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/****************************************************************************
**
** Copyright (C) 2015 Canonical Limited and/or its subsidiary(-ies)
** Contact: http://www.qt.io/licensing/
**
** This file is part of the demonstration applications of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of The Qt Company Ltd nor the names of its
** contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include <qqmlextensionplugin.h>
#include <qqmlengine.h>
#include <qquickimageprovider.h>
#include <QDebug>
#include <QImage>
#include <QThreadPool>
class AsyncImageResponse : public QQuickImageResponse, public QRunnable
{
public:
AsyncImageResponse(const QString &id, const QSize &requestedSize)
: m_id(id), m_requestedSize(requestedSize), m_texture(0)
{
setAutoDelete(false);
}
QQuickTextureFactory *textureFactory() const
{
return m_texture;
}
void run()
{
QImage image(50, 50, QImage::Format_RGB32);
if (m_id == "slow") {
qDebug() << "Slow, red, sleeping for 5 seconds";
QThread::sleep(5);
image.fill(Qt::red);
} else {
qDebug() << "Fast, blue, sleeping for 1 second";
QThread::sleep(1);
image.fill(Qt::blue);
}
if (m_requestedSize.isValid())
image = image.scaled(m_requestedSize);
m_texture = QQuickTextureFactory::textureFactoryForImage(image);
emit finished();
}
QString m_id;
QSize m_requestedSize;
QQuickTextureFactory *m_texture;
};
class AsyncImageProvider : public QQuickAsyncImageProvider
{
public:
QQuickImageResponse *requestImageResponse(const QString &id, const QSize &requestedSize)
{
AsyncImageResponse *response = new AsyncImageResponse(id, requestedSize);
pool.start(response);
return response;
}
private:
QThreadPool pool;
};
class ImageProviderExtensionPlugin : public QQmlExtensionPlugin
{
Q_OBJECT
Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QQmlExtensionInterface")
public:
void registerTypes(const char *uri)
{
Q_UNUSED(uri);
}
void initializeEngine(QQmlEngine *engine, const char *uri)
{
Q_UNUSED(uri);
engine->addImageProvider("async", new AsyncImageProvider);
}
};
#define QQmlExtensionInterface_iid "org.qt-project.Qt.QQmlExtensionInterface"
#include "imageresponseprovider.moc"
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