protected override void OnPreviewMouseWheel(MouseWheelEventArgs e)
{
if (PopupManager.Tracking || IsPinning)
{
cumulativeWheelDelta += e.Delta;
if (Math.Abs(cumulativeWheelDelta) > MouseWheelSelectionChangeThreshold)
{
bool forward = cumulativeWheelDelta < 0;
cumulativeWheelDelta = 0;
IPopupItem selected = null;
if (PopupManager.Tracking)
{
if (PopupManager.HighlightedItem != null)
{
var p = PopupManager.HighlightedItem;
while (p.ParentItem != null)
{
p = p.ParentItem;
}
selected = p;
}
}
else
{
var item = PinnedItem;
selected = IsItemItsOwnContainer(item) ? (IPopupItem)item : (IPopupItem)ItemContainerGenerator.ContainerFromItem(item);
}
IPopupItem next = null;
if (selected != null)
{
next = selected
.PopupSiblings(forward, false)
.Where(x => PopupManager.Tracking || x is RibbonItem)
.FirstOrDefault();
}
else
{
next = this.PopupChildren()
.Where(x => PopupManager.Tracking || x is RibbonItem)
.FirstOrDefault();
}
if (next != null && next != selected)
{
e.Handled = true;
if (PopupManager.Tracking)
{
PopupManager.Enter(next, true);
}
else
{
PinnedItem = ItemContainerGenerator.ItemFromContainer((DependencyObject)next);
}
}
}
}
base.OnPreviewMouseWheel(e);
}
public static IPopupItem NavigateSibling(this IPopupItem item, bool forward, bool cycle)
{
return(item.PopupSiblings(forward, cycle).SelectableItem().FirstOrDefault().NavigateItem());
}