qdeclarativeview.cpp

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#include "qdeclarativeview.h"

#include <qdeclarative.h>
#include <qdeclarativeitem.h>
#include <qdeclarativeengine.h>
#include <qdeclarativecontext.h>
#include <qdeclarativeglobal_p.h>
#include <qdeclarativeguard_p.h>

#include <private/qdeclarativedebugtrace_p.h>
#include <private/qdeclarativeinspectorservice_p.h>

#include <qscriptvalueiterator.h>
#include <qdebug.h>
#include <qtimer.h>
#include <qevent.h>
#include <qdir.h>
#include <qcoreapplication.h>
#include <qfontdatabase.h>
#include <qicon.h>
#include <qurl.h>
#include <qlayout.h>
#include <qwidget.h>
#include <qgraphicswidget.h>
#include <qbasictimer.h>
#include <QtCore/qabstractanimation.h>
#include <private/qgraphicsview_p.h>
#include <private/qdeclarativeitem_p.h>
#include <private/qabstractanimation_p.h>
#include <private/qdeclarativeitemchangelistener_p.h>

QT_BEGIN_NAMESPACE

DEFINE_BOOL_CONFIG_OPTION(frameRateDebug, QML_SHOW_FRAMERATE)

class QDeclarativeScene : public QGraphicsScene
{
public:
    QDeclarativeScene(QObject *parent = 0);

protected:
    virtual void keyPressEvent(QKeyEvent *);
    virtual void keyReleaseEvent(QKeyEvent *);

    virtual void mouseMoveEvent(QGraphicsSceneMouseEvent *);
    virtual void mousePressEvent(QGraphicsSceneMouseEvent *);
    virtual void mouseReleaseEvent(QGraphicsSceneMouseEvent *);
};

QDeclarativeScene::QDeclarativeScene(QObject *parent) : QGraphicsScene(parent)
{
}

void QDeclarativeScene::keyPressEvent(QKeyEvent *e)
{
    QDeclarativeDebugTrace::addEvent(QDeclarativeDebugTrace::Key);

    QGraphicsScene::keyPressEvent(e);
}

void QDeclarativeScene::keyReleaseEvent(QKeyEvent *e)
{
    QDeclarativeDebugTrace::addEvent(QDeclarativeDebugTrace::Key);

    QGraphicsScene::keyReleaseEvent(e);
}

void QDeclarativeScene::mouseMoveEvent(QGraphicsSceneMouseEvent *e)
{
    QDeclarativeDebugTrace::addEvent(QDeclarativeDebugTrace::Mouse);

    QGraphicsScene::mouseMoveEvent(e);
}

void QDeclarativeScene::mousePressEvent(QGraphicsSceneMouseEvent *e)
{
    QDeclarativeDebugTrace::addEvent(QDeclarativeDebugTrace::Mouse);

    QGraphicsScene::mousePressEvent(e);
}

void QDeclarativeScene::mouseReleaseEvent(QGraphicsSceneMouseEvent *e)
{
    QDeclarativeDebugTrace::addEvent(QDeclarativeDebugTrace::Mouse);

    QGraphicsScene::mouseReleaseEvent(e);
}

class QDeclarativeViewPrivate : public QGraphicsViewPrivate, public QDeclarativeItemChangeListener
{
    Q_DECLARE_PUBLIC(QDeclarativeView)
public:
    QDeclarativeViewPrivate()
        : root(0), declarativeItemRoot(0), graphicsWidgetRoot(0), component(0),
          resizeMode(QDeclarativeView::SizeViewToRootObject), initialSize(0,0) {}
    ~QDeclarativeViewPrivate() { delete root; delete engine; }
    void execute();
    void itemGeometryChanged(QDeclarativeItem *item, const QRectF &newGeometry, const QRectF &oldGeometry);
    void initResize();
    void updateSize();
    inline QSize rootObjectSize() const;

    QDeclarativeGuard<QGraphicsObject> root;
    QDeclarativeGuard<QDeclarativeItem> declarativeItemRoot;
    QDeclarativeGuard<QGraphicsWidget> graphicsWidgetRoot;

    QUrl source;

    QDeclarativeEngine* engine;
    QDeclarativeComponent *component;
    QBasicTimer resizetimer;

