qtimer.cpp

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#include "qtimer.h"
#include "qabstracteventdispatcher.h"
#include "qcoreapplication.h"
#include "qobject_p.h"

QT_BEGIN_NAMESPACE

static const int INV_TIMER = -1;                // invalid timer id

QTimer::QTimer(QObject *parent)
    : QObject(parent), id(INV_TIMER), inter(0), del(0), single(0), nulltimer(0)
{
}


#ifdef QT3_SUPPORT

QTimer::QTimer(QObject *parent, const char *name)
    : QObject(parent), id(INV_TIMER), single(0), nulltimer(0)
{
    setObjectName(QString::fromAscii(name));
}
#endif

QTimer::~QTimer()
{
    if (id != INV_TIMER)                        // stop running timer
        stop();
}


void QTimer::start()
{
    if (id != INV_TIMER)                        // stop running timer
        stop();
    nulltimer = (!inter && single);
    id = QObject::startTimer(inter);
}

void QTimer::start(int msec)
{
    inter = msec;
    start();
}


#ifdef QT3_SUPPORT

int QTimer::start(int msec, bool sshot)
{
    if (id >=0 && nulltimer && !msec && sshot)
        return id;
    stop();
    setInterval(msec);
    setSingleShot(sshot);
    start();
    return timerId();
}
#endif


void QTimer::stop()
{
    if (id != INV_TIMER) {
        QObject::killTimer(id);
        id = INV_TIMER;
    }
}


void QTimer::timerEvent(QTimerEvent *e)
{
    if (e->timerId() == id) {
        if (single)
            stop();
        emit timeout();
    }
}

class QSingleShotTimer : public QObject
{
    Q_OBJECT
    int timerId;
public:
    ~QSingleShotTimer();
    QSingleShotTimer(int msec, QObject *r, const char * m);
Q_SIGNALS:
    void timeout();
protected:
    void timerEvent(QTimerEvent *);
};

QSingleShotTimer::QSingleShotTimer(int msec, QObject *receiver, const char *member)
    : QObject(QAbstractEventDispatcher::instance())
{
    connect(this, SIGNAL(timeout()), receiver, member);
    timerId = startTimer(msec);
}

QSingleShotTimer::~QSingleShotTimer()
{
    if (timerId > 0)
        killTimer(timerId);
}

void QSingleShotTimer::timerEvent(QTimerEvent *)
{
    // need to kill the timer _before_ we emit timeout() in case the
    // slot connected to timeout calls processEvents()
    if (timerId > 0)
        killTimer(timerId);
    timerId = -1;
    emit timeout();

    // we would like to use delete later here, but it feels like a
    // waste to post a new event to handle this event, so we just unset the flag
    // and explicitly delete...
    qDeleteInEventHandler(this);
}

QT_BEGIN_INCLUDE_NAMESPACE
#include "qtimer.moc"
QT_END_INCLUDE_NAMESPACE

void QTimer::singleShot(int msec, QObject *receiver, const char *member)
{
    if (receiver && member) {
        if (msec == 0) {
            // special code shortpath for 0-timers
            const char* bracketPosition = strchr(member, '(');
            if (!bracketPosition || !(member[0] >= '0' && member[0] <= '3')) {
                qWarning("QTimer::singleShot: Invalid slot specification");
                return;
            }
            QByteArray methodName(member+1, bracketPosition - 1 - member); // extract method name
            QMetaObject::invokeMethod(receiver, methodName.constData(), Qt::QueuedConnection);
            return;
        }
        (void) new QSingleShotTimer(msec, receiver, member);
    }
}

void QTimer::setInterval(int msec)
{
    inter = msec;
    if (id != INV_TIMER) {                        // create new timer
        QObject::killTimer(id);                        // restart timer
        id = QObject::startTimer(msec);
    }
}

QT_END_NAMESPACE