qdeclarativecomponent.cpp

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** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
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#include "qdeclarativecomponent.h"
#include "private/qdeclarativecomponent_p.h"

#include "private/qdeclarativecompiler_p.h"
#include "private/qdeclarativecontext_p.h"
#include "private/qdeclarativeengine_p.h"
#include "private/qdeclarativevme_p.h"
#include "qdeclarative.h"
#include "qdeclarativeengine.h"
#include "private/qdeclarativebinding_p.h"
#include "private/qdeclarativebinding_p_p.h"
#include "private/qdeclarativeglobal_p.h"
#include "private/qdeclarativescriptparser_p.h"
#include "private/qdeclarativedebugtrace_p.h"
#include "private/qdeclarativeenginedebugservice_p.h"
#include <QtScript/qscriptvalueiterator.h>

#include <QStack>
#include <QStringList>
#include <QtCore/qdebug.h>
#include <QApplication>
#include <qdeclarativeinfo.h>

QT_BEGIN_NAMESPACE

class QByteArray;

void QDeclarativeComponentPrivate::typeDataReady(QDeclarativeTypeData *)
{
    Q_Q(QDeclarativeComponent);

    Q_ASSERT(typeData);

    fromTypeData(typeData);
    typeData = 0;

    emit q->statusChanged(q->status());
}

void QDeclarativeComponentPrivate::typeDataProgress(QDeclarativeTypeData *, qreal p)
{
    Q_Q(QDeclarativeComponent);

    progress = p;

    emit q->progressChanged(p);
}

void QDeclarativeComponentPrivate::fromTypeData(QDeclarativeTypeData *data)
{
    url = data->finalUrl();
    QDeclarativeCompiledData *c = data->compiledData();

    if (!c) {
        Q_ASSERT(data->isError());
        state.errors = data->errors();
    } else {
        cc = c;
    }

    data->release();
}

void QDeclarativeComponentPrivate::clear()
{
    if (typeData) {
        typeData->unregisterCallback(this);
        typeData->release();
        typeData = 0;
    }

    if (cc) {
        cc->release();
        cc = 0;
    }
}

QDeclarativeComponent::QDeclarativeComponent(QObject *parent)
    : QObject(*(new QDeclarativeComponentPrivate), parent)
{
}

QDeclarativeComponent::~QDeclarativeComponent()
{
    Q_D(QDeclarativeComponent);

    if (d->state.completePending) {
        qWarning("QDeclarativeComponent: Component destroyed while completion pending");
        d->completeCreate();
    }

    if (d->typeData) {
        d->typeData->unregisterCallback(d);
        d->typeData->release();
    }
    if (d->cc)
        d->cc->release();
}

QDeclarativeComponent::Status QDeclarativeComponent::status() const
{
    Q_D(const QDeclarativeComponent);

    if (d->typeData)
        return Loading;
    else if (!d->state.errors.isEmpty())
        return Error;
    else if (d->engine && d->cc)
        return Ready;
    else
        return Null;
}

bool QDeclarativeComponent::isNull() const
{
    return status() == Null;
}

bool QDeclarativeComponent::isReady() const
{
    return status() == Ready;
}

bool QDeclarativeComponent::isError() const
{
    return status() == Error;
}

bool QDeclarativeComponent::isLoading() const
{
    return status() == Loading;
}

qreal QDeclarativeComponent::progress() const
{
    Q_D(const QDeclarativeComponent);
    return d->progress;
}

QDeclarativeComponent::QDeclarativeComponent(QDeclarativeEngine *engine, QObject *parent)
    : QObject(*(new QDeclarativeComponentPrivate), parent)
{
    Q_D(QDeclarativeComponent);
    d->engine = engine;
}

QDeclarativeComponent::QDeclarativeComponent(QDeclarativeEngine *engine, const QUrl &url, QObject *parent)
: QObject(*(new QDeclarativeComponentPrivate), parent)
{
    Q_D(QDeclarativeComponent);
    d->engine = engine;
    loadUrl(url);
}

