6

在前面我想说：请不要建议替代解决方案，除非您可以在不修改 BaseXXXXXX 模式的类型的情况下完成它

也就是说，就我而言，这种行为超出了令人困惑的范围，似乎使用new关键字来隐藏 C# 中的属性意味着 WinRT XAML（Windows8、Metro、Windows Store App）绑定不再正常工作。我不知道为什么会这样。

这是一个例子：

C＃：

namespace WinRtSandbox
{
    public class BaseClass 
    {
        public string Property1 { get; set; }
        public int[] Property2 { get; set; }
        public object Property3 { get; set; }
    }


    public class ModifiedClass : BaseClass
    {
        public new string Property1 { get; set; }
        public new long[] Property2 { get; set; }
        public new string Property3 { get; set; }
    }

    public sealed partial class MainPage : Page
    {

        public BaseClass Normal { get; set; }
        public ModifiedClass Modified { get; set; }

        public MainPage()
        {
            this.Normal = new BaseClass
            {
                Property1 = "WTF",
                Property2 = new[] { 2, 3, 4 },
                Property3 = "Work?"
            };

            this.Modified = new ModifiedClass
            {
                Property1 = "WTF",
                Property2 = new[] { 2L, 3L, 4L },
                Property3 = "Work?"
            };

            this.InitializeComponent();
        }
    }
}

WinRT XAML：

<Page
    x:Class="WinRtSandbox.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:WinRtSandbox"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    DataContext="{Binding RelativeSource={RelativeSource Self}}"
    mc:Ignorable="d">

    <Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">
        <Border Background="#22000000" Padding="40" Width="400" Height="500">
            <Grid>

                <Grid.Resources>
                    <Style TargetType="Rectangle">
                        <Setter Property="Height" Value="1"/>
                        <Setter Property="HorizontalAlignment" Value="Stretch"/>
                        <Setter Property="Margin" Value="0,15,0,15"/>
                        <Setter Property="Fill" Value="{StaticResource ApplicationForegroundThemeBrush}"/>
                    </Style>
                </Grid.Resources>

                <Grid.ColumnDefinitions>
                    <ColumnDefinition/>
                    <ColumnDefinition/>
                </Grid.ColumnDefinitions>

                <StackPanel Grid.Column="0">

                    <ItemsControl>
                        <TextBlock Text="this.Normal"/>
                        <Rectangle/>
                        <TextBlock Text="this.Normal.Property1"/>
                        <Rectangle/>
                        <TextBlock Text="this.Normal.Property2"/>
                        <Rectangle/>
                        <TextBlock Text="this.Normal.Property3"/>
                    </ItemsControl>

                    <Rectangle Fill="Red"/>

                    <ItemsControl>
                        <TextBlock Text="this.Modified"/>
                        <Rectangle/>
                        <TextBlock Text="this.Modified.Property1"/>
                        <Rectangle/>
                        <TextBlock Text="this.Modified.Property2"/>
                        <Rectangle/>
                        <TextBlock Text="this.Modified.Property3"/>
                    </ItemsControl>

                </StackPanel>

                <StackPanel Grid.Column="1">

                    <ItemsControl DataContext="{Binding Normal}">
                        <TextBlock Text="{Binding}"/>
                        <Rectangle/>
                        <TextBlock Text="{Binding Property1}"/>
                        <Rectangle/>
                        <TextBlock Text="{Binding Property2}"/>
                        <Rectangle/>
                        <TextBlock Text="{Binding Property3}"/>
                    </ItemsControl>

                    <Rectangle Fill="Red"/>

                    <ItemsControl DataContext="{Binding Modified}">
                        <TextBlock Text="{Binding}"/>
                        <Rectangle/>
                        <TextBlock Text="{Binding Property1}"/>
                        <Rectangle/>
                        <TextBlock Text="{Binding Property2}"/>
                        <Rectangle/>
                        <TextBlock Text="{Binding Property3}"/>
                    </ItemsControl>

