WPF Marquee Text Animation

Question

I can scroll text with TranslateTransform but when the animation is close to finishing I\'d like it to begin again. Like a snake :)

This is what I\'ve g

Answer 1

Something like this should do the trick.

You can add a Canvas to the StackPanel with 2 TextBlocks one set to position 0 and one set to the ActualWidth of the StackPanel, then when the first block of text goes offscreen the other block will come into view.

The reason I used Canvas is because Canvas is the only element that actually supports ClipToBounds="false" this allows the 2nd TextBlock to be visible even if its placed outside the bounds of the Canvas itself

We also need a IValueConverter to get the correct negative value if you want to scroll from right to left.

I also added event trigger on SizeChanged so if the window is resized the animation values will update correctly.

Code:

namespace WpfApplication9
{
    /// 

    /// Interaction logic for MainWindow.xaml
    /// 
    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:

Result:

Edit: Left to Right