path: root/src/quick/items/qquickview.cpp

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#include "qquickview.h"
#include "qquickview_p.h"

#include "qquickcanvas_p.h"
#include "qquickitem_p.h"
#include "qquickitemchangelistener_p.h"

#include <private/qqmlprofilerservice_p.h>
#include <private/qqmlinspectorservice_p.h>

#include <QtQml/qqmlengine.h>
#include <private/qqmlengine_p.h>
#include <QtCore/qbasictimer.h>


QT_BEGIN_NAMESPACE

void QQuickViewPrivate::init()
{
    Q_Q(QQuickView);

    engine.setIncubationController(q->incubationController());

    if (QQmlDebugService::isDebuggingEnabled())
        QQmlInspectorService::instance()->addView(q);
}

QQuickViewPrivate::QQuickViewPrivate()
    : root(0), component(0), resizeMode(QQuickView::SizeViewToRootObject), initialSize(0,0)
{
}

QQuickViewPrivate::~QQuickViewPrivate()
{
    if (QQmlDebugService::isDebuggingEnabled())
        QQmlInspectorService::instance()->removeView(q_func());

    delete root;
}

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

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

/*!
    \class QQuickView
    \since QtQuick 2.0
    \brief The QQuickView class provides a window for displaying a Qt Quick user interface.

    \inmodule QtQuick

    This is a convenience subclass of QQuickCanvas which
    will automatically load and display a QML scene when given the URL of the main source file. Alternatively,
    you can instantiate your own objects using QQmlComponent and place them in a manually setup QQuickCanvas.

    Typical usage:

    \code
    QQuickView *view = new QQuickView;
    view->setSource(QUrl::fromLocalFile("myqmlfile.qml"));
    view->show();
    \endcode

    To receive errors related to loading and executing QML with QQuickView,
    you can connect to the statusChanged() signal and monitor for QQuickView::Error.
    The errors are available via QQuickView::errors().

    \sa {Using QML Bindings in C++ Applications}
*/


/*! \fn void QQuickView::sceneResized(QSize size)
  This signal is emitted when the view is resized to \a size.
*/

/*! \fn void QQuickView::statusChanged(QQuickView::Status status)
    This signal is emitted when the component's current \a status changes.
*/

/*! \fn void QQuickView::initialSizeChanged(QSize size)
  \internal
*/

/*!
  \fn QQuickView::QQuickView(QWindow *parent)

  Constructs a QQuickView with the given \a parent.
*/
QQuickView::QQuickView(QWindow *parent, Qt::WindowFlags f)
: QQuickCanvas(*(new QQuickViewPrivate), parent)
{
    setWindowFlags(f);
    d_func()->init();
}

/*!
  \fn QQuickView::QQuickView(const QUrl &source, QWidget *parent)

  Constructs a QQuickView with the given QML \a source and \a parent.
*/
QQuickView::QQuickView(const QUrl &source, QWindow *parent, Qt::WindowFlags f)
: QQuickCanvas(*(new QQuickViewPrivate), parent)
{
    setWindowFlags(f);
    d_func()->init();
    setSource(source);
}

QQuickView::~QQuickView()
{
}

/*! \property QQuickView::source
  \brief The URL of the source of the QML component.

  Changing this property causes the QML component to be reloaded.

    Ensure that the URL provided is full and correct, in particular, use
    \l QUrl::fromLocalFile() when loading a file from the local filesystem.
 */

/*!
    Sets the source to the \a url, loads the QML component and instantiates it.

    Ensure that the URL provided is full and correct, in particular, use
    \l QUrl::fromLocalFile() when loading a file from the local filesystem.

    Calling this methods multiple times with the same url will result
    in the QML being reloaded.
 */
void QQuickView::setSource(const QUrl& url)
{
    Q_D(QQuickView);
    d->source = url;
    d->execute();
}

/*!
  Returns the source URL, if set.

  \sa setSource()
 */
QUrl QQuickView::source() const
{
    Q_D(const QQuickView);
    return d->source;
}

/*!
  Returns a pointer to the QQmlEngine used for instantiating
  QML Components.
 */
QQmlEngine* QQuickView::engine() const
{
    Q_D(const QQuickView);
    return const_cast<QQmlEngine *>(&d->engine);
}

/*!
  This function returns the root of the context hierarchy.  Each QML
  component is instantiated in a QQmlContext.  QQmlContext's are
  essential for passing data to QML components.  In QML, contexts are
  arranged hierarchically and this hierarchy is managed by the
  QQmlEngine.
 */
QQmlContext* QQuickView::rootContext() const
{
    Q_D(const QQuickView);
    return d->engine.rootContext();
}

/*!
    \enum QQuickView::Status
    Specifies the loading status of the QQuickView.

    \value Null This QQuickView has no source set.
    \value Ready This QQuickView has loaded and created the QML component.
    \value Loading This QQuickView is loading network data.
    \value Error One or more errors has occurred. Call errors() to retrieve a list
           of errors.
*/

/*! \enum QQuickView::ResizeMode

  This enum specifies how to resize the view.

  \value SizeViewToRootObject The view resizes with the root item in the QML.
  \value SizeRootObjectToView The view will automatically resize the root item to the size of the view.
*/

/*!
    \property QQuickView::status
    The component's current \l{QQuickView::Status} {status}.
*/

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

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

/*!
    Return the list of errors that occurred during the last compile or create
    operation.  When the status is not Error, an empty list is returned.
*/
QList<QQmlError> QQuickView::errors() const
{
    Q_D(const QQuickView);
    if (d->component)
        return d->component->errors();
    return QList<QQmlError>();
}

/*!
    \property QQuickView::resizeMode
    \brief whether the view should resize the canvas contents

    If this property is set to SizeViewToRootObject (the default), the view
    resizes with the root item in the QML.

