Question

我开始使用WPF（曾经习惯使用winforms）。

我正在尝试旋转图像，并希望使用故事板，因为在下一阶段我需要添加多个运行时间的动画。

我的代码位于按钮的单击事件中，如下所示：

//start the animation
            DoubleAnimation animationRotation = new DoubleAnimation();

            animationRotation.From = -17;
            animationRotation.To = 17;
            animationRotation.Duration = new Duration(TimeSpan.FromMilliseconds(NumericDisplay.Milliseconds));
            animationRotation.RepeatBehavior = RepeatBehavior.Forever;
            animationRotation.AccelerationRatio = 0.3;
            animationRotation.DecelerationRatio = 0.3;
            animationRotation.AutoReverse = true;

            Storyboard storyboard = new Storyboard();

            Storyboard.SetTarget(animationRotation, Arm);
            Storyboard.SetTargetProperty(animationRotation,
              new PropertyPath("(UIElement.RenderTransform).(TransformGroup.Children)[0].(RotateTransform.Angle)")); 

            storyboard.Children.Add(animationRotation);

            // Add the storyboard to the tracking collection.      
            //this.Stostoryboards.Add(bomb, storyboard);

            // Configure and start the storyboard.
            this.BeginStoryboard(storyboard);

代码编译时没有警告，但click事件不会启动动画，

修改其中一个建议的答案让我检查XAML包含了一个rotatetransform的定义...下面的XAML是我正在使用的

<UserControl
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:my="clr-namespace:MetronomeLibrary" xmlns:Microsoft_Windows_Themes="clr-namespace:Microsoft.Windows.Themes;assembly=PresentationFramework.Aero"
mc:Ignorable="d"
x:Class="MetronomeLibrary.MetronomeLarge"
x:Name="UserControl" Height="386" Width="1024" SizeChanged="UserControl_SizeChanged">
<UserControl.Resources>
    <ResourceDictionary>
        <ResourceDictionary.MergedDictionaries>
            <ResourceDictionary Source="ResourceDictionary.xaml"/>
        </ResourceDictionary.MergedDictionaries>
        <ImageBrush x:Key="ImageBrush_Decrement" ImageSource="Images/pad-metronome-decrement-button.png" Stretch="Fill"/>
        <ImageBrush x:Key="ImageBrush_Increment" ImageSource="Images/pad-metronome-increment-button.png" Stretch="Fill"/>

    </ResourceDictionary>
</UserControl.Resources>
<UserControl.Triggers>
    <EventTrigger RoutedEvent="FrameworkElement.Loaded">

    </EventTrigger>
</UserControl.Triggers>

<Grid x:Name="LayoutRoot" Height="412">
    <Image x:Name="MetronomeWindowBackground" Height="140" Margin="237,1.5,231,0" Source="Images\pad-metronome-top-under-bg.png" Stretch="Fill" VerticalAlignment="Top"/>
    <Image x:Name="Arm" Margin="506,17,493,0" Source="Images\pad-metronome-arm.png" Stretch="Fill" Height="326" VerticalAlignment="Top" RenderTransformOrigin="0.5,0.5">
        <Image.RenderTransform>
            <TransformGroup>
                <RotateTransform/>

            </TransformGroup>
        </Image.RenderTransform>
    </Image>
    <Image x:Name="MetronomeFlash" Height="209" Margin="104,0,96,0" Source="Images\pad-metronome-flash-top-landscape.png" Stretch="Fill" VerticalAlignment="Top" d:IsHidden="True" />
    <Image x:Name="MetronomeBackground" Height="209" Source="Images\pad-metronome-top-bg-landscape.png" Stretch="Fill" VerticalAlignment="Top" Margin="3,0,-3,0"/>
    <Image x:Name="MetronomeStartButton" Margin="379.5,100.5,373.5,0" Source="Images\pad-metronome-start-button-base.png" Stretch="Fill" Height="110" VerticalAlignment="Top"/>
    <Image x:Name="MetronomeTapPadLeft" HorizontalAlignment="Left" Height="209" Margin="5,1.5,0,0" Source="Images\pad-metronome-tap-pad-left.png" Stretch="Fill" VerticalAlignment="Top" Width="136"/>
    <Image x:Name="MetronomeTapPadRight" HorizontalAlignment="Right" Source="Images\pad-metronome-tap-pad-right.png" Stretch="Fill" Width="136" Height="209" VerticalAlignment="Top"/>
    <Image x:Name="MetronomeWindowHighlight" Height="105" Margin="238.5,18,231.5,0" Source="Images\pad-metronome-window-overlay.png" Stretch="Fill" VerticalAlignment="Top"/>
    <Image x:Name="MetronomeBottomBackground" Margin="3,208,-3,362" Source="Images\pad-metronome-section-bottom-bg.png" Stretch="Fill"/>
    <my:MetronomeLargeNumericDisplay HorizontalAlignment="Left" Margin="459,120,0,0" x:Name="NumericDisplay" VerticalAlignment="Top" Value="999" Width="122.25" />
    <Image Height="78" Margin="448,110.5,436,0" Source="Images\pad-metronome-start-button-overlay.png" Stretch="Fill" VerticalAlignment="Top"
           x:Name="DisplayOverlay" MouseDown="DisplayOverlay_MouseDown" />
    <RepeatButton x:Name="ButtonDecrement" Content="" BorderThickness="7" HorizontalAlignment="Left" Margin="252,110.5,0,0" VerticalAlignment="Top" Width="149" Height="100" Background="{DynamicResource ImageBrush_Decrement}" Style="{DynamicResource RepeatButtonStyle_noflash}" BorderBrush="{DynamicResource ImageBrush_Decrement}" d:LayoutOverrides="HorizontalAlignment" Click="ButtonDecrement_Click"></RepeatButton>
    <RepeatButton Content="" BorderThickness="7" HorizontalAlignment="Left" Margin="631,110.5,0,0" VerticalAlignment="Top" Width="149" Height="100" Background="{DynamicResource ImageBrush_Increment}" Style="{DynamicResource RepeatButtonStyle_noflash}" BorderBrush="{DynamicResource ImageBrush_Decrement}" Name="ButtonIncrement" Click="ButtonIncrement_Click" />
</Grid>

我做错了什么？

Answer 1

您发布的代码似乎没问题，但是，路径指的是现有的元素，因此请确保您已在xaml中包含适当的节点，其中Arm控制是定义。

假设Arm是Rectangle控件。你的xaml应该或多或少看起来像这样：

...
<Rectangle x:Name="Arm" Fill="Aqua" Width="100" Height="100" Canvas.Left="100" Canvas.Top="100">
    <Rectangle.RenderTransform>
        <TransformGroup>
            <RotateTransform />
        </TransformGroup>
    </Rectangle.RenderTransform>
</Rectangle>
...

Arm可以是另一种类型的控件，但重要的是定义了RenderTransform，TransformGroup和RotateTransform个节点，因此动画中有一些现有元素需要更改在代码中的PropertyPath中指定。

Answer 2

经过多次搞乱新项目和简化的代码之后，我在另一个帖子中略有不同地问了这个问题，有人发布了工作代码。

关于调查我的动画不起作用的原因是我提供了动画的持续时间而不是故事板本身！ DOH。

这里的完整答案（这是我收到的关于这个主题的最完整的答案之一）

How do I create a rotate animation on an image object using c# code only (inside a WPF window)

卢卡斯，感谢你对这个问题的耐心和帮助。

丹

如何使用c＃代码创建故事板并在wpf中旋转图像

2 个答案: