Introduce Loader item.

The Loader item takes the qml/qmlItem functionality from Item and
moves it to a specialized subclass.

1 files changed, 188 insertions, 0 deletions

diff --git a/src/declarative/fx/qfxloader.cpp b/src/declarative/fx/qfxloader.cpp
new file mode 100644
index 0000000..7cf85af
--- /dev/null
+++ b/src/declarative/fx/qfxloader.cpp
@@ -0,0 +1,188 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (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 either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** 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 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** 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
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qfxloader_p.h"
+#include <private/qmlengine_p.h>
+
+QT_BEGIN_NAMESPACE
+
+QFxLoaderPrivate::QFxLoaderPrivate()
+: item(0), qmlcomp(0)
+{
+}
+
+QFxLoaderPrivate::~QFxLoaderPrivate()
+{
+}
+
+QML_DEFINE_TYPE(Qt,4,6,(QT_VERSION&0x00ff00)>>8,Loader,QFxLoader)
+
+/*!
+    \qmlclass Loader
+    \inherits Item
+
+    \brief The Loader item allows you to dynamically load an Item-based
+    subtree from a QML URL.
+ */
+
+/*!
+    \internal
+    \class QFxLoader
+    \qmlclass Loader
+ */
+
+/*!
+    Create a new QFxLoader instance.
+ */
+QFxLoader::QFxLoader(QFxItem *parent)
+  : QFxItem(*(new QFxLoaderPrivate), parent)
+{
+}
+
+/*!
+    Destroy the loader instance.
+ */
+QFxLoader::~QFxLoader()
+{
+}
+
+/*!
+    \internal
+    \fn void QFxItem::sourceChanged()
+    This signal is emitted whenever the item's dynamic QML
+    source url changes.
+ */
+
+/*!
+    \qmlproperty url Loader::source
+    This property holds the dynamic URL of the QML for the item.
+
+    This property is used for dynamically loading QML into the
+    item.
+*/
+QUrl QFxLoader::source() const
+{
+    Q_D(const QFxLoader);
+    return d->source;
+}
+
+void QFxLoader::setSource(const QUrl &url)
+{
+    Q_D(QFxLoader);
+    if (d->source == url)
+        return;
+
+    if (!d->source.isEmpty()) {
+        QHash<QString, QFxItem *>::Iterator iter = d->cachedChildren.find(d->source.toString());
+        if (iter != d->cachedChildren.end())
+            (*iter)->setOpacity(0.);
+    }
+
+    d->source = url;
+    d->item = 0;
+
+    if (d->source.isEmpty()) {
+        emit sourceChanged();
+        return;
+    }
+
+    QHash<QString, QFxItem *>::Iterator iter = d->cachedChildren.find(d->source.toString());
+    if (iter != d->cachedChildren.end()) {
+        (*iter)->setOpacity(1.);
+        d->item = (*iter);
+        emit sourceChanged();
+    } else {
+        d->qmlcomp =
+            new QmlComponent(qmlEngine(this), d->source, this);
+        if (!d->qmlcomp->isLoading())
+            d->_q_sourceLoaded();
+        else
+            connect(d->qmlcomp, SIGNAL(statusChanged(QmlComponent::Status)),
+                    this, SLOT(_q_sourceLoaded()));
+    }
+}
+
+void QFxLoaderPrivate::_q_sourceLoaded()
+{
+    Q_Q(QFxLoader);
+
+    if (qmlcomp) {
+        QmlContext *ctxt = new QmlContext(qmlContext(q));
+        ctxt->addDefaultObject(q);
+
+        if (!qmlcomp->errors().isEmpty()) {
+            qWarning() << qmlcomp->errors();
+            delete qmlcomp;
+            qmlcomp = 0;
+            emit q->sourceChanged();
+            return;
+        }
+        QObject *obj = qmlcomp->create(ctxt);
+        if (!qmlcomp->errors().isEmpty())
+            qWarning() << qmlcomp->errors();
+        QFxItem *qmlChild = qobject_cast<QFxItem *>(obj);
+        if (qmlChild) {
+            qmlChild->setParentItem(q);
+            cachedChildren.insert(source.toString(), qmlChild);
+            item = qmlChild;
+        } else {
+            delete qmlChild;
+            source = QUrl();
+        }
+        delete qmlcomp;
+        qmlcomp = 0;
+        emit q->sourceChanged();
+    }
+}
+
+/*!
+    \qmlproperty url Loader::item
+    This property holds the top-level item created from source.
+*/
+QFxItem *QFxLoader::item() const
+{
+    Q_D(const QFxLoader);
+    return d->item;
+}
+
+QT_END_NAMESPACE
+
+#include "moc_qfxloader.cpp"