依赖项属性值优先级和动画

我正在使用 DoubleAnimation . 在触发动画之前,任何本地或 Setter ClearValue 和 InvalidateProperty 打电话也一样 SetValue

有办法纠正这种行为吗?我想使用动画更改属性值,但仍然可以手动或通过 去做任何事。我知道一两件事 Dependency Property Value Precedence 但我现在的行为有点奇怪。我不想用“手动动画”。

编辑:添加了示例XAML+代码。

<Window x:Class="WpfApplication7.Window1"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Window1" Height="300" Width="300"
        x:Name="_this"
        Background="Red">
    <DockPanel>
        <StackPanel DockPanel.Dock="Bottom" Orientation="Horizontal" HorizontalAlignment="Center" >
            <Button Click="ToggleOnClick">Toggle!</Button>
            <Button Click="SetHalfOnClick">Set to 0.5!</Button>
        </StackPanel>
        <TextBox DockPanel.Dock="Bottom" IsReadOnly="True" Text="{Binding ElementName=_viewbox,Path=Opacity}" />
        <Viewbox x:Name="_viewbox">
            <Viewbox.Style>
                <Style TargetType="{x:Type FrameworkElement}">
                    <Style.Triggers>
                        <DataTrigger Binding="{Binding Path=IsToggled,ElementName=_this,Mode=OneWay}" Value="True">
                            <DataTrigger.EnterActions>
                                <BeginStoryboard>
                                    <Storyboard>
                                        <DoubleAnimation To="0.2"
                                                 Duration="0:0:0.5"
                                                 Storyboard.TargetProperty="(UIElement.Opacity)" />
                                    </Storyboard>
                                </BeginStoryboard>
                            </DataTrigger.EnterActions>
                            <DataTrigger.ExitActions>
                                <BeginStoryboard>
                                    <Storyboard>
                                        <DoubleAnimation To="1"
                                                 Duration="0:0:0.5"
                                                 Storyboard.TargetProperty="(UIElement.Opacity)" />
                                    </Storyboard>
                                </BeginStoryboard>
                            </DataTrigger.ExitActions>
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
            </Viewbox.Style>

            <TextBlock Text="Sample!" />
        </Viewbox>
    </DockPanel>
</Window>

代码如下:

using System.Windows;

namespace WpfApplication7
{
    /// <summary>
    /// Interaction logic for Window1.xaml
    /// </summary>
    public partial class Window1
    {
        public bool IsToggled
        {
            get { return (bool)GetValue(IsToggledProperty); }
            set { SetValue(IsToggledProperty, value); }
        }

        public static readonly DependencyProperty IsToggledProperty = DependencyProperty.Register("IsToggled", typeof(bool), typeof(Window1), new UIPropertyMetadata(false));

        public Window1()
        {
            InitializeComponent();
        }

        private void ToggleOnClick(object sender, RoutedEventArgs e)
        {
            IsToggled = !IsToggled;
        }

        private void SetHalfOnClick(object sender, RoutedEventArgs e)
        {
            _viewbox.Opacity = 0.5;
        }
    }
}