我在创建xaml控件时遇到问题。我正在用通用应用程序在VS 2015中编写新项目。我要创建网格。在此网格中,我想有一个按钮。在模型中,我指定列(级别)和行。这是我的代码:
<ItemsControl Grid.Row="1" ItemsSource="{Binding Path=TechnologyList}"> <ItemsControl.ItemsPanel> <ItemsPanelTemplate> <Grid> <Grid.RowDefinitions> <RowDefinition Height="10*"/> <RowDefinition Height="10*"/> <RowDefinition Height="10*"/> <RowDefinition Height="10*"/> <RowDefinition Height="10*"/> <RowDefinition Height="10*"/> <RowDefinition Height="10*"/> <RowDefinition Height="10*"/> <RowDefinition Height="10*"/> <RowDefinition Height="10*"/> </Grid.RowDefinitions> <Grid.ColumnDefinitions> <ColumnDefinition Width="14*"/> <ColumnDefinition Width="14*"/> <ColumnDefinition Width="14*"/> <ColumnDefinition Width="14*"/> <ColumnDefinition Width="14*"/> <ColumnDefinition Width="14*"/> <ColumnDefinition Width="14*"/> </Grid.ColumnDefinitions> </Grid> </ItemsPanelTemplate> </ItemsControl.ItemsPanel> <ItemsControl.ItemContainerStyle> <Style TargetType="Control"> <Setter Property="Grid.Column" Value="{Binding Level}" /> <Setter Property="Grid.Row" Value="{Binding Row}" /> </Style> </ItemsControl.ItemContainerStyle> <ItemsControl.ItemTemplate> <DataTemplate> <Button Content="{Binding Name}"/> </DataTemplate> </ItemsControl.ItemTemplate> </ItemsControl>
我在行中收到错误<Setter Property="Grid.Column" Value="{Binding Level}" /> 错误:来自HRESULT的异常:0x8000FFFF(E_UNEXPECTED)在edytor中,不在运行代码中。怎么了?在“旧” WPF中,一切正常,但是在适用于Windows 10的Universal App中,我出现了错误。谁能帮我 ?
<Setter Property="Grid.Column" Value="{Binding Level}" />
如MSDN 上Setter.Value属性页上的“ 迁移说明 ”部分所述,UWP / Windows运行时不支持样式设置器中的绑定。
Windows Presentation Foundation(WPF)和Microsoft Silverlight支持使用Binding表达式为样式中的Setter提供值的功能。Windows运行时不支持Setter.Value的绑定用法(该绑定不会评估,该Setter无效,您不会收到错误,但也不会获得所需的结果)。从WPF或Silverlight XAML转换XAML样式时,请使用设置值的字符串或对象替换任何绑定表达式用法,或将这些值重构为共享的{StaticResource}标记扩展值,而不是绑定获得的值。
解决方法可能是为绑定的源路径附加属性的帮助程序类。它在helper属性的PropertyChangedCallback中的代码后面创建绑定:
public class BindingHelper { public static readonly DependencyProperty GridColumnBindingPathProperty = DependencyProperty.RegisterAttached( "GridColumnBindingPath", typeof(string), typeof(BindingHelper), new PropertyMetadata(null, GridBindingPathPropertyChanged)); public static readonly DependencyProperty GridRowBindingPathProperty = DependencyProperty.RegisterAttached( "GridRowBindingPath", typeof(string), typeof(BindingHelper), new PropertyMetadata(null, GridBindingPathPropertyChanged)); public static string GetGridColumnBindingPath(DependencyObject obj) { return (string)obj.GetValue(GridColumnBindingPathProperty); } public static void SetGridColumnBindingPath(DependencyObject obj, string value) { obj.SetValue(GridColumnBindingPathProperty, value); } public static string GetGridRowBindingPath(DependencyObject obj) { return (string)obj.GetValue(GridRowBindingPathProperty); } public static void SetGridRowBindingPath(DependencyObject obj, string value) { obj.SetValue(GridRowBindingPathProperty, value); } private static void GridBindingPathPropertyChanged( DependencyObject obj, DependencyPropertyChangedEventArgs e) { var propertyPath = e.NewValue as string; if (propertyPath != null) { var gridProperty = e.Property == GridColumnBindingPathProperty ? Grid.ColumnProperty : Grid.RowProperty; BindingOperations.SetBinding( obj, gridProperty, new Binding { Path = new PropertyPath(propertyPath) }); } } }
您可以像这样在XAML中使用它们:
<ItemsControl.ItemContainerStyle> <Style TargetType="ContentPresenter"> <Setter Property="local:BindingHelper.GridColumnBindingPath" Value="Level"/> <Setter Property="local:BindingHelper.GridRowBindingPath" Value="Row"/> </Style> </ItemsControl.ItemContainerStyle>
有关绝对定位(即,绑定Canvas.Left和canvas.Top属性)的简单解决方法,请参见此答案。
Canvas.Left
canvas.Top