public static void ViewportThumbDragStarted(object sender, DragStartedEventArgs e)
{
var scrollThumb = VisualTreeExtraHelper.FindVisualParent <Thumb>(sender as DependencyObject);
if (scrollThumb != null)
{
OriginalWidth = scrollThumb.ActualWidth;
e.Handled = true;
}
}
public static void ViewportThumbDragDelta(object sender, DragDeltaEventArgs e)
{
var scrollThumb = VisualTreeExtraHelper.FindVisualParent <Thumb>(sender as DependencyObject);
if (scrollThumb != null)
{
var scrollThumbMargin = scrollThumb.Margin;
scrollThumbMargin.Left += e.HorizontalChange;
scrollThumb.Margin = scrollThumbMargin;
e.Handled = true;
}
}
public static void ViewportThumbDragCompleted(object sender, DragCompletedEventArgs e)
{
var scrollThumb = VisualTreeExtraHelper.FindVisualParent <Thumb>(sender as DependencyObject);
if (scrollThumb != null)
{
var newMarginLeft = scrollThumb.Margin.Left;
var change = (newMarginLeft - OriginalWidth) * -1;
var scale = OriginalWidth / scrollThumb.ActualWidth;
scrollThumb.Margin = new Thickness(-9, 1, -9, 1); // reset the margin back to what it was
ZoomViewportCommand.Execute(
new TimelineZoomViewportParameters()
{
ViewportAnchor = TimelineZoomAnchor.Right,
ViewportScale = scale
},
scrollThumb
);
e.Handled = true;
}
}