static void Scroll(DependencyObject o, DragEventArgs e)
{
ScrollViewer scrollViewer = o.GetVisualDescendent<ScrollViewer>();
if (scrollViewer != null)
{
Point position = e.GetPosition(scrollViewer);
double scrollMargin = Math.Min(scrollViewer.FontSize * 2, scrollViewer.ActualHeight / 2);
if (position.X >= scrollViewer.ActualWidth - scrollMargin &&
scrollViewer.HorizontalOffset < scrollViewer.ExtentWidth - scrollViewer.ViewportWidth)
{
scrollViewer.LineRight();
}
else if (position.X < scrollMargin && scrollViewer.HorizontalOffset > 0)
{
scrollViewer.LineLeft();
}
else if (position.Y >= scrollViewer.ActualHeight - scrollMargin &&
scrollViewer.VerticalOffset < scrollViewer.ExtentHeight - scrollViewer.ViewportHeight)
{
scrollViewer.LineDown();
}
else if (position.Y < scrollMargin && scrollViewer.VerticalOffset > 0)
{
scrollViewer.LineUp();
}
}
}
private static void Scroll(DependencyObject visualTarget, DragEventArgs e)
{
ScrollViewer scrollViewer = null;
if (visualTarget is TabControl)
{
var tabPanel = visualTarget.GetVisualDescendent<TabPanel>();
if (tabPanel != null)
{
scrollViewer = tabPanel.GetVisualAncestor<ScrollViewer>();
if (scrollViewer == null)
{
return;
}
}
}
scrollViewer = scrollViewer ?? visualTarget.GetVisualDescendent<ScrollViewer>();
if (scrollViewer != null) {
var position = e.GetPosition(scrollViewer);
var scrollMargin = Math.Min(scrollViewer.FontSize * 2, scrollViewer.ActualHeight / 2);
if (position.X >= scrollViewer.ActualWidth - scrollMargin &&
scrollViewer.HorizontalOffset < scrollViewer.ExtentWidth - scrollViewer.ViewportWidth) {
scrollViewer.LineRight();
} else if (position.X < scrollMargin && scrollViewer.HorizontalOffset > 0) {
scrollViewer.LineLeft();
} else if (position.Y >= scrollViewer.ActualHeight - scrollMargin &&
scrollViewer.VerticalOffset < scrollViewer.ExtentHeight - scrollViewer.ViewportHeight) {
scrollViewer.LineDown();
} else if (position.Y < scrollMargin && scrollViewer.VerticalOffset > 0) {
scrollViewer.LineUp();
}
}
}