QDeclarativeComponent::QDeclarativeComponent(QDeclarativeEngine *engine, const QString &fileName,
                           QObject *parent)
: QObject(*(new QDeclarativeComponentPrivate), parent)
{
    Q_D(QDeclarativeComponent);
    d->engine = engine;
    loadUrl(d->engine->baseUrl().resolved(QUrl::fromLocalFile(fileName)));
}

QDeclarativeComponent::QDeclarativeComponent(QDeclarativeEngine *engine, QDeclarativeCompiledData *cc, int start, int count, QObject *parent)
    : QObject(*(new QDeclarativeComponentPrivate), parent)
{
    Q_D(QDeclarativeComponent);
    d->engine = engine;
    d->cc = cc;
    cc->addref();
    d->start = start;
    d->count = count;
    d->url = cc->url;
    d->progress = 1.0;
}

void QDeclarativeComponent::setData(const QByteArray &data, const QUrl &url)
{
    Q_D(QDeclarativeComponent);

    d->clear();

    d->url = url;

    QDeclarativeTypeData *typeData = QDeclarativeEnginePrivate::get(d->engine)->typeLoader.get(data, url);

    if (typeData->isCompleteOrError()) {
        d->fromTypeData(typeData);
    } else {
        d->typeData = typeData;
        d->typeData->registerCallback(d);
    }

    d->progress = 1.0;
    emit statusChanged(status());
    emit progressChanged(d->progress);
}

QDeclarativeContext *QDeclarativeComponent::creationContext() const
{
    Q_D(const QDeclarativeComponent);
    if(d->creationContext)
        return d->creationContext->asQDeclarativeContext();

    return qmlContext(this);
}

void QDeclarativeComponent::loadUrl(const QUrl &url)
{
    Q_D(QDeclarativeComponent);

    d->clear();

    if ((url.isRelative() && !url.isEmpty())
    || url.scheme() == QLatin1String("file")) // Workaround QTBUG-11929
        d->url = d->engine->baseUrl().resolved(url);
    else
        d->url = url;

    if (url.isEmpty()) {
        QDeclarativeError error;
        error.setDescription(tr("Invalid empty URL"));
        d->state.errors << error;
        return;
    }

    QDeclarativeTypeData *data = QDeclarativeEnginePrivate::get(d->engine)->typeLoader.get(d->url);

    if (data->isCompleteOrError()) {
        d->fromTypeData(data);
        d->progress = 1.0;
    } else {
        d->typeData = data;
        d->typeData->registerCallback(d);
        d->progress = data->progress();
    }

    emit statusChanged(status());
    emit progressChanged(d->progress);
}

QList<QDeclarativeError> QDeclarativeComponent::errors() const
{
    Q_D(const QDeclarativeComponent);
    if (isError())
        return d->state.errors;
    else
        return QList<QDeclarativeError>();
}

QString QDeclarativeComponent::errorString() const
{
    Q_D(const QDeclarativeComponent);
    QString ret;
    if(!isError())
        return ret;
    foreach(const QDeclarativeError &e, d->state.errors) {
        ret += e.url().toString() + QLatin1Char(':') +
               QString::number(e.line()) + QLatin1Char(' ') +
               e.description() + QLatin1Char('\n');
    }
    return ret;
}

QUrl QDeclarativeComponent::url() const
{
    Q_D(const QDeclarativeComponent);
    return d->url;
}

QDeclarativeComponent::QDeclarativeComponent(QDeclarativeComponentPrivate &dd, QObject *parent)
    : QObject(dd, parent)
{
}

QScriptValue QDeclarativeComponent::createObject(QObject* parent)
{
    Q_D(QDeclarativeComponent);
    return d->createObject(parent, QScriptValue(QScriptValue::NullValue));
}

QScriptValue QDeclarativeComponent::createObject(QObject* parent, const QScriptValue& valuemap)
{
    Q_D(QDeclarativeComponent);

    if (!valuemap.isObject() || valuemap.isArray()) {
        qmlInfo(this) << tr("createObject: value is not an object");
        return QScriptValue(QScriptValue::NullValue);
    }
    return d->createObject(parent, valuemap);
}

