wpf - WPF字幕文本动画

Question

我可以使用TranslateTransform滚动文本，但是当动画快要完成时，我希望它重新开始。像蛇一样:)

这就是我得到的：

<StackPanel Orientation="Horizontal" Margin="0,0,0,0">
    <StackPanel.RenderTransform>
        <TranslateTransform x:Name="transferCurreny" X="-40"/>
    </StackPanel.RenderTransform>
    <StackPanel.Triggers>
        <EventTrigger RoutedEvent="StackPanel.Loaded">
            <BeginStoryboard>
                <Storyboard>
                    <DoubleAnimation From="0" To="-900" Duration="00:00:10"
                      Storyboard.TargetProperty="X"
                      Storyboard.TargetName="transferCurreny"
                      RepeatBehavior="Forever"/>
                </Storyboard>
            </BeginStoryboard>
        </EventTrigger>
    </StackPanel.Triggers>
    <TextBlock FontSize="25"  x:Name="txtKron" Margin="10,0,7,0"/>
</StackPanel>

这就是我想要的：

Answer 1

这样的事情应该可以解决问题。

您可以在Canvas中添加一个StackPanel，将2个TextBlocks设置为位置0，将一个ActualWidth设置为StackPanel的Canvas，然后当第一个文本块离开屏幕时，另一个块将出现进入视野。

我使用Canvas的原因是因为ClipToBounds="false"是唯一实际支持TextBlock的元素，这即使第2个Canvas放置在IValueConverter本身的范围之外也可以显示

如果您想从右向左滚动，我们还需要一个SizeChanged以获得正确的负值。

我还在 上添加了事件触发器，因此，如果调整窗口大小，动画值将正确更新。

码：

namespace WpfApplication9
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {

        public MainWindow()
        {
            InitializeComponent();
        }
    }

    public class NegatingConverter : IValueConverter
    {

        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if (value is double)
            {
                return -((double)value);
            }
            return value;
        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if (value is double)
            {
                return +(double)value;
            }
            return value;
        }
    }
}

Xaml：

<Window x:Class="WpfApplication9.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:WpfApplication9"
        Title="MainWindow" Height="83" Width="222" Name="UI" Tag="Tol Level">
    <StackPanel Orientation="Horizontal" x:Name="stack">
        <StackPanel.Resources>
            <local:NegatingConverter x:Key="NegatingConverter" />
            <Storyboard x:Key="slide">
                <DoubleAnimation From="0" To="{Binding Width, ElementName=canvas, Converter={StaticResource NegatingConverter}}" Duration="00:00:10"
                      Storyboard.TargetProperty="X"
                      Storyboard.TargetName="transferCurreny"
                      RepeatBehavior="Forever"/>
            </Storyboard>
        </StackPanel.Resources>
        <StackPanel.RenderTransform>
            <TranslateTransform x:Name="transferCurreny" X="0"/>
        </StackPanel.RenderTransform>
        <StackPanel.Triggers>
            <EventTrigger RoutedEvent="StackPanel.Loaded">
                <BeginStoryboard Storyboard="{StaticResource slide}" />
            </EventTrigger>
            <EventTrigger RoutedEvent="StackPanel.SizeChanged">
                <BeginStoryboard Storyboard="{StaticResource slide}" />
            </EventTrigger>
        </StackPanel.Triggers>
        <Canvas x:Name="canvas" Width="{Binding ActualWidth, ElementName=stack}">
            <TextBlock Text="StackOverflow" FontSize="25"  x:Name="txtKron" Canvas.Left="0"/>
            <TextBlock Text="{Binding Text, ElementName=txtKron}" FontSize="25" Canvas.Left="{Binding Width, ElementName=canvas}"/>
        </Canvas>
    </StackPanel>
</Window>

结果：



编辑：从左到右

 <StackPanel Orientation="Horizontal" x:Name="stack">
        <StackPanel.Resources>
            <local:NegatingConverter x:Key="NegatingConverter" />
            <Storyboard x:Key="slide">
                <DoubleAnimation From="0" To="{Binding Width, ElementName=canvas}" Duration="00:00:10"
                      Storyboard.TargetProperty="X"
                      Storyboard.TargetName="transferCurreny"
                      RepeatBehavior="Forever"/>
            </Storyboard>
        </StackPanel.Resources>
        <StackPanel.RenderTransform>
            <TranslateTransform x:Name="transferCurreny" X="0"/>
        </StackPanel.RenderTransform>
        <StackPanel.Triggers>
            <EventTrigger RoutedEvent="StackPanel.Loaded">
                <BeginStoryboard Storyboard="{StaticResource slide}" />
            </EventTrigger>
            <EventTrigger RoutedEvent="StackPanel.SizeChanged">
                <BeginStoryboard Storyboard="{StaticResource slide}" />
            </EventTrigger>
        </StackPanel.Triggers>
        <Canvas x:Name="canvas" Width="{Binding ActualWidth, ElementName=stack}">
            <TextBlock Text="StackOverflow" FontSize="25"  x:Name="txtKron" Canvas.Left="0"/>
            <TextBlock Text="{Binding Text, ElementName=txtKron}" FontSize="25" Canvas.Left="{Binding Width, ElementName=canvas, Converter={StaticResource NegatingConverter}}"/>
        </Canvas>
    </StackPanel>