src_corelib_thread_qthread.cpp

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** Copyright (C) 2016 Olivier Goffart <ogoffart@woboq.com>
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#include <QtCore/QThread>
class MyObject;
 
class WorkerThread : public QThread
{
    Q_OBJECT
    void run() override {
        QString result;
        /* ... here is the expensive or blocking operation ... */
        emit resultReady(result);
    }
signals:
    void resultReady(const QString &s);
};
 
void MyObject::startWorkInAThread()
{
    WorkerThread *workerThread = new WorkerThread(this);
    connect(workerThread, &WorkerThread::resultReady, this, &MyObject::handleResults);
    connect(workerThread, &WorkerThread::finished, workerThread, &QObject::deleteLater);
    workerThread->start();
}
 
 
class Worker : public QObject
{
    Q_OBJECT
 
public slots:
    void doWork(const QString &parameter) {
        QString result;
        /* ... here is the expensive or blocking operation ... */
        emit resultReady(result);
    }
 
signals:
    void resultReady(const QString &result);
};
 
class Controller : public QObject
{
    Q_OBJECT
    QThread workerThread;
public:
    Controller() {
        Worker *worker = new Worker;
        worker->moveToThread(&workerThread);
        connect(&workerThread, &QThread::finished, worker, &QObject::deleteLater);
        connect(this, &Controller::operate, worker, &Worker::doWork);
        connect(worker, &Worker::resultReady, this, &Controller::handleResults);
        workerThread.start();
    }
    ~Controller() {
        workerThread.quit();
        workerThread.wait();
    }
public slots:
    void handleResults(const QString &);
signals:
    void operate(const QString &);
};