summaryrefslogtreecommitdiffstats
path: root/src/declarative/graphicsitems/qdeclarativeloader.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'src/declarative/graphicsitems/qdeclarativeloader.cpp')
-rw-r--r--src/declarative/graphicsitems/qdeclarativeloader.cpp517
1 files changed, 517 insertions, 0 deletions
diff --git a/src/declarative/graphicsitems/qdeclarativeloader.cpp b/src/declarative/graphicsitems/qdeclarativeloader.cpp
new file mode 100644
index 0000000..cc7f8e5
--- /dev/null
+++ b/src/declarative/graphicsitems/qdeclarativeloader.cpp
@@ -0,0 +1,517 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtDeclarative module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#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)
+{
+}
+
+QDeclarativeLoaderPrivate::~QDeclarativeLoaderPrivate()
+{
+}
+
+void QDeclarativeLoaderPrivate::itemGeometryChanged(QDeclarativeItem *resizeItem, const QRectF &newGeometry, const QRectF &oldGeometry)
+{
+ if (resizeItem == item)
+ _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);
+ } else if (item && item->isWidget()) {
+ QGraphicsWidget *widget = static_cast<QGraphicsWidget*>(item);
+ widget->installEventFilter(q);
+ }
+ _q_updateSize();
+}
+
+/*!
+ \qmlclass Loader QDeclarativeLoader
+ \since 4.7
+ \inherits Item
+
+ \brief The Loader item allows dynamically loading an Item-based
+ subtree from a URL or Component.
+
+ The Loader element instantiates an item from a component. The component to
+ be instantiated may be specified directly by the \l sourceComponent
+ property, or loaded from a URL via the \l source property.
+
+ Loader can be used to delay the creation of a component until it
+ is required. For example, this loads "Page1.qml" as a component
+ into the Loader element, when the \l MouseArea is clicked:
+
+ \code
+ import Qt 4.7
+
+ Item {
+ width: 200; height: 200
+
+ MouseArea {
+ anchors.fill: parent
+ onClicked: pageLoader.source = "Page1.qml"
+ }
+
+ Loader { id: pageLoader }
+ }
+ \endcode
+
+ Note that Loader is like any other graphical Item and needs to be positioned
+ and sized accordingly to become visible. When a component is loaded, the
+ Loader is automatically resized to the size of the component.
+
+ If the Loader source is changed, any previous items instantiated
+ will be destroyed. Setting \l source to an empty string, or setting
+ sourceComponent to \e undefined
+ will destroy the currently instantiated items, freeing resources
+ and leaving the Loader empty. For example:
+
+ \code
+ pageLoader.source = ""
+ \endcode
+
+ or
+
+ \code
+ pageLoader.sourceComponent = undefined
+ \endcode
+
+ unloads "Page1.qml" and frees resources consumed by it.
+
+ \sa {dynamic-object-creation}{Dynamic Object Creation}
+*/
+
+/*!
+ \internal
+ \class QDeclarativeLoader
+ */
+
+/*!
+ Create a new QDeclarativeLoader instance.
+ */
+QDeclarativeLoader::QDeclarativeLoader(QDeclarativeItem *parent)
+ : QDeclarativeItem(*(new QDeclarativeLoaderPrivate), parent)
+{
+ Q_D(QDeclarativeLoader);
+ d->flags |= QGraphicsItem::ItemIsFocusScope;
+}
+
+/*!
+ Destroy the loader instance.
+ */
+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);
+ }
+ }
+}
+
+/*!
+ \qmlproperty url Loader::source
+ This property holds the URL of the QML component to
+ instantiate.
+
+ \sa sourceComponent, status, progress
+*/
+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 (!d->component->isLoading()) {
+ d->_q_sourceLoaded();
+ } else {
+ connect(d->component, SIGNAL(statusChanged(QDeclarativeComponent::Status)),
+ this, SLOT(_q_sourceLoaded()));
+ connect(d->component, SIGNAL(progressChanged(qreal)),
+ this, SIGNAL(progressChanged()));
+ emit statusChanged();
+ emit progressChanged();
+ emit sourceChanged();
+ emit itemChanged();
+ }
+}
+
+/*!
