/// <summary>
/// Change the <see cref="P:Northwoods.Go.GoObject.Parent" /> of an object to be the common subgraph that
/// contains two given objects, or if there is no such subgraph, add the object to the given layer.
/// </summary>
/// <param name="obj">the <see cref="T:Northwoods.Go.GoObject" /> to reparent</param>
/// <param name="child1">an object that may belong to a <see cref="T:Northwoods.Go.GoSubGraphBase" /></param>
/// <param name="child2">another object that may belong to a <see cref="T:Northwoods.Go.GoSubGraphBase" /></param>
/// <param name="behind">whether to add the <paramref name="obj" /> at the beginning of the list
/// of the subgraph's children (thus behind all other subgraph children), or at the end of the list
/// (thus appearing in front of all the other subgraph children)</param>
/// <param name="layer">
/// the <see cref="T:Northwoods.Go.GoLayer" /> to which the <paramref name="obj" /> should be added,
/// if there is no common parent <see cref="T:Northwoods.Go.GoSubGraphBase" /> for <paramref name="child1" /> and
/// <paramref name="child2" />
/// </param>
/// <remarks>
/// All of the arguments to this method should be non-null.
/// </remarks>
public static void ReparentToCommonSubGraph(GoObject obj, GoObject child1, GoObject child2, bool behind, GoLayer layer)
{
GoSubGraphBase a = FindParentSubGraph(child1);
GoSubGraphBase b = FindParentSubGraph(child2);
GoObject goObject = GoObject.FindCommonParent(a, b);
while (goObject != null && !(goObject is GoSubGraphBase))
{
goObject = goObject.Parent;
}
GoSubGraphBase goSubGraphBase = goObject as GoSubGraphBase;
if (obj.Parent == goSubGraphBase && obj.Layer != null)
{
return;
}
if (obj.Parent == null && obj.Layer == null)
{
if (goSubGraphBase != null)
{
if (behind)
{
goSubGraphBase.InsertBefore(null, obj);
}
else
{
goSubGraphBase.InsertAfter(null, obj);
}
}
else
{
layer.Add(obj);
}
}
else
{
GoCollection goCollection = new GoCollection();
goCollection.Add(obj);
if (goSubGraphBase != null)
{
goSubGraphBase.AddCollection(goCollection, reparentLinks: false);
}
else
{
layer.AddCollection(goCollection, reparentLinks: false);
}
}
}
/// <summary>
/// Unlike the standard behavior provided by <see cref="T:Northwoods.Go.GoGroup" />'s <see cref="M:Northwoods.Go.GoGroup.PickObjects(System.Drawing.PointF,System.Boolean,Northwoods.Go.IGoCollection,System.Int32)" />,
/// subgraphs allow the picking of more than one child, if they overlap each other at the given point.
/// </summary>
/// <param name="p"></param>
/// <param name="selectableOnly"></param>
/// <param name="coll"></param>
/// <param name="max"></param>
/// <returns></returns>
/// <remarks>
/// If <see cref="M:Northwoods.Go.GoObject.CanView" /> is false for this group, no children are added to the collection.
/// </remarks>
public override IGoCollection PickObjects(PointF p, bool selectableOnly, IGoCollection coll, int max)
{
if (coll == null)
{
coll = new GoCollection();
}
if (coll.Count >= max)
{
return(coll);
}
if (!GoObject.ContainsRect(Bounds, p))
{
return(coll);
}
if (!CanView())
{
return(coll);
}
foreach (GoObject backward in base.Backwards)
{
GoSubGraphBase goSubGraphBase = backward as GoSubGraphBase;
if (goSubGraphBase != null)
{
goSubGraphBase.PickObjects(p, selectableOnly, coll, max);
}
else
{
GoObject goObject = backward.Pick(p, selectableOnly);
if (goObject != null)
{
coll.Add(goObject);
if (coll.Count >= max)
{
return(coll);
}
}
}
}
if (PickableBackground && (!selectableOnly || CanSelect()))
{
coll.Add(this);
}
return(coll);
}
