internal int FindZOrderIndex(StylusPlugInCollection spicAdding)
{
//should be called inside of lock(__rtiLock)
DependencyObject spicAddingVisual = spicAdding.Element as Visual;
int i;
for (i = 0; i < _plugInCollectionList.Count; i++)
{
// first see if parent of node, if it is then we can just scan till we find the
// first non parent and we're done
DependencyObject curV = _plugInCollectionList[i].Element as Visual;
if (VisualTreeHelper.IsAncestorOf(spicAddingVisual, curV))
{
i++;
while (i < _plugInCollectionList.Count)
{
curV = _plugInCollectionList[i].Element as Visual;
if (!VisualTreeHelper.IsAncestorOf(spicAddingVisual, curV))
{
break; // done
}
i++;
}
return(i);
}
else
{
// Look to see if spicAddingVisual is higher in ZOrder than i, if so then we're done
DependencyObject commonParent = VisualTreeHelper.FindCommonAncestor(spicAddingVisual, curV);
// If no common parent found then we must have multiple plugincollection elements
// that have been removed from the visual tree and we haven't been notified yet of
// that change. In this case just ignore this plugincollection element and go to
// the next.
if (commonParent == null)
{
continue;
}
// If curV is the commonParent we find then we're done. This new plugin should be
// above this one.
if (curV == commonParent)
{
return(i);
}
// now find first child for each under that common visual that these fall under (not they must be different or common parent is sort of busted.
while (VisualTreeHelper.GetParentInternal(spicAddingVisual) != commonParent)
{
spicAddingVisual = VisualTreeHelper.GetParentInternal(spicAddingVisual);
}
while (VisualTreeHelper.GetParentInternal(curV) != commonParent)
{
curV = VisualTreeHelper.GetParentInternal(curV);
}
// now see which is higher in zorder
int count = VisualTreeHelper.GetChildrenCount(commonParent);
for (int j = 0; j < count; j++)
{
DependencyObject child = VisualTreeHelper.GetChild(commonParent, j);
if (child == spicAddingVisual)
{
return(i);
}
else if (child == curV)
{
break; // look at next index in _piList.
}
}
}
}
return(i); // this wasn't higher so return last index.
}