Qt 5.9 | Qt Sensors | Creating a sensor plugin

Qt 5.9.9 Reference Documentation

# Creating a sensor plugin

## How a Sensor Plugin is Loaded

Since sensor backends are created on demand, the sensor plugin is loaded and asked to register the sensor backends it handles. The plugin should implement QSensorPluginInterface::registerSensors() and call QSensorManager::registerBackend() to register available backends. Typically the plugin will also inherit from QSensorBackendFactory and implement QSensorBackendFactory::createBackend() in order to instantiate backends it has registered.

The simplest plugin will have just once sensor backend although there is no reason that multiple sensor backends cannot be in a plugin.

An example follows.

      class MyPluginClass : public QObject, public QSensorPluginInterface, public QSensorBackendFactory
      {
          Q_OBJECT
          //Q_PLUGIN_METADATA(IID "com.qt-project.Qt.QSensorPluginInterface/1.0" FILE "plugin.json")
          Q_INTERFACES(QSensorPluginInterface)
      public:
          void registerSensors()
          {
              QSensorManager::registerBackend(QAccelerometer::type, MyBackend::id, this);
          }

          QSensorBackend *createBackend(QSensor *sensor)
          {
              if (sensor->identifier() == MyBackend::id)
                  return new MyBackend(sensor);
              return 0;
          }
      };