qdeclarativeloader.cpp

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#include "private/qdeclarativeloader_p_p.h"

#include <qdeclarativeinfo.h>
#include <qdeclarativeengine_p.h>
#include <qdeclarativeglobal_p.h>

QT_BEGIN_NAMESPACE

QDeclarativeLoaderPrivate::QDeclarativeLoaderPrivate()
    : item(0), component(0), ownComponent(false), updatingSize(false),
      itemWidthValid(false), itemHeightValid(false)
{
}

QDeclarativeLoaderPrivate::~QDeclarativeLoaderPrivate()
{
}

void QDeclarativeLoaderPrivate::itemGeometryChanged(QDeclarativeItem *resizeItem, const QRectF &newGeometry, const QRectF &oldGeometry)
{
    if (resizeItem == item) {
        if (!updatingSize && newGeometry.width() != oldGeometry.width())
            itemWidthValid = true;
        if (!updatingSize && newGeometry.height() != oldGeometry.height())
            itemHeightValid = true;
        _q_updateSize(false);
    }
    QDeclarativeItemChangeListener::itemGeometryChanged(resizeItem, newGeometry, oldGeometry);
}

void QDeclarativeLoaderPrivate::clear()
{
    if (ownComponent) {
        component->deleteLater();
        component = 0;
        ownComponent = false;
    }
    source = QUrl();

    if (item) {
        if (QDeclarativeItem *qmlItem = qobject_cast<QDeclarativeItem*>(item)) {
            QDeclarativeItemPrivate *p =
                    static_cast<QDeclarativeItemPrivate *>(QGraphicsItemPrivate::get(qmlItem));
            p->removeItemChangeListener(this, QDeclarativeItemPrivate::Geometry);
        }

        // We can't delete immediately because our item may have triggered
        // the Loader to load a different item.
        if (item->scene()) {
            item->scene()->removeItem(item);
        } else {
            item->setParentItem(0);
            item->setVisible(false);
        }
        item->deleteLater();
        item = 0;
    }
}

void QDeclarativeLoaderPrivate::initResize()
{
    Q_Q(QDeclarativeLoader);
    if (QDeclarativeItem *qmlItem = qobject_cast<QDeclarativeItem*>(item)) {
        QDeclarativeItemPrivate *p =
                static_cast<QDeclarativeItemPrivate *>(QGraphicsItemPrivate::get(qmlItem));
        p->addItemChangeListener(this, QDeclarativeItemPrivate::Geometry);
        // We may override the item's size, so we need to remember
        // whether the item provided its own valid size.
        itemWidthValid = p->widthValid;
        itemHeightValid = p->heightValid;
    } else if (item && item->isWidget()) {
        QGraphicsWidget *widget = static_cast<QGraphicsWidget*>(item);
        widget->installEventFilter(q);
    }
    _q_updateSize();
}

QDeclarativeLoader::QDeclarativeLoader(QDeclarativeItem *parent)
  : QDeclarativeImplicitSizeItem(*(new QDeclarativeLoaderPrivate), parent)
{
    Q_D(QDeclarativeLoader);
    d->flags |= QGraphicsItem::ItemIsFocusScope;
}

QDeclarativeLoader::~QDeclarativeLoader()
{
    Q_D(QDeclarativeLoader);
    if (d->item) {
        if (QDeclarativeItem *qmlItem = qobject_cast<QDeclarativeItem*>(d->item)) {
            QDeclarativeItemPrivate *p =
                    static_cast<QDeclarativeItemPrivate *>(QGraphicsItemPrivate::get(qmlItem));
            p->removeItemChangeListener(d, QDeclarativeItemPrivate::Geometry);
        }
    }
}

QUrl QDeclarativeLoader::source() const
{
    Q_D(const QDeclarativeLoader);
    return d->source;
}

void QDeclarativeLoader::setSource(const QUrl &url)
{
    Q_D(QDeclarativeLoader);
    if (d->source == url)
        return;

    d->clear();

    d->source = url;

    if (d->source.isEmpty()) {
        emit sourceChanged();
        emit statusChanged();
        emit progressChanged();
        emit itemChanged();
        return;
    }

    d->component = new QDeclarativeComponent(qmlEngine(this), d->source, this);
    d->ownComponent = true;

    if (isComponentComplete())
        d->load();
}

QDeclarativeComponent *QDeclarativeLoader::sourceComponent() const
{
    Q_D(const QDeclarativeLoader);
    return d->component;
}

void QDeclarativeLoader::setSourceComponent(QDeclarativeComponent *comp)
{
    Q_D(QDeclarativeLoader);
    if (comp == d->component)
        return;

    d->clear();

    d->component = comp;
    d->ownComponent = false;

    if (!d->component) {
        emit sourceChanged();
        emit statusChanged();
        emit progressChanged();
        emit itemChanged();
        return;
    }

    if (isComponentComplete())
        d->load();
}

void QDeclarativeLoader::resetSourceComponent()
{
    setSourceComponent(0);
}

void QDeclarativeLoaderPrivate::load()
{
    Q_Q(QDeclarativeLoader);

    if (!q->isComponentComplete() || !component)
        return;

    if (!component->isLoading()) {
        _q_sourceLoaded();
    } else {
        QObject::connect(component, SIGNAL(statusChanged(QDeclarativeComponent::Status)),
                q, SLOT(_q_sourceLoaded()));
        QObject::connect(component, SIGNAL(progressChanged(qreal)),
                q, SIGNAL(progressChanged()));
        emit q->statusChanged();
        emit q->progressChanged();
        emit q->sourceChanged();
        emit q->itemChanged();
    }
}

void QDeclarativeLoaderPrivate::_q_sourceLoaded()
{
    Q_Q(QDeclarativeLoader);

    if (component) {
        if (!component->errors().isEmpty()) {
            QDeclarativeEnginePrivate::warning(qmlEngine(q), component->errors());
            emit q->sourceChanged();
            emit q->statusChanged();
            emit q->progressChanged();
            return;
        }

