private void FinalizeOrdering(FrameworkElement element)
{
_returnSite = null;
_mouseLockSite = null;
ReleaseOrderedSequence(element, _elements);
_elements = null;
}
private void ArrangeElements(ElementSite except)
{
var offset = 0.0;
foreach (var element in _elements)
{
if (element != except)
{
element.Offset = offset;
}
offset += element.Size;
}
}
public void OnOrderMove(FrameworkElement element, Vector delta)
{
var elementSite = GetActualSite(element);
var mousePosition = GetMousePosition(element);
elementSite.Position = elementSite.OriginalPosition.Offset((Point)delta);
if (_returnSite != null && _returnSite.Contains(mousePosition))
{
_elements.Swap(_returnSiteData.Item1, _returnSiteData.Item2);
ArrangeElements(elementSite);
_mouseLockSite = null;
_returnSite = null;
return;
}
if (_mouseLockSite != null && _mouseLockSite.Contains(mousePosition))
{
return;
}
_mouseLockSite = null;
var mouseSite = _elements.SingleOrDefault(e => e != elementSite && e.Contains(mousePosition));
if (mouseSite == null)
{
return;
}
_returnSite = GetArrangedElement(elementSite);
_returnSiteData = new Tuple <ElementSite, ElementSite>(mouseSite, elementSite);
_elements.Swap(elementSite, mouseSite);
ArrangeElements(elementSite);
_mouseLockSite = GetArrangedElement(mouseSite);
}
private ElementSite GetArrangedElement(ElementSite element)
{
return(new ElementSite(CalcElementOffset(_elements, element), element.Size, element.Orientation));
}
public double CalcElementOffset(List <ElementSite> elementSites, ElementSite element)
{
return(elementSites.TakeWhile(c => c != element).Sum(c => c.Size));
}