    QDeclarativeView::ResizeMode resizeMode;
    QSize initialSize;
    QElapsedTimer frameTimer;

    void init();
};

void QDeclarativeViewPrivate::execute()
{
    Q_Q(QDeclarativeView);
    if (root) {
        delete root;
        root = 0;
    }
    if (component) {
        delete component;
        component = 0;
    }
    if (!source.isEmpty()) {
        component = new QDeclarativeComponent(engine, source, q);
        if (!component->isLoading()) {
            q->continueExecute();
        } else {
            QObject::connect(component, SIGNAL(statusChanged(QDeclarativeComponent::Status)), q, SLOT(continueExecute()));
        }
    }
}

void QDeclarativeViewPrivate::itemGeometryChanged(QDeclarativeItem *resizeItem, const QRectF &newGeometry, const QRectF &oldGeometry)
{
    Q_Q(QDeclarativeView);
    if (resizeItem == root && resizeMode == QDeclarativeView::SizeViewToRootObject) {
        // wait for both width and height to be changed
        resizetimer.start(0,q);
    }
    QDeclarativeItemChangeListener::itemGeometryChanged(resizeItem, newGeometry, oldGeometry);
}

QDeclarativeView::QDeclarativeView(QWidget *parent)
    : QGraphicsView(*(new QDeclarativeViewPrivate), parent)
{
    Q_D(QDeclarativeView);
    setSizePolicy(QSizePolicy::Preferred,QSizePolicy::Preferred);
    d->init();
}

QDeclarativeView::QDeclarativeView(const QUrl &source, QWidget *parent)
    : QGraphicsView(*(new QDeclarativeViewPrivate), parent)
{
    Q_D(QDeclarativeView);
    setSizePolicy(QSizePolicy::Preferred,QSizePolicy::Preferred);
    d->init();
    setSource(source);
}

void QDeclarativeViewPrivate::init()
{
    Q_Q(QDeclarativeView);
    engine = new QDeclarativeEngine();
    q->setScene(new QDeclarativeScene(q));

    q->setOptimizationFlags(QGraphicsView::DontSavePainterState);
    q->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    q->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    q->setFrameStyle(0);

    // These seem to give the best performance
    q->setViewportUpdateMode(QGraphicsView::BoundingRectViewportUpdate);
    q->scene()->setItemIndexMethod(QGraphicsScene::NoIndex);
    q->viewport()->setFocusPolicy(Qt::NoFocus);
    q->setFocusPolicy(Qt::StrongFocus);

    q->scene()->setStickyFocus(true);  //### needed for correct focus handling

#ifdef QDECLARATIVEVIEW_NOBACKGROUND
    q->setAttribute(Qt::WA_OpaquePaintEvent);
    q->setAttribute(Qt::WA_NoSystemBackground);
    q->viewport()->setAttribute(Qt::WA_OpaquePaintEvent);
    q->viewport()->setAttribute(Qt::WA_NoSystemBackground);
#endif

    QDeclarativeInspectorService::instance()->addView(q);
}

QDeclarativeView::~QDeclarativeView()
{
    QDeclarativeInspectorService::instance()->removeView(this);
}

void QDeclarativeView::setSource(const QUrl& url)
{
    Q_D(QDeclarativeView);
    d->source = url;
    d->execute();
}

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

QDeclarativeEngine* QDeclarativeView::engine() const
{
    Q_D(const QDeclarativeView);
    return d->engine;
}

QDeclarativeContext* QDeclarativeView::rootContext() const
{
    Q_D(const QDeclarativeView);
    return d->engine->rootContext();
}

QDeclarativeView::Status QDeclarativeView::status() const
{
    Q_D(const QDeclarativeView);
    if (!d->component)
        return QDeclarativeView::Null;

    return QDeclarativeView::Status(d->component->status());
}

QList<QDeclarativeError> QDeclarativeView::errors() const
{
    Q_D(const QDeclarativeView);
    if (d->component)
        return d->component->errors();
    return QList<QDeclarativeError>();
}

void QDeclarativeView::setResizeMode(ResizeMode mode)
{
    Q_D(QDeclarativeView);
    if (d->resizeMode == mode)
        return;

    if (d->declarativeItemRoot) {
        if (d->resizeMode == SizeViewToRootObject) {
            QDeclarativeItemPrivate *p =
                static_cast<QDeclarativeItemPrivate *>(QGraphicsItemPrivate::get(d->declarativeItemRoot));
            p->removeItemChangeListener(d, QDeclarativeItemPrivate::Geometry);
        }
    } else if (d->graphicsWidgetRoot) {
         if (d->resizeMode == QDeclarativeView::SizeViewToRootObject) {
             d->graphicsWidgetRoot->removeEventFilter(this);
         }
    }