QScriptValue QDeclarativeComponentPrivate::createObject(QObject *publicParent, const QScriptValue valuemap)
{
    Q_Q(QDeclarativeComponent);
    QDeclarativeContext* ctxt = q->creationContext();
    if(!ctxt && engine)
        ctxt = engine->rootContext();
    if (!ctxt)
        return QScriptValue(QScriptValue::NullValue);
    QObject* ret = q->beginCreate(ctxt);
    if (!ret) {
        q->completeCreate();
        return QScriptValue(QScriptValue::NullValue);
    }

    if (publicParent) {
        ret->setParent(publicParent);
        QList<QDeclarativePrivate::AutoParentFunction> functions = QDeclarativeMetaType::parentFunctions();

        bool needParent = false;

        for (int ii = 0; ii < functions.count(); ++ii) {
            QDeclarativePrivate::AutoParentResult res = functions.at(ii)(ret, publicParent);
            if (res == QDeclarativePrivate::Parented) {
                needParent = false;
                break;
            } else if (res == QDeclarativePrivate::IncompatibleParent) {
                needParent = true;
            }
        }

        if (needParent)
            qWarning("QDeclarativeComponent: Created graphical object was not placed in the graphics scene.");
    }

    QDeclarativeEnginePrivate *priv = QDeclarativeEnginePrivate::get(engine);
    QDeclarativeData::get(ret, true)->setImplicitDestructible();
    QScriptValue newObject = priv->objectClass->newQObject(ret, QMetaType::QObjectStar);

    if (valuemap.isObject() && !valuemap.isArray()) {
        //Iterate through and assign properties
        QScriptValueIterator it(valuemap);
        while (it.hasNext()) {
            it.next();
            QScriptValue prop = newObject;
            QString propName = it.name();
            int index = propName.indexOf(QLatin1Char('.'));
            if (index > 0) {
                QString subProp = propName;
                int lastIndex = 0;
                while (index > 0) {
                    subProp = propName.mid(lastIndex, index - lastIndex);
                    prop = prop.property(subProp);
                    lastIndex = index + 1;
                    index = propName.indexOf(QLatin1Char('.'), index + 1);
                }
                prop.setProperty(propName.mid(propName.lastIndexOf(QLatin1Char('.')) + 1), it.value());
            } else {
                newObject.setProperty(propName, it.value());
            }
        }
    }

    q->completeCreate();

    return newObject;
}

QObject *QDeclarativeComponent::create(QDeclarativeContext *context)
{
    Q_D(QDeclarativeComponent);

    if (!context)
        context = d->engine->rootContext();

    QObject *rv = beginCreate(context);
    completeCreate();
    return rv;
}

QObject *QDeclarativeComponent::beginCreate(QDeclarativeContext *context)
{
    Q_D(QDeclarativeComponent);
    QObject *rv = d->beginCreate(context?QDeclarativeContextData::get(context):0, QBitField());
    if (rv) {
        QDeclarativeData *ddata = QDeclarativeData::get(rv);
        Q_ASSERT(ddata);
        ddata->indestructible = true;
    }
    return rv;
}

QObject *
QDeclarativeComponentPrivate::beginCreate(QDeclarativeContextData *context, const QBitField &bindings)
{
    Q_Q(QDeclarativeComponent);
    if (!context) {
        qWarning("QDeclarativeComponent: Cannot create a component in a null context");
        return 0;
    }

    if (!context->isValid()) {
        qWarning("QDeclarativeComponent: Cannot create a component in an invalid context");
        return 0;
    }

    if (context->engine != engine) {
        qWarning("QDeclarativeComponent: Must create component in context from the same QDeclarativeEngine");
        return 0;
    }

    if (state.completePending) {
        qWarning("QDeclarativeComponent: Cannot create new component instance before completing the previous");
        return 0;
    }

    if (!q->isReady()) {
        qWarning("QDeclarativeComponent: Component is not ready");
        return 0;
    }

    return begin(context, creationContext, cc, start, count, &state, 0, bindings);
}

QObject * QDeclarativeComponentPrivate::begin(QDeclarativeContextData *parentContext,
                                              QDeclarativeContextData *componentCreationContext,
                                              QDeclarativeCompiledData *component, int start, int count,
                                              ConstructionState *state, QList<QDeclarativeError> *errors,
                                              const QBitField &bindings)
{
    QDeclarativeEnginePrivate *enginePriv = QDeclarativeEnginePrivate::get(parentContext->engine);
    bool isRoot = !enginePriv->inBeginCreate;

