1. QObject::startTimer

int QObject::startTimer(int interval, Qt::TimerType timerType = Qt::CoarseTimer)
int QObject::startTimer(std::chrono::milliseconds time, Qt::TimerType timerType = Qt::CoarseTimer)

每次时间到了会调用虚函数timerEvent()

2. QTimer

3. QBasicTimer

参考

• Qt帮助文档：
  The QTimer class provides a high-level programming interface with single-shot timers and timer signals instead of events. There is also a QBasicTimer class that is more lightweight than QTimer and less clumsy than using timer IDs directly.