The QWaitCondition class provides a condition variable for synchronizing threads.
QWaitCondition allows a thread to tell other threads that some sort of condition has been met. One or many threads can block waiting for a QWaitCondition to set a condition with wakeOne() or wakeAll(). Use wakeOne() to wake one randomly selected condition or wakeAll() to wake them all.
我猜测Qt之所以不使用resume和suspend多少是因为参考了java里的Thread的resume和suspend(java里这2个方法已经不被建议使用了-deprected),使用resume和suspend有“死锁倾向”