public override IDropLocation GetDropLocation(Point cursor)
{
StackPanelDropLocation dropTarget = GetDropLocationCore(cursor);
if (dropTarget != null && dropTarget.IsNearby())
{
dropTarget = null;
}
return(dropTarget);
}
private StackPanelDropLocation GetDropLocationCore(Point cursor)
{
StackPanelDropLocation dropTarget = null;
if (DragManager.DraggedElement.IsElementInSubtree(this))
{
return(null);
}
if (Children.Count == 0)
{
dropTarget = new StackPanelDropLocation(
this,
0,
PointSituationRelativeToRect.Fill,
GetMarkerCoordinates(new Rect(), true));
}
int i = 0;
foreach (FrameworkElement child in Children)
{
var classification = ClassifyPoint(cursor, childPositions[i]);
if (classification == PointSituationRelativeToRect.Before)
{
dropTarget = new StackPanelDropLocation(this, i, classification, GetMarkerCoordinates(childPositions[i], true));
return(dropTarget);
}
if (i == Children.Count - 1 && classification == PointSituationRelativeToRect.After)
{
dropTarget = new StackPanelDropLocation(this, i, classification, GetMarkerCoordinates(childPositions[i], false));
return(dropTarget);
}
i++;
}
return(dropTarget);
}