CardEmulation

ACTION_CHANGE_DEFAULT

String ACTION_CHANGE_DEFAULT

Activity action: ask the user to change the default card emulation service for a certain category. This will show a dialog that asks the user whether he wants to replace the current default service with the service identified with the ComponentName specified in EXTRA_SERVICE_COMPONENT, for the category specified in EXTRA_CATEGORY

Constant Value: "android.nfc.cardemulation.action.ACTION_CHANGE_DEFAULT"

CATEGORY_OTHER

String CATEGORY_OTHER

Category that can be used for all other card emulation services.

Constant Value: "other"

CATEGORY_PAYMENT

String CATEGORY_PAYMENT

Category used for NFC payment services.

Constant Value: "payment"

EXTRA_CATEGORY

String EXTRA_CATEGORY

The category extra for ACTION_CHANGE_DEFAULT.

Constant Value: "category"

EXTRA_SERVICE_COMPONENT

String EXTRA_SERVICE_COMPONENT

The service ComponentName object passed in as an extra for ACTION_CHANGE_DEFAULT.

Constant Value: "component"

SELECTION_MODE_ALWAYS_ASK

int SELECTION_MODE_ALWAYS_ASK

Return value for getSelectionModeForCategory(String).

In this mode, when using ISO-DEP card emulation with HostApduService or OffHostApduService, whenever an Application ID (AID) of this category is selected, the user is asked which service he wants to use to handle the transaction, even if there is only one matching service.

Constant Value: 1 (0x00000001)

SELECTION_MODE_ASK_IF_CONFLICT

int SELECTION_MODE_ASK_IF_CONFLICT

Return value for getSelectionModeForCategory(String).

In this mode, when using ISO-DEP card emulation with HostApduService or OffHostApduService, the user will only be asked to select a service if the Application ID (AID) selected by the reader has been registered by multiple services. If there is only one service that has registered for the AID, that service will be invoked directly.

Constant Value: 2 (0x00000002)

SELECTION_MODE_PREFER_DEFAULT

int SELECTION_MODE_PREFER_DEFAULT

Return value for getSelectionModeForCategory(String).

In this mode, the user has set a default service for this category.

When using ISO-DEP card emulation with HostApduService or OffHostApduService, if a remote NFC device selects any of the Application IDs (AIDs) that the default service has registered in this category, that service will automatically be bound to to handle the transaction.

Constant Value: 0 (0x00000000)

categoryAllowsForegroundPreference

boolean categoryAllowsForegroundPreference (String category)

Returns whether the user has allowed AIDs registered in the specified category to be handled by a service that is preferred by the foreground application, instead of by a pre-configured default. Foreground applications can set such preferences using the setPreferredService(Activity, ComponentName) method.

getAidsForService

List<String> getAidsForService (ComponentName service, 
                String category)

Retrieves the currently registered AIDs for the specified category for a service.

Note that this will only return AIDs that were dynamically registered using registerAidsForService(ComponentName, String, List) method. It will *not* return AIDs that were statically registered in the manifest.

getInstance

CardEmulation getInstance (NfcAdapter adapter)

Helper to get an instance of this class.

getSelectionModeForCategory

int getSelectionModeForCategory (String category)

Returns the service selection mode for the passed in category. Valid return values are:

SELECTION_MODE_PREFER_DEFAULT the user has requested a default service for this category, which will be preferred.

SELECTION_MODE_ALWAYS_ASK the user has requested to be asked every time what service he would like to use in this category.

SELECTION_MODE_ASK_IF_CONFLICT the user will only be asked to pick a service if there is a conflict.

isDefaultServiceForAid

boolean isDefaultServiceForAid (ComponentName service, 
                String aid)

Allows an application to query whether a service is currently the default handler for a specified ISO7816-4 Application ID.

isDefaultServiceForCategory

boolean isDefaultServiceForCategory (ComponentName service, 
                String category)

Allows an application to query whether a service is currently the default service to handle a card emulation category.

Note that if getSelectionModeForCategory(String) returns SELECTION_MODE_ALWAYS_ASK or SELECTION_MODE_ASK_IF_CONFLICT, this method will always return false. That is because in these selection modes a default can't be set at the category level. For categories where the selection mode is SELECTION_MODE_ALWAYS_ASK or SELECTION_MODE_ASK_IF_CONFLICT, use isDefaultServiceForAid(ComponentName, String) to determine whether a service is the default for a specific AID.

registerAidsForService

boolean registerAidsForService (ComponentName service, 
                String category, 
                List<String> aids)

Registers a list of AIDs for a specific category for the specified service.

If a list of AIDs for that category was previously registered for this service (either statically through the manifest, or dynamically by using this API), that list of AIDs will be replaced with this one.

Note that you can only register AIDs for a service that is running under the same UID as the caller of this API. Typically this means you need to call this from the same package as the service itself, though UIDs can also be shared between packages using shared UIDs.

removeAidsForService

boolean removeAidsForService (ComponentName service, 
                String category)

Removes a previously registered list of AIDs for the specified category for the service provided.

Note that this will only remove AIDs that were dynamically registered using the registerAidsForService(ComponentName, String, List) method. It will *not* remove AIDs that were statically registered in the manifest. If dynamically registered AIDs are removed using this method, and a statically registered AID group for the same category exists in the manifest, the static AID group will become active again.

setPreferredService

boolean setPreferredService (Activity activity, 
                ComponentName service)

Allows a foreground application to specify which card emulation service should be preferred while a specific Activity is in the foreground.

The specified Activity must currently be in resumed state. A good paradigm is to call this method in your onResume(), and to call unsetPreferredService(Activity) in your onPause().

This method call will fail in two specific scenarios:

• If the service registers one or more AIDs in the CATEGORY_PAYMENT category, but the user has indicated that foreground apps are not allowed to override the default payment service.
• If the service registers one or more AIDs in the CATEGORY_OTHER category that are also handled by the default payment service, and the user has indicated that foreground apps are not allowed to override the default payment service.

Use categoryAllowsForegroundPreference(String) to determine whether foreground apps can override the default payment service.

Note that this preference is not persisted by the OS, and hence must be called every time the Activity is resumed.

supportsAidPrefixRegistration

boolean supportsAidPrefixRegistration ()

Some devices may allow an application to register all AIDs that starts with a certain prefix, e.g. "A000000004*" to register all MasterCard AIDs. Use this method to determine whether this device supports registering AID prefixes.

unsetPreferredService

boolean unsetPreferredService (Activity activity)

Unsets the preferred service for the specified Activity.

Note that the specified Activity must still be in resumed state at the time of this call. A good place to call this method is in your onPause() implementation.