    If this property is set to SizeRootObjectToView, the view will
    automatically resize the root item.

    Regardless of this property, the sizeHint of the view
    is the initial size of the root item. Note though that
    since QML may load dynamically, that size may change.
*/

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

    if (d->root) {
        if (d->resizeMode == SizeViewToRootObject) {
            QQuickItemPrivate *p = QQuickItemPrivate::get(d->root);
            p->removeItemChangeListener(d, QQuickItemPrivate::Geometry);
        }
    }

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

void QQuickViewPrivate::initResize()
{
    if (root) {
        if (resizeMode == QQuickView::SizeViewToRootObject) {
            QQuickItemPrivate *p = QQuickItemPrivate::get(root);
            p->addItemChangeListener(this, QQuickItemPrivate::Geometry);
        }
    }
    updateSize();
}

void QQuickViewPrivate::updateSize()
{
    Q_Q(QQuickView);
    if (!root)
        return;

    if (resizeMode == QQuickView::SizeViewToRootObject) {
        QSize newSize = QSize(root->width(), root->height());
        if (newSize.isValid() && newSize != q->size()) {
            q->resize(newSize);
        }
    } else if (resizeMode == QQuickView::SizeRootObjectToView) {
        if (!qFuzzyCompare(q->width(), root->width()))
            root->setWidth(q->width());
        if (!qFuzzyCompare(q->height(), root->height()))
            root->setHeight(q->height());
    }
}

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

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

/*!
  \internal
 */
void QQuickView::continueExecute()
{
    Q_D(QQuickView);
    disconnect(d->component, SIGNAL(statusChanged(QQmlComponent::Status)), this, SLOT(continueExecute()));

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

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

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

    d->setRootObject(obj);
    emit statusChanged(status());
}


/*!
  \internal
*/
void QQuickViewPrivate::setRootObject(QObject *obj)
{
    Q_Q(QQuickView);
    if (root == obj)
        return;
    if (QQuickItem *sgItem = qobject_cast<QQuickItem *>(obj)) {
        root = sgItem;
        sgItem->setParentItem(q->QQuickCanvas::rootItem());
    } else {
        qWarning() << "QQuickView only supports loading of root objects that derive from QQuickItem." << endl
                   << endl
                   << "If your example is using QML 2, (such as qmlscene) and the .qml file you" << endl
                   << "loaded has 'import QtQuick 1.0' or 'import Qt 4.7', this error will occur." << endl
                   << endl
                   << "To load files with 'import QtQuick 1.0' or 'import Qt 4.7', use the" << endl
                   << "QQuickView class in the qtquick1 module." << endl;
        delete obj;
        root = 0;
    }
    if (root) {
        initialSize = rootObjectSize();
        if ((resizeMode == QQuickView::SizeViewToRootObject || !q->width() || !q->height())
                && initialSize != q->size()) {
            q->resize(initialSize);
        }
        initResize();
    }
}

/*!
  \internal
  If the \l {QTimerEvent} {timer event} \a e is this
  view's resize timer, sceneResized() is emitted.
 */
void QQuickView::timerEvent(QTimerEvent* e)
{
    Q_D(QQuickView);
    if (!e || e->timerId() == d->resizetimer.timerId()) {
        d->updateSize();
        d->resizetimer.stop();
    }
}

/*!
    \internal
    Preferred size follows the root object geometry.
*/
QSize QQuickView::sizeHint() const
{
    Q_D(const QQuickView);
    QSize rootObjectSize = d->rootObjectSize();
    if (rootObjectSize.isEmpty()) {
        return size();
    } else {
        return rootObjectSize;
    }
}

/*!
  Returns the initial size of the root object
*/
QSize QQuickView::initialSize() const
{
    Q_D(const QQuickView);
    return d->initialSize;
}

/*!
  Returns the view's root \l {QQuickItem} {item}.
 */
QQuickItem *QQuickView::rootObject() const
{
    Q_D(const QQuickView);
    return d->root;
}

/*!
  \internal
  This function handles the \l {QResizeEvent} {resize event}
  \a e.
 */
void QQuickView::resizeEvent(QResizeEvent *e)
{
    Q_D(QQuickView);
    if (d->resizeMode == SizeRootObjectToView)
        d->updateSize();

    QQuickCanvas::resizeEvent(e);
}

void QQuickView::keyPressEvent(QKeyEvent *e)
{
    QQmlProfilerService::addEvent(QQmlProfilerService::Key);

    QQuickCanvas::keyPressEvent(e);
}

void QQuickView::keyReleaseEvent(QKeyEvent *e)
{
    QQmlProfilerService::addEvent(QQmlProfilerService::Key);

    QQuickCanvas::keyReleaseEvent(e);
}

void QQuickView::mouseMoveEvent(QMouseEvent *e)
{
    QQmlProfilerService::addEvent(QQmlProfilerService::Mouse);

    QQuickCanvas::mouseMoveEvent(e);
}

void QQuickView::mousePressEvent(QMouseEvent *e)
{
    QQmlProfilerService::addEvent(QQmlProfilerService::Mouse);

    QQuickCanvas::mousePressEvent(e);
}

void QQuickView::mouseReleaseEvent(QMouseEvent *e)
{
    QQmlProfilerService::addEvent(QQmlProfilerService::Mouse);

    QQuickCanvas::mouseReleaseEvent(e);
}


QT_END_NAMESPACE