    Q_ASSERT(!isRoot || state); // Either this isn't a root component, or a state data must be provided
    Q_ASSERT((state != 0) ^ (errors != 0)); // One of state or errors (but not both) must be provided

    if (isRoot) {
        QDeclarativeDebugTrace::startRange(QDeclarativeDebugTrace::Creating);
        QDeclarativeDebugTrace::rangeData(QDeclarativeDebugTrace::Creating, component->url);
    }

    QDeclarativeContextData *ctxt = new QDeclarativeContextData;
    ctxt->isInternal = true;
    ctxt->url = component->url;
    ctxt->imports = component->importCache;

    // Nested global imports
    if (componentCreationContext && start != -1)
        ctxt->importedScripts = componentCreationContext->importedScripts;

    component->importCache->addref();
    ctxt->setParent(parentContext);

    enginePriv->inBeginCreate = true;

    QDeclarativeVME vme;
    QObject *rv = vme.run(ctxt, component, start, count, bindings);

    if (vme.isError()) {
       if(errors) *errors = vme.errors();
       else state->errors = vme.errors();
    }

    if (isRoot) {
        enginePriv->inBeginCreate = false;

        state->bindValues = enginePriv->bindValues;
        state->parserStatus = enginePriv->parserStatus;
        state->finalizedParserStatus = enginePriv->finalizedParserStatus;
        state->componentAttached = enginePriv->componentAttached;
        if (state->componentAttached)
            state->componentAttached->prev = &state->componentAttached;

        enginePriv->componentAttached = 0;
        enginePriv->bindValues.clear();
        enginePriv->parserStatus.clear();
        enginePriv->finalizedParserStatus.clear();
        state->completePending = true;
        enginePriv->inProgressCreations++;
    }

    if (enginePriv->isDebugging && rv) {
        if  (!parentContext->isInternal)
            parentContext->asQDeclarativeContextPrivate()->instances.append(rv);
        QDeclarativeEngineDebugService::instance()->objectCreated(parentContext->engine, rv);
    }

    return rv;
}

void QDeclarativeComponentPrivate::beginDeferred(QDeclarativeEnginePrivate *enginePriv,
                                                 QObject *object, ConstructionState *state)
{
    bool isRoot = !enginePriv->inBeginCreate;
    enginePriv->inBeginCreate = true;

    QDeclarativeVME vme;
    vme.runDeferred(object);

    if (vme.isError())
        state->errors = vme.errors();

    if (isRoot) {
        enginePriv->inBeginCreate = false;

        state->bindValues = enginePriv->bindValues;
        state->parserStatus = enginePriv->parserStatus;
        state->finalizedParserStatus = enginePriv->finalizedParserStatus;
        state->componentAttached = enginePriv->componentAttached;
        if (state->componentAttached)
            state->componentAttached->prev = &state->componentAttached;

        enginePriv->componentAttached = 0;
        enginePriv->bindValues.clear();
        enginePriv->parserStatus.clear();
        enginePriv->finalizedParserStatus.clear();
        state->completePending = true;
        enginePriv->inProgressCreations++;
    }
}

void QDeclarativeComponentPrivate::complete(QDeclarativeEnginePrivate *enginePriv, ConstructionState *state)
{
    if (state->completePending) {
        QT_TRY {
            for (int ii = 0; ii < state->bindValues.count(); ++ii) {
                QDeclarativeEnginePrivate::SimpleList<QDeclarativeAbstractBinding> bv =
                    state->bindValues.at(ii);
                for (int jj = 0; jj < bv.count; ++jj) {
                    if(bv.at(jj)) {
                        // XXX akennedy
                        bv.at(jj)->m_mePtr = 0;
                        bv.at(jj)->setEnabled(true, QDeclarativePropertyPrivate::BypassInterceptor |
                                                    QDeclarativePropertyPrivate::DontRemoveBinding);
                    }
                }
                QDeclarativeEnginePrivate::clear(bv);
            }

