qdeclarativegesturearea.cpp

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#include "qdeclarativegesturearea_p.h"

#include <qdeclarativeexpression.h>
#include <qdeclarativecontext.h>
#include <qdeclarativeinfo.h>

#include <private/qdeclarativeproperty_p.h>
#include <private/qdeclarativeitem_p.h>

#include <QtCore/qdebug.h>
#include <QtCore/qstringlist.h>

#include <QtGui/qevent.h>

#include <private/qobject_p.h>

#ifndef QT_NO_GESTURES

QT_BEGIN_NAMESPACE

class QDeclarativeGestureAreaPrivate : public QDeclarativeItemPrivate
{
    Q_DECLARE_PUBLIC(QDeclarativeGestureArea)
public:
    QDeclarativeGestureAreaPrivate() : componentcomplete(false), gesture(0) {}

    typedef QMap<Qt::GestureType,QDeclarativeExpression*> Bindings;
    Bindings bindings;

    bool componentcomplete;

    QByteArray data;

    QGesture *gesture;

    bool gestureEvent(QGestureEvent *event);
};

QDeclarativeGestureArea::QDeclarativeGestureArea(QDeclarativeItem *parent) :
    QDeclarativeItem(*(new QDeclarativeGestureAreaPrivate), parent)
{
    setAcceptedMouseButtons(Qt::LeftButton);
    setAcceptTouchEvents(true);
}

QDeclarativeGestureArea::~QDeclarativeGestureArea()
{
}

QByteArray
QDeclarativeGestureAreaParser::compile(const QList<QDeclarativeCustomParserProperty> &props)
{
    QByteArray rv;
    QDataStream ds(&rv, QIODevice::WriteOnly);

    for(int ii = 0; ii < props.count(); ++ii)
    {
        QString propName = QString::fromUtf8(props.at(ii).name());
        Qt::GestureType type;

        if (propName == QLatin1String("onTap")) {
            type = Qt::TapGesture;
        } else if (propName == QLatin1String("onTapAndHold")) {
            type = Qt::TapAndHoldGesture;
        } else if (propName == QLatin1String("onPan")) {
            type = Qt::PanGesture;
        } else if (propName == QLatin1String("onPinch")) {
            type = Qt::PinchGesture;
        } else if (propName == QLatin1String("onSwipe")) {
            type = Qt::SwipeGesture;
        } else if (propName == QLatin1String("onGesture")) {
            type = Qt::CustomGesture;
        } else {
            error(props.at(ii), QDeclarativeGestureArea::tr("Cannot assign to non-existent property \"%1\"").arg(propName));
            return QByteArray();
        }

        QList<QVariant> values = props.at(ii).assignedValues();

        for (int i = 0; i < values.count(); ++i) {
            const QVariant &value = values.at(i);

            if (value.userType() == qMetaTypeId<QDeclarativeCustomParserNode>()) {
                error(props.at(ii), QDeclarativeGestureArea::tr("GestureArea: nested objects not allowed"));
                return QByteArray();
            } else if (value.userType() == qMetaTypeId<QDeclarativeCustomParserProperty>()) {
                error(props.at(ii), QDeclarativeGestureArea::tr("GestureArea: syntax error"));
                return QByteArray();
            } else {
                QDeclarativeParser::Variant v = qvariant_cast<QDeclarativeParser::Variant>(value);
                if (v.isScript()) {
                    ds << propName;
                    ds << int(type);
                    ds << v.asScript();
                } else {
                    error(props.at(ii), QDeclarativeGestureArea::tr("GestureArea: script expected"));
                    return QByteArray();
                }
            }
        }
    }

    return rv;
}

void QDeclarativeGestureAreaParser::setCustomData(QObject *object,
                                            const QByteArray &data)
{
    QDeclarativeGestureArea *ga = static_cast<QDeclarativeGestureArea*>(object);
    ga->d_func()->data = data;
}


void QDeclarativeGestureArea::connectSignals()
{
    Q_D(QDeclarativeGestureArea);
    if (!d->componentcomplete)
        return;

    QDataStream ds(d->data);
    while (!ds.atEnd()) {
        QString propName;
        ds >> propName;
        int gesturetype;
        ds >> gesturetype;
        QString script;
        ds >> script;
        QDeclarativeExpression *exp = new QDeclarativeExpression(qmlContext(this), this, script);
        d->bindings.insert(Qt::GestureType(gesturetype),exp);
        grabGesture(Qt::GestureType(gesturetype));
    }
}

void QDeclarativeGestureArea::componentComplete()
{
    QDeclarativeItem::componentComplete();
    Q_D(QDeclarativeGestureArea);
    d->componentcomplete=true;
    connectSignals();
}

QGesture *QDeclarativeGestureArea::gesture() const
{
    Q_D(const QDeclarativeGestureArea);
    return d->gesture;
}

bool QDeclarativeGestureArea::sceneEvent(QEvent *event)
{
    Q_D(QDeclarativeGestureArea);
    if (event->type() == QEvent::Gesture)
        return d->gestureEvent(static_cast<QGestureEvent*>(event));
    return QDeclarativeItem::sceneEvent(event);
}

bool QDeclarativeGestureAreaPrivate::gestureEvent(QGestureEvent *event)
{
    bool accept = true;
    for (Bindings::Iterator it = bindings.begin(); it != bindings.end(); ++it) {
        if ((gesture = event->gesture(it.key()))) {
            QDeclarativeExpression *expr = it.value();
            expr->evaluate();
            if (expr->hasError())
                qmlInfo(q_func()) << expr->error();
            event->setAccepted(true); // XXX only if value returns true?
        }
    }
    return accept;
}

QT_END_NAMESPACE

#endif // QT_NO_GESTURES