Using inherited Groups

This code sample uses the attributes from the preceding examples. It shows you how to create groups that can be inherited, handle change notification, and manipulate group hierarchies.

  TInheritableGroupHandle grandParent;
  TInheritableGroupHandle parent;
  TInheritableGroupHandle child;
  
  // The next call causes NotifyChanged to be called on child, since its
  // hierarchy changed.
  child.SetParent(&parent);
  
  // The next call causes NotifyChanged to be called on both parent and child,
  // since the hierarchy changed for them both.
  parent.SetParent(&grandParent);
  
  // The next call causes NotifyChanged() to be called on grandParent, parent
  // and child.
  grandParent.Add(oneA);
  
  // The next call begins change batching for child and its ancestors.
  // That is, changes to child, parent, or grandParent does not result in
  // NotifyChanged() being called on any of these.
  child.BeginChanges();
  
  parent.Add(twoB);
  child.Add(oneC);
  
  count = grandParent.Count();            // Should be 1.
  count = grandParent.CountAllInherited(); // Should be 1.
  count = parent.Count();                 // Should be 1.
  count = parent.CountAllInherited();     // Should be 2.
  count = child.Count();                  // Should be 1.
  count = child.CountAllInherited();      // Should be 2, child's "one C" overrides 
                                          // grandparent's "one A".
  
  // The next call causes NotifyChanged() to be called on "child," 
  // "parent," and "grandParent."
  // Note that you must call EndChanges() on the same instance that you called 
  // BeginChanges() on.
  child.EndChanges();