WPF Marquee文本动画

Question

我可以滚动文本,TranslateTransform但是当动画接近结束时,我希望它再次开始.像蛇一样:)

这就是我所拥有的:

<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.

你可以添加a Canvas到StackPanel2的TextBlocks一个集合到位置0和一个集合ActualWidth的StackPanel,然后当第一个文本块离开屏幕时,另一个块将进入视图.

我使用的原因Canvas是因为Canvas实际支持ClipToBounds="false"它的唯一元素允许第二个TextBlock可见,即使它被放置在Canvas自身的边界之外

IValueConverter如果要从右向左滚动,我们还需要a 来获取正确的负值.

我还添加了事件触发器,SizeChanged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>