Contenido
Parte # 2 (conectar / desconectar)
Parte # 3 (lectura / escritura)
Parte # 4 (vinculación), estás aquí
En el artículo anterior, descubrimos las operaciones de lectura / escritura, habilitar / deshabilitar notificaciones y poner en cola los comandos. En este artículo hablaremos sobre el emparejamiento de dispositivos ( Nota del traductor; además, utilizaré el término "vinculación" ).
Vinculación
Algunos dispositivos requieren uniones para funcionar correctamente. Técnicamente, esto significa que las claves de cifrado se generan, intercambian y almacenan para un intercambio seguro de datos. Al iniciar el procedimiento de vinculación, Android puede solicitar al usuario su consentimiento, código PIN o frase de contraseña. En las próximas conexiones, Android ya sabe que el dispositivo está emparejado y las claves de cifrado se intercambian en secreto sin la intervención del usuario. El uso de vinculación hace que la conexión al dispositivo sea más segura porque la conexión está encriptada.
bonding Google, , bonding. createBond()
. , iOS CoreBluetooth
! createBond()
? , , bonding, . Bluetooth , – bonding. . , , , .
bonding:
Android bonding. Android bonding , , bonding, / .
createBond()
(. : , - . , Samsung -, );
, bonding. / , . Android bonding;
bonding. bonding , ;
, ,
createBond()
bonding . .
bonding?
, bonding:
, , bonding, ;
«» . , bonding. / , bonding – /
INSUFFICIENT_AUTHENTICATION
. iOS.
bonding
createBond()
. , iOS, . Bluetooth .
.
Bonding
bonding , onConnectionStateChange
bonding BOND_BONDING
. bonding , discoverServices()
, bonding ! . onConnectionStateChanged
:
// Take action depending on the bond state
if(bondstate == BOND_NONE || bondstate == BOND_BONDED) {
// Connected to device, now proceed to discover it's services
...
} else if (bondstate == BOND_BONDING) {
// Bonding process has already started let it complete
Log.i(TAG, "waiting for bonding to complete");
}
, bonding, BroadcastReceiver
ACTION_BOND_STATE_CHANGED
connectGatt
. bonding.
context.registerReceiver(bondStateReceiver,
new IntentFilter(ACTION_BOND_STATE_CHANGED));
private final BroadcastReceiver bondStateReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
final String action = intent.getAction();
final BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
// Ignore updates for other devices
if (bluetoothGatt == null || !device.getAddress().equals(bluetoothGatt.getDevice().getAddress()))
return;
// Check if action is valid
if(action == null) return;
// Take action depending on new bond state
if (action.equals(ACTION_BOND_STATE_CHANGED)) {
final int bondState = intent.getIntExtra(EXTRA_BOND_STATE, ERROR);
final int previousBondState = intent.getIntExtra(BluetoothDevice.EXTRA_PREVIOUS_BOND_STATE, -1);
switch (bondState) {
case BOND_BONDING:
// Bonding started
...
break;
case BOND_BONDED:
// Bonding succeeded
...
break;
case BOND_NONE:
// Oh oh
...
break;
}
}
}
};
bonding, (service discovery), , :
case BOND_BONDED:
// Bonding succeeded
Log.d(TAG, "bonded");
// Check if there are services
if(bluetoothGatt.getServices().isEmpty()) {
// No services discovered yet
bleHandler.post(new Runnable() {
@Override
public void run() {
Log.d(TAG, String.format("discovering services of '%s'", getName()));
boolean result = bluetoothGatt.discoverServices();
if (!result) {
Log.e(TAG, "discoverServices failed to start");
}
}
});
}
, bonding .
Bonding /
bonding / , / GATT_INSUFFICIENT_AUTHENTICATION
. Android-6, 7 onCharacteristicRead
/onCharacteristicWrite
, bonding Android. Android-8 Android bonding. Android-6, 7 / . , bonding.
, :
public void onCharacteristicRead(BluetoothGatt gatt, final BluetoothGattCharacteristic characteristic, int status) {
// Perform some checks on the status field
if (status != GATT_SUCCESS) {
if (status == GATT_INSUFFICIENT_AUTHENTICATION ) {
// Characteristic encrypted and needs bonding,
// So retry operation after bonding completes
// This only happens on Android 5/6/7
Log.w(TAG, "read needs bonding, bonding in progress");
return;
} else {
Log.e(TAG, String.format(Locale.ENGLISH,"ERROR: Read failed for characteristic: %s, status %d", characteristic.getUuid(), status));
completedCommand();
return;
}
}
...
bonding , :
case BOND_BONDED:
// Bonding succeeded
Log.d(TAG, "bonded");
// Check if there are services
...
// If bonding was triggered by a read/write, we must retry it
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.O) {
if (commandQueueBusy && !manuallyBonding) {
bleHandler.postDelayed(new Runnable() {
@Override
public void run() {
Log.d(TAG, "retrying command after bonding");
retryCommand();
}
}, 50);
}
}
bonding
, createBond
, , . , ? iOS createBond()
, – bonding , iOS. iOS. BLE , createBond()
- .
createBond
, , bonding BroadcastReceiver
. (bonding ), createBond()
, bonding .
createBond()
– . BluetoothDevice
MAC-, (bonding). … ! (. : , , , ).
bonding
Android, Bluetooth . , bonding .
.
, bonding . , removeBond()
, Java:
try {
Method method = device.getClass().getMethod("removeBond", (Class[]) null);
result = (boolean) method.invoke(device, (Object[]) null);
if (result) {
Log.i(TAG, "Successfully removed bond");
}
return result;
} catch (Exception e) {
Log.e(TAG, "ERROR: could not remove bond");
e.printStackTrace();
return false;
}
bonding
BLE bonding . , bonding :
bonding
B bonding
, bonding .
bonding BOND_NONE
BroadcastReceiver
. bonding, :
case BOND_NONE:
if(previousBondState == BOND_BONDING) {
// Bonding failed
...
} else {
// Bond lost
...
}
disconnect();
break;
bonding, , . , Android bonding. .
, . bonding, , Bluetooth . bonding, Android , , . .
Pairing
. : «pairing», «» - .
Android bonding, . «», (. : Samsung-S9, Android-10, , , , ). Google ( , Android ), .
Pairing :
;
;
« »;
Bluetooth .
«» 60 . , . , , . , . UI -! () ! Samsung - ( JustWorks) , . PIN- . . !
, , , . , . :
public void startPairingPopupHack() {
String manufacturer = Build.MANUFACTURER;
if(!manufacturer.equals("samsung")) {
bluetoothAdapter.startDiscovery();
callBackHandler.postDelayed(new Runnable() {
@Override
public void run() {
Log.d(TAG, "popup hack completed");
bluetoothAdapter.cancelDiscovery();
}
}, 1000);
}
}
– BLE . .
, bonding !
…
BLE Android (. : -, BLE Android, ). BLE . BLE, . !
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