Qt线程之QThread

2024-03-02 05:20

文章标签 线程 qt qthread

本文主要是介绍Qt线程之QThread，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

线程创建

构造函数

public:explicit QThread(QObject *parent = nullptr);
protected:QThread(QThreadPrivate &dd, QObject *parent = nullptr);

线程优先级

枚举值有

IdlePriority
LowestPriority
LowPriority
NormalPriority
HighPriority
HighestPriority
TimeCriticalPriority
InheritPriority

enum Priority {IdlePriority,LowestPriority,LowPriority,NormalPriority,HighPriority,HighestPriority,TimeCriticalPriority,InheritPriority};class QThreadPrivate
{QThread::Priority priority;
}

设置优先级

void setPriority(Priority priority);

获取优先级

Priority priority() const;

线程运行状态

    bool isFinished() const;bool isRunning() const;
class QThreadPrivate 
{bool running;bool finished;bool isInFinish; //when in QThreadPrivate::finish
}

线程栈

    void setStackSize(uint stackSize);uint stackSize() const;
class QThreadPrivate 
{uint stackSize;
}

线程的事件分发器

QAbstractEventDispatcher *eventDispatcher() const;
void setEventDispatcher(QAbstractEventDispatcher *eventDispatcher);

线程的控制

public Q_SLOTS:void start(Priority = InheritPriority); //线程开启void terminate();//结束线程void quit();//结束线程的QEventLoop

线程的等待

bool wait(unsigned long time = ULONG_MAX);

QThread调用start具体做了哪些工作

创建线程执行QThreadPrivate的start方法
- 触发线程的started信号 emit thr->started(QThread::QPrivateSignal());
- 执行线程的默认run方法thr->run()
  - 执行exec方法
    - 执行事件循环，调用QEventLoop的exec

int QThread::exec()
{Q_D(QThread);QMutexLocker locker(&d->mutex);d->data->quitNow = false;if (d->exited) {d->exited = false;return d->returnCode;}locker.unlock();QEventLoop eventLoop;int returnCode = eventLoop.exec();locker.relock();d->exited = false;d->returnCode = -1;return returnCode;
}