qdeclarativeconnections.cpp

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#include "private/qdeclarativeconnections_p.h"

#include <qdeclarativeexpression.h>
#include <qdeclarativeproperty_p.h>
#include <qdeclarativeboundsignal_p.h>
#include <qdeclarativecontext.h>
#include <qdeclarativecontext_p.h>
#include <qdeclarativeinfo.h>

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

#include <private/qobject_p.h>

QT_BEGIN_NAMESPACE

class QDeclarativeConnectionsPrivate : public QObjectPrivate
{
public:
    QDeclarativeConnectionsPrivate() : target(0), targetSet(false), ignoreUnknownSignals(false), componentcomplete(true) {}

    QList<QDeclarativeBoundSignal*> boundsignals;
    QObject *target;

    bool targetSet;
    bool ignoreUnknownSignals;
    bool componentcomplete;

    QByteArray data;
};

QDeclarativeConnections::QDeclarativeConnections(QObject *parent) :
    QObject(*(new QDeclarativeConnectionsPrivate), parent)
{
}

QDeclarativeConnections::~QDeclarativeConnections()
{
}

QObject *QDeclarativeConnections::target() const
{
    Q_D(const QDeclarativeConnections);
    return d->targetSet ? d->target : parent();
}

void QDeclarativeConnections::setTarget(QObject *obj)
{
    Q_D(QDeclarativeConnections);
    d->targetSet = true; // even if setting to 0, it is *set*
    if (d->target == obj)
        return;
    foreach (QDeclarativeBoundSignal *s, d->boundsignals) {
        // It is possible that target is being changed due to one of our signal
        // handlers -> use deleteLater().
        if (s->isEvaluating())
            s->deleteLater();
        else
            delete s;
    }
    d->boundsignals.clear();
    d->target = obj;
    connectSignals();
    emit targetChanged();
}

bool QDeclarativeConnections::ignoreUnknownSignals() const
{
    Q_D(const QDeclarativeConnections);
    return d->ignoreUnknownSignals;
}

void QDeclarativeConnections::setIgnoreUnknownSignals(bool ignore)
{
    Q_D(QDeclarativeConnections);
    d->ignoreUnknownSignals = ignore;
}



QByteArray
QDeclarativeConnectionsParser::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());
        if (!propName.startsWith(QLatin1String("on")) || !propName.at(2).isUpper()) {
            error(props.at(ii), QDeclarativeConnections::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), QDeclarativeConnections::tr("Connections: nested objects not allowed"));
                return QByteArray();
            } else if (value.userType() == qMetaTypeId<QDeclarativeCustomParserProperty>()) {
                error(props.at(ii), QDeclarativeConnections::tr("Connections: syntax error"));
                return QByteArray();
            } else {
                QDeclarativeParser::Variant v = qvariant_cast<QDeclarativeParser::Variant>(value);
                if (v.isScript()) {
                    ds << propName;
                    ds << v.asScript();
                } else {
                    error(props.at(ii), QDeclarativeConnections::tr("Connections: script expected"));
                    return QByteArray();
                }
            }
        }
    }

    return rv;
}

void QDeclarativeConnectionsParser::setCustomData(QObject *object,
                                            const QByteArray &data)
{
    QDeclarativeConnectionsPrivate *p =
        static_cast<QDeclarativeConnectionsPrivate *>(QObjectPrivate::get(object));
    p->data = data;
}


void QDeclarativeConnections::connectSignals()
{
    Q_D(QDeclarativeConnections);
    if (!d->componentcomplete || (d->targetSet && !target()))
        return;

    QDataStream ds(d->data);
    while (!ds.atEnd()) {
        QString propName;
        ds >> propName;
        QString script;
        ds >> script;
        QDeclarativeProperty prop(target(), propName);
        if (prop.isValid() && (prop.type() & QDeclarativeProperty::SignalProperty)) {
            QDeclarativeBoundSignal *signal =
                new QDeclarativeBoundSignal(target(), prop.method(), this);
            QDeclarativeExpression *expression = new QDeclarativeExpression(qmlContext(this), 0, script);
            QDeclarativeData *ddata = QDeclarativeData::get(this);
            if (ddata && ddata->outerContext && !ddata->outerContext->url.isEmpty())
                expression->setSourceLocation(ddata->outerContext->url.toString(), ddata->lineNumber);
            signal->setExpression(expression);
            d->boundsignals += signal;
        } else {
            if (!d->ignoreUnknownSignals)
                qmlInfo(this) << tr("Cannot assign to non-existent property \"%1\"").arg(propName);
        }
    }
}

void QDeclarativeConnections::classBegin()
{
    Q_D(QDeclarativeConnections);
    d->componentcomplete=false;
}

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

QT_END_NAMESPACE