代码隐藏中的 WPF 用户控件动画不使用内容演示器
本文关键字：动画 隐藏 WPF 控件 用户 代码 | 更新日期: 2023-09-27 18:35:09
当代码像这样时，动画会按预期工作。
AnimatedUserControl2.xaml
<UserControl x:Class="WpfPoc20120908.AnimatedUserControl2"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300" IsVisibleChanged="AnimatedUserControl2_OnIsVisibleChanged">
<Grid Background="Coral">
<Canvas>
<TextBlock x:Name="MNB" Text="ABCD"/>
</Canvas>
</Grid>
</UserControl>
AnimatedUserControl2.xaml.cs（仅限部分代码）
private void AnimatedUserControl2_OnIsVisibleChanged(object sender, DependencyPropertyChangedEventArgs e)
{
if (Visibility == Visibility.Visible)
{
var storyboard = new Storyboard();
var visibilityAnimation = new ObjectAnimationUsingKeyFrames();
visibilityAnimation.KeyFrames.Add(new DiscreteObjectKeyFrame(Visibility.Visible,
KeyTime.FromTimeSpan(TimeSpan.FromSeconds(0))));
Storyboard.SetTargetProperty(visibilityAnimation, new PropertyPath(VisibilityProperty));
storyboard.Children.Add(visibilityAnimation);
var opacityAnimation = new DoubleAnimation(0, 1, new Duration(TimeSpan.FromSeconds(1)));
Storyboard.SetTargetProperty(opacityAnimation, new PropertyPath(OpacityProperty));
storyboard.Children.Add(opacityAnimation);
var canvasLeftAnimation = new DoubleAnimationUsingKeyFrames();
canvasLeftAnimation.KeyFrames.Add(new LinearDoubleKeyFrame(200,
KeyTime.FromTimeSpan(TimeSpan.FromSeconds(0))));
canvasLeftAnimation.KeyFrames.Add(new SplineDoubleKeyFrame(0, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(1)),
new KeySpline(new Point(0.25, 0.1),
new Point(0.25, 1))));
Storyboard.SetTargetProperty(canvasLeftAnimation, new PropertyPath(Canvas.LeftProperty));
storyboard.Children.Add(canvasLeftAnimation);
MNB.BeginStoryboard(storyboard, HandoffBehavior.SnapshotAndReplace, false);
}
}
但是，当我在 XAML 代码中使用内容演示器时，动画根本不起作用。
动画用户控件2.xaml（第 1 版）
<UserControl x:Class="WpfPoc20120908.AnimatedUserControl2"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300" IsVisibleChanged="AnimatedUserControl2_OnIsVisibleChanged">
<Grid Background="Coral">
<Canvas>
<ContentPresenter x:Name="MNB"/>
</Canvas>
</Grid>
</UserControl>
当我尝试用网格包装内容演示器时，动画仍然不起作用。
动画用户控件2.xaml（第2版）
<UserControl x:Class="WpfPoc20120908.AnimatedUserControl2"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300" IsVisibleChanged="AnimatedUserControl2_OnIsVisibleChanged">
<Grid Background="Coral">
<Canvas>
<Grid x:Name="MNB">
<ContentPresenter/>
</Grid>
</Canvas>
</Grid>
</UserControl>
问题来了。如何让动画与内容演示器配合使用？
更新 01
以下是 AnimatedUserControl2 的使用方式。
MainWindow.xaml（仅限部分代码）
<StackPanel Grid.Row="0" Orientation="Vertical">
<usercontrols:AnimatedUserControl2 x:Name="ABCD" Visibility="Hidden">
<TextBlock Text="ABC"/>
</usercontrols:AnimatedUserControl2>
<usercontrols:AnimatedUserControl2 x:Name="EFGH" Visibility="Hidden" Margin="10">
<TextBlock Text="ABC"/>
</usercontrols:AnimatedUserControl2>
</StackPanel>
<Button x:Name="ButtonBeginAnimation" Click="ButtonBeginAnimation_OnClick" Content="Begin Animation" Grid.Row="1"/>
MainWindow.xaml.cs（仅限部分代码）
private void ButtonBeginAnimation_OnClick(object sender, RoutedEventArgs e)
{
ABCD.Visibility = (ABCD.Visibility == Visibility.Visible) ? Visibility.Collapsed : Visibility.Visible;
EFGH.Visibility = (EFGH.Visibility == Visibility.Visible) ? Visibility.Collapsed : Visibility.Visible;
}
因此，问题在于您如何使用用户控件 - 您只需在 UserControl xaml 定义中指定后重写内容...无论如何。。尝试这种方法（动画在我的机器上工作，所以假设也可以在你的机器上工作;)）
<UserControl x:Class="WpfApplication11.UserControl1"
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"
d:DesignHeight="300"
d:DesignWidth="300"
mc:Ignorable="d">
<UserControl.Template>
<ControlTemplate TargetType="UserControl">
<Grid Background="Coral">
<Canvas>
<ContentPresenter x:Name="MNB" Content="{TemplateBinding Content}"/>
</Canvas>
</Grid>
</ControlTemplate>
</UserControl.Template>
而在动画本身中：
private void AnimatedUserControl2_OnIsVisibleChanged(object sender, EventArgs e)
{
var mnb = Template.FindName("MNB", this) as FrameworkElement;
if (mnb == null)
{
return;
}
if (Visibility == Visibility.Visible)
{
var storyboard = new Storyboard();
var visibilityAnimation = new ObjectAnimationUsingKeyFrames();
visibilityAnimation.KeyFrames.Add(new DiscreteObjectKeyFrame(Visibility.Visible,
KeyTime.FromTimeSpan(TimeSpan.FromSeconds(0))));
Storyboard.SetTargetProperty(visibilityAnimation, new PropertyPath(VisibilityProperty));
storyboard.Children.Add(visibilityAnimation);
var opacityAnimation = new DoubleAnimation(0, 1, new Duration(TimeSpan.FromSeconds(1)));
Storyboard.SetTargetProperty(opacityAnimation, new PropertyPath(OpacityProperty));
storyboard.Children.Add(opacityAnimation);
var canvasLeftAnimation = new DoubleAnimationUsingKeyFrames();
canvasLeftAnimation.KeyFrames.Add(new LinearDoubleKeyFrame(200,
KeyTime.FromTimeSpan(TimeSpan.FromSeconds(0))));
canvasLeftAnimation.KeyFrames.Add(new SplineDoubleKeyFrame(0, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(1)),
new KeySpline(new Point(0.25, 0.1),
new Point(0.25, 1))));
Storyboard.SetTargetProperty(canvasLeftAnimation, new PropertyPath(Canvas.LeftProperty));
storyboard.Children.Add(canvasLeftAnimation);
mnb.BeginStoryboard(storyboard, HandoffBehavior.SnapshotAndReplace, false);
}
}