我有以下类(class):
class MainWindow : public QMainWindow
{
public:
void StartTimer()
{
timer = new QTimer(this);
timer.start(100);
}
private:
QTimer *timer;
};
class AnotherClass
{
public:
MainWindow *window;
void runTimer()
{
window->StartTimer();
}
};
假设窗口指针正确指向主窗口,如果我尝试调用 runTimer()
,我会收到此错误:
QObject: Cannot create children for a parent that is in a different thread.
(Parent is MainWindow(0x7fff51ffe9f0), parent's thread is QThread(0x7fd1c8d001d0), current thread is QThread(0x7fd1c8f870c0)
QObject::startTimer: Timers can only be used with threads started with QThread
我对这个错误的猜测是因为 runTimer 是从不同的线程调用的,所以它也在尝试在同一个线程中初始化?而不是主窗口线程?
如果我在接收到的主窗口的默认构造函数中初始化计时器
QObject::startTimer: Timers cannot be started from another thread
如何让 QTimer 从另一个类开始?
最佳答案
您可以使用信号和槽。
class AnotherClass : public QObject
{
Q_OBJECT
public:
MainWindow * window;
AnotherClass() : window( new MainWindow )
{
// Connect signal to slot (or just normal function, in this case )
connect( this, &AnotherClass::signalStartTimer,
window, &MainWindow::StartTimer,
// This ensures thread safety, usually the default behavior, but it doesn't hurt to be explicit
Qt::QueuedConnection );
runTimer();
}
void runTimer()
{
emit signalStartTimer();
}
signals:
void signalStartTimer();
};
关于c++ - 从另一个类启动 QTimer,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/37222069/