rootNode->enableCategorizedDisplay();
rootNode->addItem("Child 1",QtilitiesCategory("Category 1"));
rootNode->addItem("Child 2",QtilitiesCategory("Category 1"));
rootNode->addItem("Child 3",QtilitiesCategory("Category 2"));
rootNode->addItem("Child 4",QtilitiesCategory("Category 2"));
rootNode->addItem("Child 5",QtilitiesCategory("Category 2"));

TreeWidget* categorized_widget = new TreeWidget(rootNode);
categorized_widget->show();
\endcode

Note that deep trees can be constructed by using different constru