 of the Qtilities::Core::Observer class is that it supports the grouping of objects within the context into categories. Lets change our example again by adding intended categories for objects that we attach to \p nodeB.

\code
nodeB->enableCategorizedDisplay();
nodeB->addItem("Child 5",QtilitiesCategory("Category 1"));
nodeB->addItem("Child 6",QtilitiesCategory("Category 2"));
nodeB->addItem("Child 7",QtilitiesCategory("Category 2"));
\endcode

These changes will result in the observer widget shown below (i