                </StackPanel>
            </Grid>
        </Border>

    </Grid>
</Page>

完全不正确的结果看起来像： 到底是怎么回事

基本上，这些空白行中的每一个都应该被填充，你们中的任何一个 XAML 能手都知道为什么这些绑定失败了，有什么可以解决我只能假设是一个令人发指的错误的方法吗？任何帮助或见解将不胜感激，在此先感谢您...-ck

更新：我忘记的输出转储

Error: BindingExpression path error: 'Property2' property not found on 'WinRtSandbox.ModifiedClass'. BindingExpression: Path='Property2' DataItem='WinRtSandbox.ModifiedClass'; target element is 'Windows.UI.Xaml.Controls.TextBlock' (Name='null'); target property is 'Text' (type 'String')
Error: BindingExpression path error: 'Property3' property not found on 'WinRtSandbox.ModifiedClass'. BindingExpression: Path='Property3' DataItem='WinRtSandbox.ModifiedClass'; target element is 'Windows.UI.Xaml.Controls.TextBlock' (Name='null'); target property is 'Text' (type 'String')

更新：

向 Microsoft 提交的错误：https ://connect.microsoft.com/VisualStudio/feedback/details/782993/binding-a-property-that-hides-another-in-winrt-xaml所以我们会看看情况如何

4

2 回答 2

1

我同意这确实是一个错误。

我知道你说你不想要替代品，但为了其他可能读到这个问题的人，我会忽略你。

您可以通过将每个属性都设置为 DependencyProperty 来解决此问题

public class BaseClass : DependencyObject
{
    public static readonly DependencyProperty Property1Property = DependencyProperty.Register(
        "Property1",
        typeof(string),
        typeof(BaseClass),
        new PropertyMetadata(null));

    public string Property1
    {
        get { return (string)GetValue(Property1Property); }
        set { SetValue(Property1Property, value); }
    }

    public static readonly DependencyProperty Property2Property = DependencyProperty.Register(
        "Property2",
        typeof(int[]),
        typeof(BaseClass),
        new PropertyMetadata(null));

    public int[] Property2
    {
        get { return (int[])GetValue(Property2Property); }
        set { SetValue(Property2Property, value); }
    }

    public static readonly DependencyProperty Property3Property = DependencyProperty.Register(
        "Property3",
        typeof(object),
        typeof(BaseClass),
        new PropertyMetadata(null));

    public object Property3
    {
        get { return GetValue(Property3Property); }
        set { SetValue(Property3Property, value); }
    }
}


public class ModifiedClass : BaseClass
{
    public static readonly new DependencyProperty Property1Property = DependencyProperty.Register(
        "Property1",
        typeof(string),
        typeof(ModifiedClass),
        new PropertyMetadata(null));

    public new string Property1
    {
        get { return (string)GetValue(Property1Property); }
        set { SetValue(Property1Property, value); }
    }

    public static readonly new DependencyProperty Property2Property = DependencyProperty.Register(
        "Property2",
        typeof(long[]),
        typeof(ModifiedClass),
        new PropertyMetadata(null));

    public new long[] Property2
    {
        get { return (long[])GetValue(Property2Property); }
        set { SetValue(Property2Property, value); }
    }

    public static readonly new DependencyProperty Property3Property = DependencyProperty.Register(
        "Property3",
        typeof(string),
        typeof(ModifiedClass),
        new PropertyMetadata(null));

    public new string Property3
    {
        get { return (string)GetValue(Property3Property); }
        set { SetValue(Property3Property, value); }
    }
}
于 2013-05-04T22:04:00.117 回答
0

事实证明这是一个“不受支持的错误”，无论这意味着什么......这是直接引用：

您好，很抱歉我们的回复晚了。到目前为止，我们不支持此错误。请访问http://support.microsoft.com或致电 1-800-MICROSOFT 寻求帮助。谢谢。

...希望这将在 .NET 4.5.1 中得到修复

查看错误报告： https ://connect.microsoft.com/VisualStudio/feedback/details/782993/binding-a-property-that-hides-another-in-winrt-xaml

于 2013-06-27T19:40:10.807 回答