Question

我遇到了问题，我可能正在将信号从一个QThread发送到另一个slot，但是我无法检查实现Qt::QueuedConnection的线程是否正在运行。框架在使用... WorkerImp* pWorker = new WorkerImp(); QThread worker; pWorker->moveToThread(&worker); QObject::connect(&worker, QThread::finished, pWorker, &QObject::deleteLater, Qt::QueuedConnection); bool connected = QObject::connect(this, &SlaveMaster::requireWork, pWorker, &WorkerImp::doWork, Qt::QueuedConnection); assert(connected); // at this point we have connected the signal, thread is not starded. // however the object that we use to connect still exists and will after we exit the thread. worker.start(); worker.exit(); worker.wait(); // note that when we exit the QThread we do not destroy the object - it can be start over emit requireWork(); ...时将如何处理这种情况？

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Answer 1

从不处理信号。线程之间的排队连接作为事件发布到线程，由事件循环处理。如果线程已停止（因此停止了其事件循环），则没有人可以拾取事件并将其传递：

来自Qt文档Signals and Slots Across Threads：

排队连接：当控制权返回到接收者线程的事件循环时，将调用该插槽。该插槽在接收者的线程中执行。

和Per-Thread Event Loop：

[...]如果没有运行任何事件循环，则事件不会传递到该对象。

请注意，阻塞的排队连接将死锁

Qt：向死线程/已停止线程发送信号

1 个答案: