Qt计时器事件

protected:
    void timerEvent(QTimerEvent *e);

startTimer(1000);  // 单位毫秒

startTimer(1000);  // 一秒一次
startTimer(500);  // 500毫秒一次

int QObject::startTimer(int interval, Qt::TimerType timerType = Qt::CoarseTimer)  // 函数原型
// 说明
Starts a timer and returns a timer identifier, or returns zero if it could not start a timer.
A timer event will occur every interval milliseconds until killTimer() is called. If interval is 0, then the timer event occurs once every time there are no more window system events to process.
The virtual timerEvent() function is called with the QTimerEvent event parameter class when a timer event occurs. Reimplement this function to get timer events.
If multiple timers are running, the QTimerEvent::timerId() can be used to find out which timer was activated.

// 头文件
private:
    int timerID1;
    int timerID2;
// 构造函数
timerID1 = startTimer(1000);
timerID2 = startTimer(500);

// timerEvent事件

void MyWidget::timerEvent(QTimerEvent *e)
{
    static int i1 = 0;
    static int i2 = 0;
    if(e->timerId() == timerID1)
    {
        QString qs = QString("<center>i1: %1</center>").arg(++i1);
        ui->label->setText(qs);
        if(i1 == 3)
        {
            killTimer(timerID1);  // 关闭计时器
        }
    }
    else if(e->timerId() == timerID2)
    {
        QString qs = QString("<center>i1: %1</center>").arg(++i2);
        ui->label_2->setText(qs);
    }
}