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// Copyright (C) 2015 Canonical Limited and/or its subsidiary(-ies)
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include <qqmlextensionplugin.h>
#include <qqmlengine.h>
#include <qquickimageprovider.h>
#include <QDebug>
#include <QImage>
#include <QThreadPool>
class AsyncImageResponseRunnable : public QObject, public QRunnable
{
Q_OBJECT
signals:
void done(QImage image);
public:
AsyncImageResponseRunnable(const QString &id, const QSize &requestedSize)
: m_id(id), m_requestedSize(requestedSize) {}
void run() override
{
auto image = QImage(50, 50, QImage::Format_RGB32);
if (m_id == QLatin1String("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);
emit done(image);
}
private:
QString m_id;
QSize m_requestedSize;
};
class AsyncImageResponse : public QQuickImageResponse
{
public:
AsyncImageResponse(const QString &id, const QSize &requestedSize, QThreadPool *pool)
{
auto runnable = new AsyncImageResponseRunnable(id, requestedSize);
connect(runnable, &AsyncImageResponseRunnable::done, this, &AsyncImageResponse::handleDone);
pool->start(runnable);
}
void handleDone(QImage image) {
m_image = image;
emit finished();
}
QQuickTextureFactory *textureFactory() const override
{
return QQuickTextureFactory::textureFactoryForImage(m_image);
}
QImage m_image;
};
class AsyncImageProvider : public QQuickAsyncImageProvider
{
public:
QQuickImageResponse *requestImageResponse(const QString &id, const QSize &requestedSize) override
{
AsyncImageResponse *response = new AsyncImageResponse(id, requestedSize, &pool);
return response;
}
private:
QThreadPool pool;
};
class ImageProviderExtensionPlugin : public QQmlEngineExtensionPlugin
{
Q_OBJECT
Q_PLUGIN_METADATA(IID QQmlEngineExtensionInterface_iid)
public:
void initializeEngine(QQmlEngine *engine, const char *uri) override
{
Q_UNUSED(uri);
engine->addImageProvider("async", new AsyncImageProvider);
}
};
#include "imageresponseprovider.moc"
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