关于 qt:QObject::startTimer：定时器只能用于以 QThread 启动的线程

QObject::startTimer: Timers can only be used with threads started with QThread

我正在尝试在工作线程的事件循环中启动 Timer，但出现此错误：
QObject::startTimer: Timers can only be used with threads started with QThread

这有什么问题吗？

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#include <QObject>
#include <QThread>
#include <QTimer>

class A : public QObject
{
Q_OBJECT
public:
A();

private:
QThread m_workerThread;
QTimer m_myTimer;

};

A::A()
{
this->moveToThread(&m_workerThread);
m_myTimer.moveToThread(&m_workerThread);
m_workerThread.start();
m_myTimer.start(1000);
}

在任何地方初始化你的计时器，但在线程启动时立即启动它(将它附加到 QThread::started 信号)：

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class A : public QObject
{
Q_OBJECT
public:
A();

private slots:
void started();
void timeout();

private:
QThread m_workerThread;
QTimer m_myTimer;
};

A::A()
{
moveToThread(&m_workerThread);

connect(&m_workerThread, SIGNAL(started()), this, SLOT(started()));
connect(&m_myTimer, SIGNAL(timeout()), this, SLOT(timeout()));

m_myTimer.setInterval(1000);
m_myTimer.moveToThread(&m_workerThread);

m_workerThread.start();
}

void A::started()
{
timer.start();
}

void A::timeout()
{
// timer handler
}

我想我想通了，我尝试从 GUI 线程启动计时器，在我将它移到工作线程之后，它似乎可以工作：

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class A : public QObject
{
Q_OBJECT
public:
A();

private:
QThread m_workerThread;
QTimer m_myTimer;

public slots:
void sl_startTimer();
};

A::A()
{
this->moveToThread(&m_workerThread);
m_myTimer.moveToThread(&m_workerThread);
m_workerThread.start();
QMetaObject::invokeMethod(this,"sl_startTimer", Qt::QueuedConnection);
}

void A::sl_startTimer()
{
m_myTimer.start(1000);
}

相关讨论

希望这会有所帮助：

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class ReadYoloResult : public QObject
{
Q_OBJECT
public:
ReadYoloResult(QObject *parent = 0);
void startTimer();
QThread workerThread;

private:
QTimer *timer;

public slots:
void timerSlot();
};

ReadYoloResult::ReadYoloResult(QObject * parent)
{
this->moveToThread(&workerThread);
timer = new QTimer();
connect(timer,SIGNAL(timeout()),this,SLOT(timerSlot()));

workerThread.start();

//timer->start(1000);
}

void ReadYoloResult::startTimer(){
timer->start(100);
}
void ReadYoloResult::timerSlot(){
qDebug()<<"In timer slot";
}

这种方法对我来说似乎有点危险。通过将 QObject 移动到 QThread 上，您正在使线程负责对象的事件(信号、槽、消息等)。但是，当对象被删除时，线程将在对象本身之前被删除，这可能会导致一些意想不到的行为。

推荐的做法是分别实例化线程和对象。