Adaptive Interface Capabilities

Designing for Different Head Units

Since each car manufacturer has different user interface style guidelines, the number of lines of text, soft and hard buttons, and images supported will vary between different types of head units. When the app first connects to the SDL Core, a RegisterAppInterface response RPC will be sent by Core with the displayCapabilities, buttonCapabilities, speechCapabilities and other properties. You should use this information to create the user interface of your SDL app.

You may access these properties on the SdlManager.systemCapabilityManager instance as of library v.4.4.

System Capability Manager Properties

The Register App Interface Response (RAIR) RPC

The RegisterAppInterface response contains information about the display type, the type of images supported, the number of text fields supported, the HMI display language, and a lot of other useful properties. The table below has a list of properties beyond those available on the system capability manager returned by the RegisterAppInterface response. Each property is optional, so you may not get data for all the parameters in the following table.

Image Specifics

Image File Types

Images may be formatted as PNG, JPEG, or BMP. Each sdlManager.getRegisterAppInterfaceResponse().getDisplayCapabilities().getImageFields() property will have a list of imageTypeSupported.

Image Sizes

If an image is uploaded that is larger than the supported size, that image will be scaled down by Core. All image sizes are available from the sdlManager.getRegisterAppInterfaceResponse().getDisplayCapabilities().getImageFields() property once the manager has started successfully.

Querying the RAIR Capabilities

An example of querying the Vr Capabilities:

sdlManager.getRegisterAppInterfaceResponse().getVrCapabilities();

System Capabilities

Most head units provide features that your app can use: making and receiving phone calls, an embedded navigation system, video and audio streaming, as well as supporting app services. To find out if the head unit supports a feature as well as more information about the feature, use the SystemCapabilityManager to query the head unit for the desired capability. Querying for capabilities is only available on head units supporting SDL Core v4.5 or greater; if connecting to older head units, the query will return null even if the head unit may support the capabilty.

Querying for System Capabilities

sdlManager.getSystemCapabilityManager().getCapability(SystemCapabilityType.APP_SERVICES, new OnSystemCapabilityListener() {
    @Override
    public void onCapabilityRetrieved(Object capability) {
        AppServicesCapabilities servicesCapabilities = (AppServicesCapabilities) capability;
    }

    @Override
    public void onError(String info) {
        <# Handle Error #>
    }
});

Subscribing to System Capability Updates

In addition getting the current system capabilities, it is also possible to register to get updates when the head unit capabilities change. Since this information must be queried from Core you must implement the OnSystemCapabilityListener. This feature is only available on head units supporting v.5.1 or greater.

Subscribe to a Capability

sdlManager.getSystemCapabilityManager().addOnSystemCapabilityListener(SystemCapabilityType.APP_SERVICES, new OnSystemCapabilityListener() {
    @Override
    public void onCapabilityRetrieved(Object capability) {
        AppServicesCapabilities servicesCapabilities = (AppServicesCapabilities) capability;
    }

    @Override
    public void onError(String info) {
        <# Handle Error #>
    }
});

GetSystemCapability getSystemCapability = new GetSystemCapability();
getSystemCapability.setSystemCapabilityType(SystemCapabilityType.APP_SERVICES);
getSystemCapability.setSubscribe(true);
sdlManager.sendRPC(getSystemCapability);