+ \qmlproperty Component Loader::sourceComponent
+ This property holds the \l{Component} to instantiate.
+
+ \qml
+ Item {
+ Component {
+ id: redSquare
+ Rectangle { color: "red"; width: 10; height: 10 }
+ }
+
+ Loader { sourceComponent: redSquare }
+ Loader { sourceComponent: redSquare; x: 10 }
+ }
+ \endqml
+
+ Note this value must hold a \l Component object; it cannot be a \l Item.
+
+ \sa source, progress
+*/
+
+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 (!d->component->isLoading()) {
+ d->_q_sourceLoaded();
+ } else {
+ connect(d->component, SIGNAL(statusChanged(QDeclarativeComponent::Status)),
+ this, SLOT(_q_sourceLoaded()));
+ connect(d->component, SIGNAL(progressChanged(qreal)),
+ this, SIGNAL(progressChanged()));
+ emit progressChanged();
+ emit sourceChanged();
+ emit statusChanged();
+ emit itemChanged();
+ }
+}
+
+void QDeclarativeLoader::resetSourceComponent()
+{
+ setSourceComponent(0);
+}
+
+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 *ctxt = new QDeclarativeContext(qmlContext(q));
+ ctxt->setContextObject(q);
+
+ QDeclarativeComponent *c = component;
+ QObject *obj = component->create(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.
+ 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();
+ }
+ emit q->sourceChanged();
+ emit q->statusChanged();
+ emit q->progressChanged();
+ emit q->itemChanged();
+ emit q->loaded();
+ }
+}
+
+/*!
+ \qmlproperty enumeration Loader::status
+
+ This property holds the status of QML loading. It can be one of:
+ \list
+ \o Loader.Null - no QML source has been set
+ \o Loader.Ready - the QML source has been loaded
+ \o Loader.Loading - the QML source is currently being loaded
+ \o Loader.Error - an error occurred while loading the QML source
+ \endlist
+
+ Use this status to provide an update or respond to the status change in some way.
+ For example, you could:
+
+ \e {Trigger a state change:}
+ \qml
+ State { name: 'loaded'; when: loader.status = Loader.Ready }
+ \endqml
+
+ \e {Implement an \c onStatusChanged signal handler:}
+ \qml
+ Loader {
+ id: loader
+ onStatusChanged: if (loader.status == Loader.Ready) console.log('Loaded')
+ }
+ \endqml
+
+ \e {Bind to the status value:}
+ \qml
+ Text { text: loader.status != Loader.Ready ? 'Not Loaded' : 'Loaded' }
+ \endqml
+
+ Note that if the source is a local file, the status will initially be Ready (or Error). While
+ there will be no onStatusChanged signal in that case, the onLoaded will still be invoked.
+
+ \sa progress
+*/
+
+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()
+{
+ QDeclarativeItem::componentComplete();
+ if (status() == Ready)
+ emit loaded();
+}
+
+
+/*!
+ \qmlsignal Loader::onLoaded()
+
+ This handler is called when the \l status becomes \c Loader.Ready, or on successful
+ initial load.
+*/
+
+
+/*!
+\qmlproperty real Loader::progress
+
+This property holds the progress of loading QML data from the network, from
+0.0 (nothing loaded) to 1.0 (finished). Most QML files are quite small, so
+this value will rapidly change from 0 to 1.
+
+\sa status
+*/
+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)
+ return;
+ if (QDeclarativeItem *qmlItem = qobject_cast<QDeclarativeItem*>(item)) {
+ q->setImplicitWidth(qmlItem->width());
+ if (loaderGeometryChanged && q->widthValid())
+ qmlItem->setWidth(q->width());
+ 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);
+ }
+}
+
+/*!
+ \qmlproperty Item Loader::item
+ This property holds the top-level item created from source.
+*/
+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