyProperty dp, Object value) at System.Windows.DependencyObject.SetValue(DependencyProperty dp, Object value) at System.Windows.FrameworkElement.set_DataContext(Object value) at WPUserControls.ViewModel.ItemsTypeViewModel.AddItem(ItemInstance itemInstance) at WPUserControls.ViewModel.ItemsTypePageViewModel.AddNewItemInstance() at WPUserControls.Views.ItemsTypePageView.AddItem() at WPUserControls.Views.ItemsTypePageView.addIcon_Click(Object sender, EventArgs e) at Microsoft.Phone.Shell.ApplicationBarItemContainer.FireEventHandler(EventHandler handler, Object sender, EventArgs args) at Microsoft.Phone.Shell.ApplicationBarIconButton.ClickEvent() at Microsoft.Phone.Shell.ApplicationBarIconButtonContainer.ClickEvent() at Microsoft.Phone.Shell.ApplicationBar.OnCommand(UInt32 idCommand) at Microsoft.Phone.Shell.Interop.NativeCallbackInteropWrapper.OnCommand(UInt32 idCommand)
我无法确定问题，但似乎问题不在你的模板选择器本身，而是模板中的一个。
尝试将它们中的每一个减少到基本最小值（不同颜色的文本框）或其他东西，看它是否有效，还尝试添加其他类型的项目，看看会发生什么。
一旦我安装了sdk RC，就修好了！ 我想这是一个MS bug。