MyClass myObject;QFutureWatcher watcher;connect(&watcher, SIGNAL(finished()), &myObject, SLOT(handleFinished()));
// Start the computation.QFuture future = QtConcurrent::run(...);watcher.setFuture(future);
发送信号finished()的线程是谁？是 run的新线程，还是watcher当前所在线程？不是很理解。书里面也没讲。