    d->resizeMode = mode;
    if (d->root) {
        d->initResize();
    }
}

void QDeclarativeViewPrivate::initResize()
{
    Q_Q(QDeclarativeView);
    if (declarativeItemRoot) {
        if (resizeMode == QDeclarativeView::SizeViewToRootObject) {
            QDeclarativeItemPrivate *p =
                static_cast<QDeclarativeItemPrivate *>(QGraphicsItemPrivate::get(declarativeItemRoot));
            p->addItemChangeListener(this, QDeclarativeItemPrivate::Geometry);
        }
    } else if (graphicsWidgetRoot) {
        if (resizeMode == QDeclarativeView::SizeViewToRootObject) {
            graphicsWidgetRoot->installEventFilter(q);
        }
    }
    updateSize();
}

void QDeclarativeViewPrivate::updateSize()
{
    Q_Q(QDeclarativeView);
    if (!root)
        return;
    if (declarativeItemRoot) {
        if (resizeMode == QDeclarativeView::SizeViewToRootObject) {
            QSize newSize = QSize(declarativeItemRoot->width(), declarativeItemRoot->height());
            if (newSize.isValid() && newSize != q->size()) {
                q->resize(newSize);
            }
        } else if (resizeMode == QDeclarativeView::SizeRootObjectToView) {
            if (!qFuzzyCompare(q->width(), declarativeItemRoot->width()))
                declarativeItemRoot->setWidth(q->width());
            if (!qFuzzyCompare(q->height(), declarativeItemRoot->height()))
                declarativeItemRoot->setHeight(q->height());
        }
    } else if (graphicsWidgetRoot) {
        if (resizeMode == QDeclarativeView::SizeViewToRootObject) {
            QSize newSize = QSize(graphicsWidgetRoot->size().width(), graphicsWidgetRoot->size().height());
            if (newSize.isValid() && newSize != q->size()) {
                q->resize(newSize);
            }
        } else if (resizeMode == QDeclarativeView::SizeRootObjectToView) {
            QSizeF newSize = QSize(q->size().width(), q->size().height());
            if (newSize.isValid() && newSize != graphicsWidgetRoot->size()) {
                graphicsWidgetRoot->resize(newSize);
            }
        }
    }
    q->updateGeometry();
}

QSize QDeclarativeViewPrivate::rootObjectSize() const
{
    QSize rootObjectSize(0,0);
    int widthCandidate = -1;
    int heightCandidate = -1;
    if (root) {
        QSizeF size = root->boundingRect().size();
        widthCandidate = size.width();
        heightCandidate = size.height();
    }
    if (widthCandidate > 0) {
        rootObjectSize.setWidth(widthCandidate);
    }
    if (heightCandidate > 0) {
        rootObjectSize.setHeight(heightCandidate);
    }
    return rootObjectSize;
}

QDeclarativeView::ResizeMode QDeclarativeView::resizeMode() const
{
    Q_D(const QDeclarativeView);
    return d->resizeMode;
}

void QDeclarativeView::continueExecute()
{
    Q_D(QDeclarativeView);
    disconnect(d->component, SIGNAL(statusChanged(QDeclarativeComponent::Status)), this, SLOT(continueExecute()));

    if (d->component->isError()) {
        QList<QDeclarativeError> errorList = d->component->errors();
        foreach (const QDeclarativeError &error, errorList) {
            qWarning() << error;
        }
        emit statusChanged(status());
        return;
    }

    QObject *obj = d->component->create();

    if(d->component->isError()) {
        QList<QDeclarativeError> errorList = d->component->errors();
        foreach (const QDeclarativeError &error, errorList) {
            qWarning() << error;
        }
        emit statusChanged(status());
        return;
    }

