void ThumbDragStarted(object sender, DragStartedEventArgs e)
{
Thumb thumb = (Thumb)sender;
ScrollBar scrollBar = thumb.GetParent <ScrollBar>();
bool isVertical = scrollBar.Orientation == Orientation.Vertical;
// Update the content in the ToolTip
ScrollingPreviewData data = new ScrollingPreviewData();
data.UpdateScrollingValues(scrollBar);
data.UpdateItem(AssociatedObject as ItemsControl, isVertical);
_previewToolTip = new ToolTip
{
PlacementTarget = (UIElement)sender,
Placement = isVertical ? PlacementMode.Left : PlacementMode.Top,
VerticalOffset = 0.0,
HorizontalOffset = 0.0,
ContentTemplate = (isVertical)
? VerticalScrollingPreviewTemplate
: HorizontalScrollingPreviewTemplate,
Content = data,
IsOpen = true
};
}
void ScrollBar_Scroll(object sender, ScrollEventArgs e)
{
ScrollBar scrollBar = (ScrollBar)sender;
if (_previewToolTip != null)
{
// The ScrollBar's value isn't updated quite yet, so wait until Input priority
AssociatedObject.Dispatcher.BeginInvoke((Action)(() =>
{
ScrollingPreviewData data = (ScrollingPreviewData)_previewToolTip?.Content;
data?.UpdateScrollingValues(scrollBar);
data?.UpdateItem(AssociatedObject as ItemsControl, scrollBar.Orientation == Orientation.Vertical);
}
), DispatcherPriority.Input);
}
}
void ThumbDragStarted(object sender, DragStartedEventArgs e)
{
_previewToolTip = new ToolTip();
ScrollingPreviewData data = new ScrollingPreviewData();
_previewToolTip.Content = data;
// Update the content in the ToolTip
data.UpdateScrollingValues(AssociatedObject);
// Set the Placement and the PlacementTarget
_previewToolTip.PlacementTarget = (UIElement)sender;
_previewToolTip.Placement = AssociatedObject.Orientation == Orientation.Vertical ? PlacementMode.Left : PlacementMode.Top;
_previewToolTip.VerticalOffset = 0.0;
_previewToolTip.HorizontalOffset = 0.0;
_previewToolTip.ContentTemplate = ScrollingPreviewTemplate;
_previewToolTip.IsOpen = true;
}