WPF中的可视状态管理器不适用于我

在wpf项目中，我有以下XAML代码

<Window
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"
mc:Ignorable="d" 
xmlns:ic="clr-namespace:Microsoft.Expression.Interactivity.Core;assembly=Microsoft.Expression.Interactions"
x:Class="WpfApplication1.MainWindow"
xmlns:vsm="clr-namespace:System.Windows;assembly=WPFToolkit"
x:Name="Window"
Title="MainWindow"
Width="640" Height="480">
<vsm:VisualStateManager.VisualStateGroups>
    <vsm:VisualStateGroup x:Name="VisualStateGroup">
        <vsm:VisualState x:Name="Loading">
            <Storyboard>
                <ObjectAnimationUsingKeyFrames BeginTime="00:00:00" Duration="00:00:00.0010000" Storyboard.TargetName="control" Storyboard.TargetProperty="(UIElement.Visibility)">
                    <DiscreteObjectKeyFrame KeyTime="00:00:00" Value="{x:Static Visibility.Visible}"/>
                </ObjectAnimationUsingKeyFrames>
                <ObjectAnimationUsingKeyFrames BeginTime="00:00:00" Duration="00:00:00.0010000" Storyboard.TargetName="button" Storyboard.TargetProperty="(UIElement.Visibility)">
                    <DiscreteObjectKeyFrame KeyTime="00:00:00" Value="{x:Static Visibility.Collapsed}"/>
                </ObjectAnimationUsingKeyFrames>
                <ObjectAnimationUsingKeyFrames BeginTime="00:00:00" Duration="00:00:00.0010000" Storyboard.TargetName="button1" Storyboard.TargetProperty="(UIElement.Visibility)">
                    <DiscreteObjectKeyFrame KeyTime="00:00:00" Value="{x:Static Visibility.Visible}"/>
                </ObjectAnimationUsingKeyFrames>
            </Storyboard>
        </vsm:VisualState>
        <VisualState x:Name="Normal">
            <Storyboard>
                <ObjectAnimationUsingKeyFrames BeginTime="00:00:00" Duration="00:00:00.0010000" Storyboard.TargetName="control" Storyboard.TargetProperty="(UIElement.Visibility)">
                    <DiscreteObjectKeyFrame KeyTime="00:00:00" Value="{x:Static Visibility.Collapsed}"/>
                </ObjectAnimationUsingKeyFrames>
            </Storyboard>
        </VisualState>
    </vsm:VisualStateGroup>
</vsm:VisualStateManager.VisualStateGroups>
<Grid x:Name="LayoutRoot">
    <Grid.Resources>
        <ControlTemplate x:Key="loadingAnimation">
            <Image x:Name="content" Opacity="1">
                <Image.Source>
                    <DrawingImage>
                        <DrawingImage.Drawing>
                            <DrawingGroup>
                                <GeometryDrawing Brush="Transparent">
                                    <GeometryDrawing.Geometry>
                                        <RectangleGeometry Rect="0,0,1,1"/>
                                    </GeometryDrawing.Geometry>
                                </GeometryDrawing>
                                <DrawingGroup>
                                    <DrawingGroup.Transform>
                                        <RotateTransform x:Name="angle" Angle="0" CenterX="0.5" CenterY="0.5"/>
                                    </DrawingGroup.Transform>
                                    <GeometryDrawing Geometry="M0.9,0.5 A0.4,0.4,90,1,1,0.5,0.1">
                                        <GeometryDrawing.Pen>
                                            <Pen Brush="Green" Thickness="0.1"/>
                                        </GeometryDrawing.Pen>
                                    </GeometryDrawing>
                                    <GeometryDrawing Brush="Green" Geometry="M0.5,0 L0.7,0.1 L0.5,0.2"/>
                                </DrawingGroup>
                            </DrawingGroup>
                        </DrawingImage.Drawing>
                    </DrawingImage>
                </Image.Source>
            </Image>
            <ControlTemplate.Triggers>
                <Trigger Property="Visibility" Value="Visible">
                    <Trigger.EnterActions>
                        <BeginStoryboard x:Name="animation">
                            <Storyboard>
                                <DoubleAnimation From="0" To="359" Duration="0:0:1.5" RepeatBehavior="Forever"
                                    Storyboard.TargetName="angle" Storyboard.TargetProperty="Angle"/>
                            </Storyboard>
                        </BeginStoryboard>
                    </Trigger.EnterActions>
                    <Trigger.ExitActions>
                        <StopStoryboard BeginStoryboardName="animation"/>
                    </Trigger.ExitActions>
                </Trigger>
            </ControlTemplate.Triggers>
        </ControlTemplate>
    </Grid.Resources>
    <Grid.ColumnDefinitions>
        <ColumnDefinition MinWidth="76.128" Width="Auto"/>
        <ColumnDefinition MinWidth="547.872" Width="Auto"/>
    </Grid.ColumnDefinitions>
    <Grid.RowDefinitions>
        <RowDefinition Height="0.05*"/>
        <RowDefinition Height="0.95*"/>
    </Grid.RowDefinitions>
    <Button x:Name="button" Margin="0,0,1,0.04" Width="100" Content="Load" d:LayoutOverrides="Height" Click="Button1_Click"/>
    <Button x:Name="button1" HorizontalAlignment="Left" Margin="0,0,0,0.04" Width="100" Content="Stop" Grid.Column="1" d:LayoutOverrides="Height" Click="Button2_Click" Visibility="Collapsed"/>
    <Control x:Name="control" Margin="10" Height="100" Grid.Row="1" Grid.ColumnSpan="2" Width="100" Template="{DynamicResource loadingAnimation}" Visibility="Collapsed"/>
</Grid>
</Window>

