path: root/src/declarative/util/qmltimer.cpp

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#include "QtCore/qcoreapplication.h"
#include "QtCore/qpauseanimation.h"
#include "private/qobject_p.h"
#include "qmltimer.h"
#include "qdebug.h"

QT_BEGIN_NAMESPACE

QML_DEFINE_TYPE(Qt,4,6,(QT_VERSION&0x00ff00)>>8,Timer,QmlTimer)

class QmlTimerPrivate : public QObjectPrivate
{
    Q_DECLARE_PUBLIC(QmlTimer)
public:
    QmlTimerPrivate()
        : interval(1000), running(false), repeating(false), triggeredOnStart(false)
        , classBegun(false), componentComplete(false) {}
    int interval;
    bool running;
    bool repeating;
    bool triggeredOnStart;
    QPauseAnimation pause;
    bool classBegun;
    bool componentComplete;
};

/*!
    \qmlclass Timer QmlTimer
    \brief The Timer item triggers a handler at a specified interval.

    A timer can be used to trigger an action either once, or repeatedly
    at a given interval.

    \qml
    Timer {
        interval: 500; running: true; repeat: true
        onTriggered: time.text = Date().toString()
    }
    Text {
        id: time
    }
    \endqml

*/

QmlTimer::QmlTimer(QObject *parent)
    : QObject(*(new QmlTimerPrivate), parent)
{
    Q_D(QmlTimer);
    connect(&d->pause, SIGNAL(currentLoopChanged(int)), this, SLOT(ticked()));
    connect(&d->pause, SIGNAL(finished()), this, SLOT(ticked()));
    connect(&d->pause, SIGNAL(stateChanged(QAbstractAnimation::State,QAbstractAnimation::State))
            , this, SLOT(stateChanged(QAbstractAnimation::State,QAbstractAnimation::State)));
    d->pause.setLoopCount(1);
    d->pause.setDuration(d->interval);
}

/*!
    \qmlproperty int Timer::interval

    Sets the \a interval in milliseconds between triggering.

    The default interval is 1000 milliseconds.
*/
void QmlTimer::setInterval(int interval)
{
    Q_D(QmlTimer);
    if (interval != d->interval) {
        d->interval = interval;
        update();
    }
}

int QmlTimer::interval() const
{
    Q_D(const QmlTimer);
    return d->interval;
}

/*!
    \qmlproperty bool Timer::running

    If set to true, starts the timer; otherwise stops the timer.
    For a non-repeating timer, \a running  will be set to false after the
    timer has been triggered.

    \a running defaults to false.

    \sa repeat
*/
bool QmlTimer::isRunning() const
{
    Q_D(const QmlTimer);
    return d->running;
}

void QmlTimer::setRunning(bool running)
{
    Q_D(QmlTimer);
    if (d->running != running) {
        d->running = running;
        emit runningChanged();
        update();
    }
}

/*!
    \qmlproperty bool Timer::repeat

    If \a repeat is true the timer will be triggered repeatedly at the
    specified interval; otherwise, the timer will trigger once at the
    specified interval and then stop (i.e. running will be set to false).

    \a repeat defaults to false.

    \sa running
*/
bool QmlTimer::isRepeating() const
{
    Q_D(const QmlTimer);
    return d->repeating;
}

void QmlTimer::setRepeating(bool repeating)
{
    Q_D(QmlTimer);
    if (repeating != d->repeating) {
        d->repeating = repeating;
        update();
    }
}

/*!
    \qmlproperty bool Timer::triggeredOnStart

    If \a triggeredOnStart is true, the timer will be triggered immediately
    when started, and subsequently at the specified interval.  Note that for
    a Timer with \e repeat set to false, this will result in the timer being
    triggered twice; once on start, and again at the interval.

    \a triggeredOnStart defaults to false.

    \sa running
*/
bool QmlTimer::triggeredOnStart() const
{
    Q_D(const QmlTimer);
    return d->triggeredOnStart;
}

void QmlTimer::setTriggeredOnStart(bool triggeredOnStart)
{
    Q_D(QmlTimer);
    if (d->triggeredOnStart != triggeredOnStart) {
        d->triggeredOnStart = triggeredOnStart;
        update();
    }
}

/*!
    \qmlmethod Timer::start()
    \brief Starts the timer.

    If the timer is already running, calling this method has no effect.  The
    \c running property will be true following a call to \c start().
*/
void QmlTimer::start()
{
    setRunning(true);
}

/*!
    \qmlmethod Timer::stop()
    \brief stops the timer.

    If the timer is not running, calling this method has no effect.  The
    \c running property will be false following a call to \c stop().
*/
void QmlTimer::stop()
{
    setRunning(false);
}

void QmlTimer::update()
{
    Q_D(QmlTimer);
    if (d->classBegun && !d->componentComplete)
        return;
    d->pause.stop();
    if (d->running) {
        d->pause.setLoopCount(d->repeating ? -1 : 1);
        d->pause.setDuration(d->interval);
        d->pause.start();
        if (d->triggeredOnStart) {
            QCoreApplication::removePostedEvents(this, QEvent::MetaCall);
            QMetaObject::invokeMethod(this, "ticked", Qt::QueuedConnection);
        }
    }
}

void QmlTimer::classBegin()
{
    Q_D(QmlTimer);
    d->classBegun = true;
}

void QmlTimer::componentComplete()
{
    Q_D(QmlTimer);
    d->componentComplete = true;
    update();
}

/*!
    \qmlsignal Timer::onTriggered

    This handler is called when the Timer is triggered.
*/
void QmlTimer::ticked()
{
    emit triggered();
}

void QmlTimer::stateChanged(QAbstractAnimation::State, QAbstractAnimation::State state)
{
    Q_D(QmlTimer);
    if (d->running && state != QAbstractAnimation::Running) {
        d->running = false;
        emit runningChanged();
    }
}

QT_END_NAMESPACE