imageprovider.cpp Example File

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  #include <qqmlextensionplugin.h>

  #include <qqmlengine.h>
  #include <qquickimageprovider.h>
  #include <QImage>
  #include <QPainter>

  class ColorImageProvider : public QQuickImageProvider
  {
  public:
      ColorImageProvider()
          : QQuickImageProvider(QQuickImageProvider::Pixmap)
      {
      }

      QPixmap requestPixmap(const QString &id, QSize *size, const QSize &requestedSize)
      {
          int width = 100;
          int height = 50;

          if (size)
              *size = QSize(width, height);
          QPixmap pixmap(requestedSize.width() > 0 ? requestedSize.width() : width,
                         requestedSize.height() > 0 ? requestedSize.height() : height);
          pixmap.fill(QColor(id).rgba());

          // write the color name
          QPainter painter(&pixmap);
          QFont f = painter.font();
          f.setPixelSize(20);
          painter.setFont(f);
          painter.setPen(Qt::black);
          if (requestedSize.isValid())
              painter.scale(requestedSize.width() / width, requestedSize.height() / height);
          painter.drawText(QRectF(0, 0, width, height), Qt::AlignCenter, id);

          return pixmap;
      }
  };

  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("colors", new ColorImageProvider);
      }

  };

  #include "imageprovider.moc"