目錄

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基本概念

代碼與實例

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基本概念

這里有個官方例子，如下：

class WorkerThread : public QThread{Q_OBJECTvoid 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();}

從官方的例子中可以看到，在run里面emit，但是，如果要在run里面進行如果要new一個QTimer，這樣就要啟動事件exec()，不然信號會發(fā)不出的，如下：

void TransformThread::run() {m_timeLine->start();QTimer *t = new QTimer;connect(t, SIGNAL(timeout()), this, SLOT(timeOutTest()));t->start(100);exec(); }

通過這樣的代碼就可以實現(xiàn)。

在QThread的構造函數(shù)中new()的對象，這個對象的創(chuàng)建在QThread被new的線程里面，

而在構造函數(shù)后面創(chuàng)建的對象，就在Thread中線程。

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代碼與實例

如下QThread代碼

transformthread.h

#ifndef TRANSFORMTHREAD_H #define TRANSFORMTHREAD_H#include <QThread> #include <QList>QT_BEGIN_NAMESPACE class QGraphicsItem; class QTimeLine; QT_END_NAMESPACEclass TransformThread : public QThread {Q_OBJECT public:TransformThread(QObject *object = nullptr);~TransformThread();void run();void addListItem(QGraphicsItem *item);void closeThread();public slots:void transformWay1(int value);void transformFinished();void timeOutTest();private:QList<QGraphicsItem*> m_list;bool m_isRun;QTimeLine *m_timeLine;bool m_newTime; };#endif // TRANSFORMTHREAD_H

transformthread.cpp

#include "transformthread.h" #include <QPointF> #include <QTransform> #include <QGraphicsItem> #include <QPushButton> #include <QTimeLine> #include <QDebug> #include <QTimer>TransformThread::TransformThread(QObject *object):QThread(object) {m_isRun = true;m_newTime = true;m_timeLine = nullptr; }TransformThread::~TransformThread() {delete m_timeLine; }void TransformThread::run() {while(m_isRun){//qDebug() << "123456";if(m_newTime){m_timeLine = new QTimeLine(500);m_timeLine->setFrameRange(0, 500);qDebug() << "123";connect(m_timeLine, SIGNAL(frameChanged(int)), this, SLOT(transformWay1(int)), Qt::DirectConnection);connect(m_timeLine, SIGNAL(finished()), this, SLOT(transformFinished()), Qt::DirectConnection);m_newTime = false;m_timeLine->start();//QTimer *t = new QTimer;//connect(t, SIGNAL(timeout()), this, SLOT(timeOutTest()));//t->start(100);exec();}//QThread::sleep(1);} }void TransformThread::addListItem(QGraphicsItem *item) {m_list << item; }void TransformThread::closeThread() {m_isRun = false; }void TransformThread::transformWay1(int value) {qDebug() << "value: " << value;if(m_list.size() == 0)return;for(int i = 0; i < m_list.size(); i++){QPointF pt = m_list[i]->boundingRect().center();qreal angle = value / 2.0;QTransform transform;transform.translate(pt.x(), pt.y());transform.rotate(angle, Qt::XAxis);m_list[i]->setTransform(transform);}}void TransformThread::transformFinished() {delete m_timeLine;m_newTime = true; }void TransformThread::timeOutTest() {qDebug() << "11111111111111"; }

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