    setRootObject(obj);
    emit statusChanged(status());
}

void QDeclarativeView::setRootObject(QObject *obj)
{
    Q_D(QDeclarativeView);
    if (d->root == obj || !scene())
        return;
    if (QDeclarativeItem *declarativeItem = qobject_cast<QDeclarativeItem *>(obj)) {
        scene()->addItem(declarativeItem);
        d->root = declarativeItem;
        d->declarativeItemRoot = declarativeItem;
    } else if (QGraphicsObject *graphicsObject = qobject_cast<QGraphicsObject *>(obj)) {
        scene()->addItem(graphicsObject);
        d->root = graphicsObject;
        if (graphicsObject->isWidget()) {
            d->graphicsWidgetRoot = static_cast<QGraphicsWidget*>(graphicsObject);
        } else {
            qWarning() << "QDeclarativeView::resizeMode is not honored for components of type QGraphicsObject";
        }
    } else if (obj) {
        qWarning() << "QDeclarativeView only supports loading of root objects that derive from QGraphicsObject";
        if (QWidget* widget  = qobject_cast<QWidget *>(obj)) {
            window()->setAttribute(Qt::WA_OpaquePaintEvent, false);
            window()->setAttribute(Qt::WA_NoSystemBackground, false);
            if (layout() && layout()->count()) {
                // Hide the QGraphicsView in GV mode.
                QLayoutItem *item = layout()->itemAt(0);
                if (item->widget())
                    item->widget()->hide();
            }
            widget->setParent(this);
            if (isVisible()) {
                widget->setVisible(true);
            }
            resize(widget->size());
        }
    }

    if (d->root) {
        d->initialSize = d->rootObjectSize();
        if (d->initialSize != size()) {
            if (!(parentWidget() && parentWidget()->layout())) {
                resize(d->initialSize);
            }
        }
        d->initResize();
    }
}

void QDeclarativeView::timerEvent(QTimerEvent* e)
{
    Q_D(QDeclarativeView);
    if (!e || e->timerId() == d->resizetimer.timerId()) {
        d->updateSize();
        d->resizetimer.stop();
    }
}

bool QDeclarativeView::eventFilter(QObject *watched, QEvent *e)
{
    Q_D(QDeclarativeView);
    if (watched == d->root && d->resizeMode == SizeViewToRootObject) {
        if (d->graphicsWidgetRoot) {
            if (e->type() == QEvent::GraphicsSceneResize) {
                d->updateSize();
            }
        }
    }
    return QGraphicsView::eventFilter(watched, e);
}

QSize QDeclarativeView::sizeHint() const
{
    Q_D(const QDeclarativeView);
    QSize rootObjectSize = d->rootObjectSize();
    if (rootObjectSize.isEmpty()) {
        return size();
    } else {
        return rootObjectSize;
    }
}

QSize QDeclarativeView::initialSize() const
{
    Q_D(const QDeclarativeView);
    return d->initialSize;
}

QGraphicsObject *QDeclarativeView::rootObject() const
{
    Q_D(const QDeclarativeView);
    return d->root;
}

void QDeclarativeView::resizeEvent(QResizeEvent *e)
{
    Q_D(QDeclarativeView);
    if (d->resizeMode == SizeRootObjectToView) {
        d->updateSize();
    }
    if (d->declarativeItemRoot) {
        setSceneRect(QRectF(0, 0, d->declarativeItemRoot->width(), d->declarativeItemRoot->height()));
    } else if (d->root) {
        setSceneRect(d->root->boundingRect());
    } else {
        setSceneRect(rect());
    }
    emit sceneResized(e->size());
    QGraphicsView::resizeEvent(e);
}

void QDeclarativeView::paintEvent(QPaintEvent *event)
{
    Q_D(QDeclarativeView);

    QDeclarativeDebugTrace::addEvent(QDeclarativeDebugTrace::FramePaint);
    QDeclarativeDebugTrace::startRange(QDeclarativeDebugTrace::Painting);

    int time = 0;
    if (frameRateDebug())
        time = d->frameTimer.restart();

    QGraphicsView::paintEvent(event);

    QDeclarativeDebugTrace::endRange(QDeclarativeDebugTrace::Painting);

    if (frameRateDebug())
        qDebug() << "paintEvent:" << d->frameTimer.elapsed() << "time since last frame:" << time;

#if QT_SHOW_DECLARATIVEVIEW_FPS
    static QTime timer;
    static int frames;

    if (frames == 0) {
        timer.start();
    } else if (timer.elapsed() > 5000) {
        qreal avgtime = timer.elapsed() / (qreal) frames;
        qDebug("Average time per frame: %f ms (%i fps)", avgtime, int(1000 / avgtime));
        timer.start();
        frames = 0;
    }
    ++frames;
    scene()->update();
#endif

}

QT_END_NAMESPACE