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c++qtqt4

Create a qstate in qt

If I have a simple state machine like that

  switch(state)
    {
    case state_1:
      doSomething();
    state = state_2;
    break;
    case state_2:
    doSomething_2();
state = state_finished;
    break;
    }

how would I convert this simple state machine into qstate with transitions ?

Solution

  • It would be for example something like this:

    TestClass test_class;
QStateMachine machine;

QState *state_1 = new QState(&machine);
QObject::connect(state_1, SIGNAL(entered()), &test_class, SLOT(doSomething1()));

QState *state_2 = new QState(&machine);
QObject::connect(state_2, SIGNAL(entered()), &test_class, SLOT(doSomething2()));

QFinalState *state_finished = new QFinalState(&machine);
TestClassFinishedTransition *finished_transition = 
                                new TestClassFinishedTransition(&test_class);
finished_transition->setTargetState(state_finished);
state_2->addTransition(finished_transition);

machine.setInitialState(state_1);
machine.start();

    TestClass would be QObject based class.

    I hope this piece of code helps you to get started in understanding the concept. However, you have to read the documentation carefully and go through examples provided by Qt.