OS X上的单次QTimer快速发射多次且太早

Question

我在一个资源（类）上实现了一个空闲定时器，它的实例可以同时在多个应用程序中打开。因此，idleTimer不仅是简单的QTimer，而且时隙（触发器）需要验证在最后N分钟内是否没有其他应用程序访问相同的资源。如果是这种情况，则重置计时器（不更新lastAccessedTime值），否则关闭资源。因此，计时器是一个单次计时器，lastAccessTime保存在QSharedMemory对象中。

以下是一些跟踪输出：

### "Google Contacts () of type Google Contacts" Idle timeout 6 min. for KWallet::Wallet(0x105d1f900) "kdewallet" handle 0 ; elapsed minutes= 5.83601 timer QTimer(0x11d273d60) triggered 1 times 
### slotIdleTimedOut ->handleIdleTiming: setting QTimer(0x11d273d60) for wallet "kdewallet" handle 0 timeout to 6 
### "Google Contacts () of type Google Contacts" Idle timeout 6 min. for KWallet::Wallet(0x105d1f900) "kdewallet" handle 0 ;     elapsed minutes= 5.83634 timer QTimer(0x11d273d60) triggered 2 times 
### "Google Contacts () of type Google Contacts" Idle timeout 6 min. for KWallet::Wallet(0x105d1f900) "kdewallet" handle 0 ; elapsed minutes= 5.83634 timer QTimer(0x11d273d60) triggered 3 times 
### "Google Contacts ()of type Google Contacts" Idle timeout 6 min. for KWallet::Wallet(0x105d1f900) "kdewallet" handle 0 ; elapsed minutes= 5.83634 timer QTimer(0x11d273d60) triggered 4 times 
### "Google Contacts () of type Google Contacts" Idle timeout 6 min. for KWallet::Wallet(0x105d1f900) "kdewallet" handle 0 ; elapsed minutes= 5.83634 timer QTimer(0x11d273d60) triggered 5 times 
### "Google Contacts () of type Google Contacts" Idle timeout 6 min. for KWallet::Wallet(0x105d1f900) "kdewallet" handle 0 ; elapsed minutes= 5.83635 timer QTimer(0x11d273d60) triggered 6 times 
### "Google Contacts () of type Google Contacts" Idle timeout 6 min. for KWallet::Wallet(0x105d1f900) "kdewallet" handle 0 ;     elapsed minutes= 5.83635 timer QTimer(0x11d273d60) triggered 7 times 
### "Google Contacts () of type Google Contacts" Idle timeout 6 min. for KWallet::Wallet(0x105d1f900) "kdewallet" handle 0 ; elapsed minutes= 5.83635 timer QTimer(0x11d273d60) triggered 8 times 
### "KMail" Idle timeout 6 min. for KWallet::Wallet(0x1083f1ac0) "kdewallet" handle 0 ; elapsed minutes= 6 timer QTimer(0x120a1b5f0) triggered 1 times 
### "KMail" Idle timeout 6 min. for KWallet::Wallet(0x1083f1ac0) "kdewallet" handle -1 ; elapsed minutes= 6.00008 timer QObject(0x0)  triggered 2 times 
### "KMail" Idle timeout 6 min. for KWallet::Wallet(0x1083f1ac0) "kdewallet" handle -1 ; elapsed minutes= 6.00009 timer QObject(0x0)  triggered 3 times 
### "KMail" Idle timeout 6 min. for KWallet::Wallet(0x1083f1ac0) "kdewallet" handle -1 ; elapsed minutes= 6.00012 timer QObject(0x0)  triggered 4 times 
### "KMail" Idle timeout 6 min. for KWallet::Wallet(0x1083f1ac0) "kdewallet" handle -1 ; elapsed minutes= 6.00012 timer QObject(0x0)  triggered 5 times 
### "KMail" Idle timeout 6 min. for KWallet::Wallet(0x1083f1ac0) "kdewallet" handle -1 ; elapsed minutes= 6.00012 timer QObject(0x0)  triggered 6 times 
### "KMail" Idle timeout 6 min. for KWallet::Wallet(0x1083f1ac0) "kdewallet" handle -1 ; elapsed minutes= 6.00012 timer QObject(0x0)  triggered 7 times 
### "KMail" Idle timeout 6 min. for KWallet::Wallet(0x1083f1ac0) "kdewallet" handle -1 ; elapsed minutes= 6.00012 timer QObject(0x0)  triggered 8 times 