但是，当我单击第一个按钮（按钮1）时，状态更改不会被触发。 我做错了什么

---

根据，当您在控件模板之外使用可视状态管理器时，应使用

GoToElementState

方法，而不是

GoToState

方法。不过，我还没有测试它。

我尝试了您的代码，但在设计器（VS2008 SP1）中出错：

值不能为空。
参数名称：值

每当我编辑情节提要代码时。重新加载xaml暂时“修复”了问题。代码仍在生成和运行，但我怀疑此错误的原因可能与您的问题有关

DiscreteObjectKeyFrame

的定义对我来说有点不合适。我在过去看到的唯一方法是，在何处这样做：

<vsm:VisualState x:Name="Focused">
  <Storyboard>
    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="FocusVisualElement"
                          Storyboard.TargetProperty="Visibility" Duration="0">
      <DiscreteObjectKeyFrame KeyTime="0">
        <DiscreteObjectKeyFrame.Value>
          <Visibility>Visible</Visibility>
        </DiscreteObjectKeyFrame.Value>
      </DiscreteObjectKeyFrame>
    </ObjectAnimationUsingKeyFrames>
  </Storyboard>
</vsm:VisualState>

看得见的

然而，我尝试了你的代码，但仍然无法让它工作，所以我即使是这样

---

一个问题它不是全部问题。

事实上，它是在.NET3.5上设计的。有一个解决方法。

创建一个附加属性以更改视觉状态。这对你有用

  public class StateManager : DependencyObject
        {
            public static string GetVisualStateProperty(DependencyObject obj)
            {
                return (string)obj.GetValue(VisualStatePropertyProperty);
            }

            public static void SetVisualStateProperty(DependencyObject obj, string value)
            {
                obj.SetValue(VisualStatePropertyProperty, value);
            }
                public static readonly DependencyProperty VisualStatePropertyProperty =
              DependencyProperty.RegisterAttached(
              "VisualStateProperty",
              typeof(string),
              typeof(StateManager),
              new PropertyMetadata((s, e) =>
              {
                  var propertyName = (string)e.NewValue;
                  var ctrl = s as Grid;  
                  if (ctrl == null)
                      throw new InvalidOperationException("This attached property only supports types derived from FrameworkElement.");
                  var transitionWorked = System.Windows.VisualStateManager.GoToElementState(ctrl, (string)e.NewValue, true);
                               }));
        }

---

我想您指的是v4.0 VisualStateManager。v3.5工具包上的版本不包含该方法。对于

GoToElementState

方法，您需要使用

ExtendedVisualStateManager

。您是指

GoToElementState

方法吗？该代码是由Blend生成的，因此我不知道它有什么错误。我仍然感到惊讶的是，还没有人能快速解决一个看似很小的问题。问题是你发布的代码没有生成，因为你的第一个按钮在codebehind中没有处理程序。确保您的代码生成时没有错误并运行，然后再次发布。@Román-OK-如果Blend生成了它，它必须是合法的。我关于错误的观点仍然存在。修复代码。您的XAML与您的codebehind不匹配。Button_Click handler在哪里？@majocha:很抱歉，我在做更改之前复制了XAML。这是不可能的，这不是这里的交易

  public class StateManager : DependencyObject
        {
            public static string GetVisualStateProperty(DependencyObject obj)
            {
                return (string)obj.GetValue(VisualStatePropertyProperty);
            }

            public static void SetVisualStateProperty(DependencyObject obj, string value)
            {
                obj.SetValue(VisualStatePropertyProperty, value);
            }
                public static readonly DependencyProperty VisualStatePropertyProperty =
              DependencyProperty.RegisterAttached(
              "VisualStateProperty",
              typeof(string),
              typeof(StateManager),
              new PropertyMetadata((s, e) =>
              {
                  var propertyName = (string)e.NewValue;
                  var ctrl = s as Grid;  
                  if (ctrl == null)
                      throw new InvalidOperationException("This attached property only supports types derived from FrameworkElement.");
                  var transitionWorked = System.Windows.VisualStateManager.GoToElementState(ctrl, (string)e.NewValue, true);
                               }));
        }