imageresponseprovider.cpp Example File

imageresponseprovider/imageresponseprovider.cpp
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#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) { setAutoDelete(false); } QQuickTextureFactory *textureFactory() const { return QQuickTextureFactory::textureFactoryForImage(m_image); } void run() { m_image = QImage(50, 50, QImage::Format_RGB32); if (m_id == "slow") { qDebug() << "Slow, red, sleeping for 5 seconds"; QThread::sleep(5); m_image.fill(Qt::red); } else { qDebug() << "Fast, blue, sleeping for 1 second"; QThread::sleep(1); m_image.fill(Qt::blue); } if (m_requestedSize.isValid()) m_image = m_image.scaled(m_requestedSize); emit finished(); } QString m_id; QSize m_requestedSize; QImage m_image; }; 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 QQmlExtensionInterface_iid) public: void registerTypes(const char *uri) { Q_UNUSED(uri); } void initializeEngine(QQmlEngine *engine, const char *uri) { Q_UNUSED(uri); engine->addImageProvider("async", new AsyncImageProvider); } }; #include "imageresponseprovider.moc"