Qt实现信号灯

//设置背景颜色，椭圆弧度
ui->radioButton->setStyleSheet("QRadioButton::indicator{width:35px;height:35px;border-radius:17px}"
"QRadioButton::indicator:checked{background-color:green;}"
"QRadioButton::indicator:unchecked{background-color:red;}");

QVBoxLayout *vbox = new QVBoxLayout(this);
TrafficLightWidget *widget = new TrafficLightWidget();
vbox->addWidget(widget);
vbox->setMargin(0);

QStateMachine *machine = new QStateMachine(this);
QState *redGoingYellow = createLightState(widget->redLight(), 3000);
redGoingYellow->setObjectName("redGoingYellow");
QState *yellowGoingGreen = createLightState(widget->yellowLight(), 1000);
yellowGoingGreen->setObjectName("yellowGoingGreen");
redGoingYellow->addTransition(redGoingYellow, SIGNAL(finished()), yellowGoingGreen);
QState *greenGoingYellow = createLightState(widget->greenLight(), 3000);
greenGoingYellow->setObjectName("greenGoingYellow");
yellowGoingGreen->addTransition(yellowGoingGreen, SIGNAL(finished()), greenGoingYellow);
QState *yellowGoingRed = createLightState(widget->yellowLight(), 1000);
yellowGoingRed->setObjectName("yellowGoingRed");
greenGoingYellow->addTransition(greenGoingYellow, SIGNAL(finished()), yellowGoingRed);
yellowGoingRed->addTransition(yellowGoingRed, SIGNAL(finished()), redGoingYellow);

machine->addState(redGoingYellow);
machine->addState(yellowGoingGreen);
machine->addState(greenGoingYellow);
machine->addState(yellowGoingRed);
machine->setInitialState(redGoingYellow);
machine->start();