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 () 和调用 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() override
    {
        QSensorManager::registerBackend(QAccelerometer::sensorType, MyBackend::id, this);
    }
    QSensorBackend *createBackend(QSensor *sensor) override
    {
        if (sensor->identifier() == MyBackend::id)
            return new MyBackend(sensor);
        return 0;
    }
};