原理是有效的，但我注意到两件事：

• 计时器启动得有点早。当然，这会导致计时器重置
• 它连续几次快速开火。事实上，早期的火灾应该重置它并没有丝毫影响

下面是我的代码的相关部分，包括在每次资源访问时重置计时器的功能，以及计时器的触发槽。

知道我做错了什么吗？在将计时器重新设置为单次拍摄模式并重新启动之前，我先停止计时器。对象和应用程序标识符表明，它确实是同一个计时器，可以多次触发，即使在我删除计时器对象后，它也可以被触发。

触发槽是否不是特定于应用程序（甚至实例）的，以某种方式导致1个实例从设置该定时器实例的各种应用程序中的所有其他实例接收idleTimer触发信号？CCD_ 6仅在类析构函数中和/或当CCD_=0，所以我很难用NULL计时器对象调用我的触发器槽！

从定时器安装功能（handleIdleTiming，KWallet::Wallet的成员，也是idleTimer本身）：

// This function is to be called at every operation that is supposed to launch or reset
// the idle timing. @p timeOut is a time in minutes.
void handleIdleTiming(const char *caller="", bool touchAccessTime=true)
{
    // ...
    if( timeOut >= 0 ){
        if( !idleTimer ){
            idleTimer = new QTimer(0);
        }
        else{
            idleTimer->stop();
        }
        // when the idle timer fires, the wallet is supposed to be closed. There is thus
        // no reason to use a repeating timer.
        idleTimer->setSingleShot(true);
        connect( idleTimer, SIGNAL(timeout()), q, SLOT(slotIdleTimedOut()) );
        if( touchAccessTime ){
            if( lastAccessTime.lock() ){
                *((double*)lastAccessTime.data()) = HRTime_Time();
                lastAccessTime.unlock();
            }
            else{
                qDebug() << "Cannot lock lastAccessTime for wallet" << name << "error" << lastAccessTime.errorString();
            }
        }
        idleTimer->start( timeOut * 60 * 1000 );

定时器触发槽：

void Wallet::slotIdleTimedOut()
{   double lastAccessTime = 0;
    // check the last time anyone accessed this wallet:
    if( d->lastAccessTime.lock() ){
        lastAccessTime = *((double*)d->lastAccessTime.data());
        d->lastAccessTime.unlock();
    }
    else{
        qDebug() << "Cannot lock lastAccessTime for wallet" << d->name << "error" << d->lastAccessTime.errorString();
    }
    // the time elapsed since that last access, in minutes:
    double elapsed = (HRTime_Time() - lastAccessTime) / 60;
    d->idleTimerTriggered += 1;
    qDebug() << "###" << appid() << "Idle timeout" << d->timeOut << "min. for" << this << d->name << "handle" << d->handle
        << "; elapsed minutes=" << elapsed << "timer" << d->idleTimer << "triggered" << d->idleTimerTriggered << "times";
    if( elapsed >= d->timeOut ){
        // we have a true timeout, i.e. we didn't access the wallet in timeOut minutes, and no one else did either.
        slotWalletClosed(d->handle);
    }
    else{
        // false alarm, reset the timer, but there's no need to count this as an access!
        d->handleIdleTiming(__FUNCTION__, false);
    }
}

Answer 1

一定是因为我每次重置计时器时都会发出一条连接语句，而不是在创建计时器后只发出一次。