public static UIElement FindRoot(DependencyObject visual)
{
var parentWindow = Window.GetWindow(visual);
var rootElement = parentWindow != null ? parentWindow.Content as UIElement : null;
if (rootElement == null)
{
if (Application.Current != null && Application.Current.MainWindow != null)
{
rootElement = Application.Current.MainWindow.Content as UIElement;
}
if (rootElement == null)
{
rootElement = visual.GetVisualAncestor<Page>() ?? visual.GetVisualAncestor<UserControl>() as UIElement;
}
}
// i don't want the fu... windows forms reference
// if (rootElement == null) {
// var elementHost = m_DragInfo.VisualSource.GetVisualAncestor<ElementHost>();
// rootElement = elementHost != null ? elementHost.Child : null;
// }
return rootElement;
}
static void Scroll(DependencyObject o, DragEventArgs e)
{
ScrollViewer scrollViewer = o.GetVisualAncestor<ScrollViewer>();//o.GetVisualDescendent<ScrollViewer>();
if (scrollViewer != null)
{
Point position = e.GetPosition(scrollViewer);
double scrollMargin = Math.Min(scrollViewer.FontSize * 4, 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();
}
}
}