        QDeclarativeContext *creationContext = component->creationContext();
        if (!creationContext) creationContext = qmlContext(q);
        QDeclarativeContext *ctxt = new QDeclarativeContext(creationContext);
        ctxt->setContextObject(q);

        QDeclarativeGuard<QDeclarativeComponent> c = component;
        QObject *obj = component->beginCreate(ctxt);
        if (component != c) {
            // component->create could trigger a change in source that causes
            // component to be set to something else. In that case we just
            // need to cleanup.
            if (c)
                c->completeCreate();
            delete obj;
            delete ctxt;
            return;
        }
        if (obj) {
            item = qobject_cast<QGraphicsObject *>(obj);
            if (item) {
                QDeclarative_setParent_noEvent(ctxt, obj);
                QDeclarative_setParent_noEvent(item, q);
                item->setParentItem(q);
//                item->setFocus(true);
                initResize();
            } else {
                qmlInfo(q) << QDeclarativeLoader::tr("Loader does not support loading non-visual elements.");
                delete obj;
                delete ctxt;
            }
        } else {
            if (!component->errors().isEmpty())
                QDeclarativeEnginePrivate::warning(qmlEngine(q), component->errors());
            delete obj;
            delete ctxt;
            source = QUrl();
        }
        component->completeCreate();
        emit q->sourceChanged();
        emit q->statusChanged();
        emit q->progressChanged();
        emit q->itemChanged();
        emit q->loaded();
    }
}

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

    if (d->component)
        return static_cast<QDeclarativeLoader::Status>(d->component->status());

    if (d->item)
        return Ready;

    return d->source.isEmpty() ? Null : Error;
}

void QDeclarativeLoader::componentComplete()
{
    Q_D(QDeclarativeLoader);

    QDeclarativeItem::componentComplete();
    d->load();
}


qreal QDeclarativeLoader::progress() const
{
    Q_D(const QDeclarativeLoader);

    if (d->item)
        return 1.0;

    if (d->component)
        return d->component->progress();

    return 0.0;
}

void QDeclarativeLoaderPrivate::_q_updateSize(bool loaderGeometryChanged)
{
    Q_Q(QDeclarativeLoader);
    if (!item || updatingSize)
        return;

    updatingSize = true;
    if (QDeclarativeItem *qmlItem = qobject_cast<QDeclarativeItem*>(item)) {
        if (!itemWidthValid)
            q->setImplicitWidth(qmlItem->implicitWidth());
        else
            q->setImplicitWidth(qmlItem->width());
        if (loaderGeometryChanged && q->widthValid())
            qmlItem->setWidth(q->width());
        if (!itemHeightValid)
            q->setImplicitHeight(qmlItem->implicitHeight());
        else
            q->setImplicitHeight(qmlItem->height());
        if (loaderGeometryChanged && q->heightValid())
            qmlItem->setHeight(q->height());
    } else if (item && item->isWidget()) {
        QGraphicsWidget *widget = static_cast<QGraphicsWidget*>(item);
        QSizeF widgetSize = widget->size();
        q->setImplicitWidth(widgetSize.width());
        if (loaderGeometryChanged && q->widthValid())
            widgetSize.setWidth(q->width());
        q->setImplicitHeight(widgetSize.height());
        if (loaderGeometryChanged && q->heightValid())
            widgetSize.setHeight(q->height());
        if (widget->size() != widgetSize)
            widget->resize(widgetSize);
    }
    updatingSize = false;
}

QGraphicsObject *QDeclarativeLoader::item() const
{
    Q_D(const QDeclarativeLoader);
    return d->item;
}

void QDeclarativeLoader::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)
{
    Q_D(QDeclarativeLoader);
    if (newGeometry != oldGeometry) {
        d->_q_updateSize();
    }
    QDeclarativeItem::geometryChanged(newGeometry, oldGeometry);
}

QVariant QDeclarativeLoader::itemChange(GraphicsItemChange change, const QVariant &value)
{
    Q_D(QDeclarativeLoader);
    if (change == ItemSceneHasChanged) {
        if (d->item && d->item->isWidget()) {
            d->item->removeEventFilter(this);
            d->item->installEventFilter(this);
        }
    }
    return QDeclarativeItem::itemChange(change, value);
}

bool QDeclarativeLoader::eventFilter(QObject *watched, QEvent *e)
{
    Q_D(QDeclarativeLoader);
    if (watched == d->item && e->type() == QEvent::GraphicsSceneResize) {
        if (d->item && d->item->isWidget())
            d->_q_updateSize(false);
    }
    return QDeclarativeItem::eventFilter(watched, e);
}

#include <moc_qdeclarativeloader_p.cpp>

QT_END_NAMESPACE