Qt IF Generator Extensions allows building a middleware layer for accessing Android Automotive Vehicle Properties. It makes use of tools and core APIs provided by the Qt Interface Framework module. It also delivers additional templates that can be used to generate additional project types:

YAML Annotations

In order to be able to access Android Automotive Vehicle Properties, additional configuration has to be provided next to the QFace IDL itself. In the Qt IF Generator Extensions the following annotations (in the accompanying YAML file) are used for Interface Object type:

• The imports tag:

  config_android_automotive:
      imports: ["android.car.VehicleAreaSeat","android.car.VehicleAreaWindow"]

  Defines a list of Android API imports that contain defines/consts related to properties handled by this interface (e.g. zone id consts). The entries will be converted into the list of imports:

  import android.car.VehicleAreaSeat;
  import android.car.VehicleAreaWindow;

• The zoneAliases tag:

  config_android_automotive:
      zoneAliases: ["DRIVER_ZONE_ID = VehicleAreaSeat.SEAT_ROW_1_LEFT | VehicleAreaSeat.SEAT_ROW_2_LEFT | VehicleAreaSeat.SEAT_ROW_2_CENTER",
                    "PASSENGER_ZONE_ID = VehicleAreaSeat.SEAT_ROW_1_RIGHT | VehicleAreaSeat.SEAT_ROW_2_RIGHT",
                    "SEAT_ALL = DRIVER_ZONE_ID | PASSENGER_ZONE_ID"]

  Defines zones aliases for individual properties e.g. to be used with zones that group multiple sub-zones. The entries will be converted into the list of Java constants:

  public static final int DRIVER_ZONE_ID = VehicleAreaSeat.SEAT_ROW_1_LEFT | VehicleAreaSeat.SEAT_ROW_2_LEFT | VehicleAreaSeat.SEAT_ROW_2_CENTER;
  public static final int PASSENGER_ZONE_ID = VehicleAreaSeat.SEAT_ROW_1_RIGHT | VehicleAreaSeat.SEAT_ROW_2_RIGHT;
  public static final int SEAT_ALL = DRIVER_ZONE_ID | PASSENGER_ZONE_ID;

• The zoneMappings tag:

  config_android_automotive:
      zoneMappings: {"" : "SEAT_ALL",
                     "Driver": "DRIVER_ZONE_ID",
                     "Passenger" : "PASSENGER_ZONE_ID"}

  Defines the zone mapping from QtIF's QML string representation to the underlying Java enum zone for Android Automotive. This will initialize a C++ map as follows:

  m_zoneMappings.insert(QStringLiteral(""), QAndroidJniObject::getStaticField<jint>(
                                                                      "io/qt/qtif/android/vehiclefunctions/QIfClimateControlSensors",
                                                                      "SEAT_ALL"));
  m_zoneMappings.insert(QStringLiteral("Driver"), QAndroidJniObject::getStaticField<jint>(
                                                                      "io/qt/qtif/android/vehiclefunctions/QIfClimateControlSensors",
                                                                      "DRIVER_ZONE_ID"));
  m_zoneMappings.insert(QStringLiteral("Passenger"), QAndroidJniObject::getStaticField<jint>(
                                                                      "io/qt/qtif/android/vehiclefunctions/QIfClimateControlSensors",
                                                                      "PASSENGER_ZONE_ID"));

In the Qt IF Generator Extensions the following annotations (in the accompanying YAML file) are used for Property Object type:

• The vhalId property:

  config_android_automotive:
      vhalId: "HVAC_AC_ON"

  Defines the related android property id, as defined in Android Automotive Vehicle Property Ids.

• The zone property:

  config_android_automotive:
      zone: ["DRIVER_ZONE_ID", "PASSENGER_ZONE_ID"]

  Defines the zone enum(s) for the related android property. The zone can be either one or more of the values defined under the interface's zoneAliases. If a zone holds multiple values, these values have to be defined as an array. The QML component can then decide which zone to control. For example:

  ClimateControl {
      id: climateControl
      zone: "Driver"
  }

  To get the value of climateControl for a given zone in QML, use the following snippet:

  property int tempValue = climateControl.zoneAt.Driver.targetTemperatureSet

• The vhalType property:

  config_android_automotive:
      vhalType: "BOOLEAN"

  A vehicle property type as defined in Vehicle Properties.

• The javaType property:

  config_android_automotive:
      javaType: "Boolean"

  The vehicle property Java type.

Structure for Generated Projects

In the generator output directory, first, a new subfolder is created and named after the module ID. All the generated files are placed in this folder. The tables below describe the files that are generated for the project types delivered by the Qt IF Generator Extensions.

Qt Remote Objects Server

This generator template shall be used together with a project that contains the Qt Services code. The server_android_carapi_qtro template is only available if qmake/CMake finds the Qt Remotes Objects module. The code produced contains:

• the code for establishing the connection
• the code that enables the JNI interface to call the Java back end logic
• default implementation of complete Java back end logic required to access Android Automotive Vehicle Properties
• Java interface that can be implemented to provide back end logic, if default implementation doesn't meet the requirements

The following diagram presents the possible use case scenarios:

• using custom implementation for accessing vehicle property
• using default implementation for accessing vehicle properties

JNI Back End

This generator template shall be used on a plugin project. The backend_android_carapi_jni template provides the production back end that can be used to access Android Automotive Vehicle Properties. The code produced contains:

• the code for setting back end plugin
• the code that enables JNI interface to actual Java back end logic
• default implementation of complete Java back end logic required to access Android Automotive Vehicle Properties
• Java interface that can be implemented to provide back end logic if default implementation doesn't meet the requirements

The following diagram presents the possible use case scenarios:

• using default implementation for accessing vehicle properties
• using custom implementation for accessing vehicle property