为PropertyPath内的动画指定GroupStyle.HeaderTemplate语法

Question

我试图在GroupStyle头中执行DataGrid上的旋转动画，但无法为Storyboard.TargetProperty属性提供PropertyPath语法。这里有一个包含的例子来突出我的问题

<Window x:Class="ImageRotateTest.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:sys="clr-namespace:System;assembly=mscorlib"
    Title="MainWindow" Height="350" Width="525">
<Window.DataContext>
    <x:Array Type="sys:String">
        <sys:String>One</sys:String>
        <sys:String>One</sys:String>
        <sys:String>Three</sys:String>
        <sys:String>Four</sys:String>
        <sys:String>Four</sys:String>
    </x:Array>
</Window.DataContext>

<Window.Resources>
    <CollectionViewSource Source="{Binding}" x:Key="ViewSource">
        <CollectionViewSource.GroupDescriptions>
            <PropertyGroupDescription></PropertyGroupDescription>
        </CollectionViewSource.GroupDescriptions>
    </CollectionViewSource>
</Window.Resources>

<DataGrid ItemsSource="{Binding Source={StaticResource ViewSource}}" AutoGenerateColumns="False">
    <DataGrid.GroupStyle>
        <GroupStyle>
            <GroupStyle.HeaderTemplate>
                <DataTemplate>
                    <TextBlock Text="{Binding Name}">
                        <TextBlock.RenderTransform>
                            <RotateTransform/>
                        </TextBlock.RenderTransform>
                        <TextBlock.Style>
                            <Style TargetType="TextBlock">
                                <Style.Triggers>
                                    <DataTrigger Binding="{Binding Name}" Value="Three">
                                        <DataTrigger.EnterActions>
                                            <BeginStoryboard x:Name="Test">
                                                <Storyboard>
                                                    <DoubleAnimation Storyboard.TargetProperty="RenderTransform.Angle" To="360" Duration="0:0:0.800" RepeatBehavior="Forever"/>
                                                </Storyboard>
                                            </BeginStoryboard>
                                        </DataTrigger.EnterActions>
                                        <DataTrigger.ExitActions>
                                            <StopStoryboard BeginStoryboardName="Test" />
                                        </DataTrigger.ExitActions>
                                    </DataTrigger>
                                </Style.Triggers>
                            </Style>
                        </TextBlock.Style>
                    </TextBlock>
                </DataTemplate>
            </GroupStyle.HeaderTemplate>
        </GroupStyle>
    </DataGrid.GroupStyle>
    <DataGrid.Columns>
        <DataGridTextColumn Binding="{Binding}" Header="Item" />
    </DataGrid.Columns>
</DataGrid>

​

这里的结果应该是，组标题应该只为“三”组而不是任何其他组旋转。但是，运行此操作将导致以下异常

A first chance exception of type 'System.Windows.Markup.XamlParseException' occurred in     PresentationFramework.dll

Additional information: Cannot resolve all property references in the property path 'RenderTransform.Angle'. Verify that applicable objects support the properties.

我为Storyboard.TargetProperty尝试了以下几种方法，但都没有成功

(TextBlock.RenderTransform).(RotateTransform.Angle)
(RenderTransform).(Angle)
RenderTransform.Angle

我的问题是:如何使用属性路径语法引用TextBlock.RenderTransform？

Answer 1

您的代码几乎可以正常工作。你只需要做一个改变：

Storyboard.TargetProperty="RenderTransform.(RotateTransform.Angle)"

我只用TextBlock测试了它，可以看到它在DataGrid中旋转，所以如果您看不到它在您的DataGrid中旋转，那么您的Name属性Binding是不正确的，或者它的值不是预期的"Three"。

<TextBlock Text="{Binding Name}">
    <TextBlock.RenderTransform>
        <RotateTransform/>
    </TextBlock.RenderTransform>
    <TextBlock.Style>
        <Style TargetType="TextBlock">
            <Style.Triggers>
                <DataTrigger Binding="{Binding Name}" Value="Three">
                    <DataTrigger.EnterActions>
                        <BeginStoryboard x:Name="Test">
                            <Storyboard>
                                <DoubleAnimation Storyboard.TargetProperty="
                                    RenderTransform.(RotateTransform.Angle)" To="360" 
                                    Duration="0:0:0.800" RepeatBehavior="Forever"/>
                            </Storyboard>
                        </BeginStoryboard>
                    </DataTrigger.EnterActions>
                    <DataTrigger.ExitActions>
                        <StopStoryboard BeginStoryboardName="Test" />
                    </DataTrigger.ExitActions>
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </TextBlock.Style>
</TextBlock>

Answer 2

对于对象的旋转，这是一个简单且最好的例子。

<Window x:Class="Animation.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Animated Rectangle" Height="350" Width="525">
<Grid>
    <StackPanel Margin="10">
        <Image Name="MyImage" Source="e:\a.jpg" Width="100" Margin="50" ></Image>
        <Rectangle
            Name="MyRectangle"
            Width="100" 
            Height="100"
            Fill="Blue">

            <Rectangle.Triggers>
                <!-- Animates the rectangle's opacity. -->
                <EventTrigger RoutedEvent="Rectangle.Loaded">
                    <BeginStoryboard>
                        <Storyboard>
                            <DoubleAnimation
                                Storyboard.TargetName="MyImage" 
                                Storyboard.TargetProperty="Opacity"
                                From="1.0" To="0.0" Duration="0:0:3" 
                                AutoReverse="True" RepeatBehavior="Forever" />
                        </Storyboard>
                    </BeginStoryboard>
                </EventTrigger>
            </Rectangle.Triggers>
        </Rectangle>
    </StackPanel>
</Grid>

​