绑定到达的依赖属性的触发器/设置器

Question

我想设置一个我在Class1 中声明的依赖属性，它继承自DependencyObject：

public static readonly DependencyProperty MyMouseOverProperty = DependencyProperty.Register("MyMouseOver", typeof(bool), typeof(Class1), 
                                                                                             new PropertyMetadata(false,new PropertyChangedCallback(On_MyMouseOver)));

    private static void On_MyMouseOver(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
       // some code here

    }

    public bool MyMouseOver
    {
        get { return (bool)GetValue(MyMouseOverProperty); }
        set { SetValue(MyMouseOverProperty, value); }
    }

我将在 XAML 中使用“MyMouseOver”，以便在“On_MyMouseOver”中使用其状态来影响另一个对象。

 <DataTemplate DataType="{x:Type local:Class1}">
                <Canvas x:Name="Canvas_Classe1"
                        Background="Transparent">

                     <Canvas.Triggers>
                        <Trigger Property="IsMouseOver" Value="True">
                            <Setter Property="{Binding Path=MyMouseOver}" Value="True"/>
                        </Trigger>
                    </Canvas.Triggers>

                </Canvas>

但是……这行不通。 如何使用Setter 访问DependencyProperty 声明的不是在控件中而是在类中？

Answer 1

您可以通过attached property 完成此操作

public class Class1 
{
    public static readonly DependencyProperty MyMouseOverProperty = DependencyProperty.RegisterAttached(
        "MyMouseOver", typeof(bool), typeof(Class1), new FrameworkPropertyMetadata(false, PropertyChangedCallback)
    );

    public static void SetMyMouseOver(UIElement element, Boolean value)
    {
        element.SetValue(MyMouseOverProperty, value);
    }

    public static bool GetMyMouseOver(UIElement element)
    {
        return (bool)element.GetValue(MyMouseOverProperty);
    }

    private static void PropertyChangedCallback(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        // some code here
    }
}

在 DataTemplate IsMouseOver 上设置附加属性

<DataTemplate DataType="{x:Type local:Class1}">
        <Canvas x:Name="Canvas_Classe1"
                Background="Black">
        </Canvas>
        <DataTemplate.Triggers>
            <Trigger Property="IsMouseOver" Value="True">
                <Setter Property="local:Class1.MyMouseOver" Value="True"/>
            </Trigger>
        </DataTemplate.Triggers>
</DataTemplate>