            for (int ii = 0; ii < state->parserStatus.count(); ++ii) {
                QDeclarativeEnginePrivate::SimpleList<QDeclarativeParserStatus> ps =
                    state->parserStatus.at(ii);

                for (int jj = ps.count - 1; jj >= 0; --jj) {
                    QDeclarativeParserStatus *status = ps.at(jj);
                    if (status && status->d) {
                        status->d = 0;
                        status->componentComplete();
                    }
                }
                QDeclarativeEnginePrivate::clear(ps);
            }

            for (int ii = 0; ii < state->finalizedParserStatus.count(); ++ii) {
                QPair<QDeclarativeGuard<QObject>, int> status = state->finalizedParserStatus.at(ii);
                QObject *obj = status.first;
                if (obj) {
                    void *args[] = { 0 };
                    QMetaObject::metacall(obj, QMetaObject::InvokeMetaMethod,
                                          status.second, args);
                }
            }

            //componentComplete() can register additional finalization objects
            //that are then never handled. Handle them manually here.
            if (1 == enginePriv->inProgressCreations) {
                for (int ii = 0; ii < enginePriv->finalizedParserStatus.count(); ++ii) {
                    QPair<QDeclarativeGuard<QObject>, int> status = enginePriv->finalizedParserStatus.at(ii);
                    QObject *obj = status.first;
                    if (obj) {
                        void *args[] = { 0 };
                        QMetaObject::metacall(obj, QMetaObject::InvokeMetaMethod,
                                              status.second, args);
                    }
                }
                enginePriv->finalizedParserStatus.clear();
            }

            while (state->componentAttached) {
                QDeclarativeComponentAttached *a = state->componentAttached;
                a->rem();
                QDeclarativeData *d = QDeclarativeData::get(a->parent());
                Q_ASSERT(d);
                Q_ASSERT(d->context);
                a->add(&d->context->componentAttached);
                emit a->completed();
            }
        } QT_CATCH(const std::exception&) {
            state->bindValues.clear();
            state->parserStatus.clear();
            state->finalizedParserStatus.clear();
            state->completePending = false;
            enginePriv->inProgressCreations--;
            QT_RETHROW;
        }

        state->bindValues.clear();
        state->parserStatus.clear();
        state->finalizedParserStatus.clear();
        state->completePending = false;

        enginePriv->inProgressCreations--;
        if (0 == enginePriv->inProgressCreations) {
            while (enginePriv->erroredBindings) {
                enginePriv->warning(enginePriv->erroredBindings->error);
                enginePriv->erroredBindings->removeError();
            }
        }
    }
}

void QDeclarativeComponent::completeCreate()
{
    Q_D(QDeclarativeComponent);
    d->completeCreate();
}

void QDeclarativeComponentPrivate::completeCreate()
{
    if (state.completePending) {
        QDeclarativeEnginePrivate *ep = QDeclarativeEnginePrivate::get(engine);
        complete(ep, &state);

        QDeclarativeDebugTrace::endRange(QDeclarativeDebugTrace::Creating);
    }
}

QDeclarativeComponentAttached::QDeclarativeComponentAttached(QObject *parent)
: QObject(parent), prev(0), next(0)
{
}

QDeclarativeComponentAttached::~QDeclarativeComponentAttached()
{
    if (prev) *prev = next;
    if (next) next->prev = prev;
    prev = 0;
    next = 0;
}

QDeclarativeComponentAttached *QDeclarativeComponent::qmlAttachedProperties(QObject *obj)
{
    QDeclarativeComponentAttached *a = new QDeclarativeComponentAttached(obj);

    QDeclarativeEngine *engine = qmlEngine(obj);
    if (!engine)
        return a;

    if (QDeclarativeEnginePrivate::get(engine)->inBeginCreate) {
        QDeclarativeEnginePrivate *p = QDeclarativeEnginePrivate::get(engine);
        a->add(&p->componentAttached);
    } else {
        QDeclarativeData *d = QDeclarativeData::get(obj);
        Q_ASSERT(d);
        Q_ASSERT(d->context);
        a->add(&d->context->componentAttached);
    }

    return a;
}

QT_END_NAMESPACE