QHistoryState

Use the setDefaultState() function to set the state that should be entered if the parent state has never been entered. Example:

 QStateMachine machine;

 QState *s1 = new QState();
 QState *s11 = new QState(s1);
 QState *s12 = new QState(s1);

 QHistoryState *s1h = new QHistoryState(s1);
 s1h->setDefaultState(s11);

 machine.addState(s1);

 QState *s2 = new QState();
 machine.addState(s2);

 QPushButton *button = new QPushButton();
 // Clicking the button will cause the state machine to enter the child state
 // that s1 was in the last time s1 was exited, or the history state's default
 // state if s1 has never been entered.
 s1->addTransition(button, SIGNAL(clicked()), s1h);

By default a history state is shallow, meaning that it won't remember nested states. This can be configured through the historyType property.