Presentation by Paweł Urban & Dariusz Seweryn. Programming with a hardware in mind is fun. IoT is no longer a future but it's around us and Bluetooth programming became our reality. We'll tell you how to play with it without having a headache, using reactive concepts.

2. DEMYSTIFYING
ANDROID'S
BLUETOOTH LOW ENERGY
Paweł Urban
Senior Software Engineer
Dariusz Seweryn
Senior Software Engineer

3. BLUETOOTH LOW ENERGY

4. BLUETOOTH LOW ENERGY
ANDROID’S NATIVE SUPPORT

5. BLUETOOTH LOW ENERGY
ANDROID’S NATIVE SUPPORT
YOUR SECRET WEAPON

6. WHY SHOULD I CARE
ABOUT BLE?

8. The Internet of Things – infographicThe Connectivist based on Cisco data

9. 2006

10. 2006 2010

11. 2006 2010 2013

12. A DEVELOPER
PERSPECTIVE

13. Jelly Bean

14. BACKWARD SUPPORT

15. BACKWARD SUPPORT

16. BACKWARD SUPPORT
BETA

17. BACKWARD SUPPORT
BETA

18. LOW ENERGY

19. GAP (GENERIC ACCESS PROFILE)

20. PERIPHERAL

21. PERIPHERAL CENTRAL

22. PERIPHERAL CENTRAL
ADVERTISE PRESENCE

23. PERIPHERAL CENTRAL
ADVERTISE PRESENCE
CONNECTION HANDSHAKE

24. CLIENT
PERIPHERAL CENTRAL
ADVERTISE PRESENCE
CONNECTION HANDSHAKE
SERVER

25. CLIENT
PERIPHERAL CENTRAL
ADVERTISE PRESENCE
CONNECTION HANDSHAKE
SERVER
READ/WRITE DATA REQ
RESPOND WITH DATA

26. GATT (Generic Attribute Profile)

27. Texas Instruments
SensorTAG

28. Peripheral device
Service A
Characteristic 1 Characteristic 2
DEVICE

29. Peripheral device
DEVICE
SENSOR
Service A
Characteristic 1 Characteristic 2

30. Peripheral device
DEVICE
SENSOR
36.6°C
SENSOR
VALUE
Service A
Characteristic 1 Characteristic 2

31. Peripheral device
DEVICE
SENSOR
36.6°C
SENSOR
VALUE
Service A
Characteristic 1 Characteristic 2
SENSOR
CONFIGURATION

32. Peripheral device
DEVICE
SENSOR
36.6°C
SENSOR
VALUE
Service A
Characteristic 1 Characteristic 2
SENSOR
CONFIGURATION
READ
WRITE
NOTIFY

33. Peripheral device
Service A
Characteristic 1 Characteristic 2
Service B
Characteristic 3 Characteristic 4
Service C
Characteristic 5 Characteristic 6
DISCOVERY

34. UUID
1 TEMPERATURE(„4E99FFF1-4B3E-11E5-9D65-0002A5D5C51B");
2 HUMIDITY(„4E99FFF2-4B3E-11E5-9D65-0002A5D5C51B");
3 TIME(„5E99FFC1-4B3E-11E5-9D65-0002A5D5C51B");
4 DEVICE_NAME(„00002a26-0000-1000-8000-00805f9b34fb”);

35. UUID
1 TEMPERATURE(„4E99FFF1-4B3E-11E5-9D65-0002A5D5C51B");
2 HUMIDITY(„4E99FFF2-4B3E-11E5-9D65-0002A5D5C51B");
3 TIME(„5E99FFC1-4B3E-11E5-9D65-0002A5D5C51B");
4 DEVICE_NAME(„00002a26-0000-1000-8000-00805f9b34fb”);
128-bit

36. UUID
1 TEMPERATURE(„4E99FFF1-4B3E-11E5-9D65-0002A5D5C51B");
2 HUMIDITY(„4E99FFF2-4B3E-11E5-9D65-0002A5D5C51B");
3 TIME(„5E99FFC1-4B3E-11E5-9D65-0002A5D5C51B");
4 DEVICE_NAME(„00002a26-0000-1000-8000-00805f9b34fb”);
16-bit

37. THE SCARY PART

38. BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
final boolean startLeScan = bluetoothAdapter.startLeScan(leScanCallback);
BluetoothAdapter.LeScanCallback leScanCallback = new BluetoothAdapter.LeScanCallback() {
@Override public void onLeScan(BluetoothDevice device, int rssi, byte[] scanRecord) {
// processing results
}
};
bluetoothAdapter.stopLeScan(leScanCallback);
SCAN

39. BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
final boolean startLeScan = bluetoothAdapter.startLeScan(leScanCallback);
BluetoothAdapter.LeScanCallback leScanCallback = new BluetoothAdapter.LeScanCallback() {
@Override public void onLeScan(BluetoothDevice device, int rssi, byte[] scanRecord) {
// processing results
}
};
bluetoothAdapter.stopLeScan(leScanCallback);
SCAN

40. BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
final boolean startLeScan = bluetoothAdapter.startLeScan(leScanCallback);
BluetoothAdapter.LeScanCallback leScanCallback = new BluetoothAdapter.LeScanCallback() {
@Override public void onLeScan(BluetoothDevice device, int rssi, byte[] scanRecord) {
// processing results
}
};
bluetoothAdapter.stopLeScan(leScanCallback);
SCAN

41. BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
final boolean startLeScan = bluetoothAdapter.startLeScan(leScanCallback);
BluetoothAdapter.LeScanCallback leScanCallback = new BluetoothAdapter.LeScanCallback() {
@Override public void onLeScan(BluetoothDevice device, int rssi, byte[] scanRecord) {
// processing results
}
};
bluetoothAdapter.stopLeScan(leScanCallback);
SCAN

42. BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
final boolean startLeScan = bluetoothAdapter.startLeScan(
new UUID[]{ UUID.fromString(…) }, leScanCallback);
BluetoothAdapter.LeScanCallback leScanCallback = new BluetoothAdapter.LeScanCallback() {
@Override public void onLeScan(BluetoothDevice device, int rssi, byte[] scanRecord) {
// processing results
}
};
bluetoothAdapter.stopLeScan(leScanCallback);
SCAN

43. BluetoothDevice remoteDevice = bluetoothAdapter.getRemoteDevice(getEnteredMacAddress());
BluetoothGatt bluetoothGatt = remoteDevice.connectGatt(context, false, callback);
BluetoothGattCallback callback = new BluetoothGattCallback() {
@Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
if (status == BluetoothGatt.GATT_SUCCESS) {
if (newState == BluetoothProfile.STATE_CONNECTED) {
// You are connected!
} else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
// Disconnected
bluetoothGatt.close();
}
} else {
// Maybe disconnected?
onDisconnectRequested();
}
}
};
CONNECTION

44. BluetoothDevice remoteDevice = bluetoothAdapter.getRemoteDevice(getEnteredMacAddress());
BluetoothGatt bluetoothGatt = remoteDevice.connectGatt(context, false, callback);
BluetoothGattCallback callback = new BluetoothGattCallback() {
@Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
if (status == BluetoothGatt.GATT_SUCCESS) {
if (newState == BluetoothProfile.STATE_CONNECTED) {
// You are connected!
} else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
// Disconnected
bluetoothGatt.close();
}
} else {
// Maybe disconnected?
onDisconnectRequested();
}
}
};
CONNECTION

45. BluetoothDevice remoteDevice = bluetoothAdapter.getRemoteDevice(getEnteredMacAddress());
BluetoothGatt bluetoothGatt = remoteDevice.connectGatt(context, false, callback);
BluetoothGattCallback callback = new BluetoothGattCallback() {
@Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
if (status == BluetoothGatt.GATT_SUCCESS) {
if (newState == BluetoothProfile.STATE_CONNECTED) {
// You are connected!
} else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
// Disconnected
bluetoothGatt.close();
}
} else {
// Maybe disconnected?
onDisconnectRequested();
}
}
};
CONNECTION

46. BluetoothDevice remoteDevice = bluetoothAdapter.getRemoteDevice(getEnteredMacAddress());
BluetoothGatt bluetoothGatt = remoteDevice.connectGatt(context, false, callback);
BluetoothGattCallback callback = new BluetoothGattCallback() {
@Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
if (status == BluetoothGatt.GATT_SUCCESS) {
if (newState == BluetoothProfile.STATE_CONNECTED) {
// You are connected!
} else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
// Disconnected
bluetoothGatt.close();
}
} else {
// Maybe disconnected?
onDisconnectRequested();
}
}
};
CONNECTION

47. BluetoothDevice remoteDevice = bluetoothAdapter.getRemoteDevice(getEnteredMacAddress());
BluetoothGatt bluetoothGatt = remoteDevice.connectGatt(context, false, callback);
BluetoothGattCallback callback = new BluetoothGattCallback() {
@Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
if (status == BluetoothGatt.GATT_SUCCESS) {
if (newState == BluetoothProfile.STATE_CONNECTED) {
// You are connected!
} else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
// Disconnected
bluetoothGatt.close();
}
} else {
// Maybe disconnected?
onDisconnectRequested();
}
}
};
CONNECTION

48. boolean startedDiscovering = bluetoothGatt.discoverServices();
@Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
BluetoothGattService service = gatt.getService(serviceUUID);
BluetoothGattCharacteristic characteristic
= service.getCharacteristic(characteristicUUID);
boolean startedReadOperation = gatt.readCharacteristic(characteristic);
// ...
} else {
// ...
}
}
@Override
public void onCharacteristicRead(BluetoothGatt gatt,
BluetoothGattCharacteristic characteristic, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
byte[] characteristicValue = characteristic.getValue();
} else {
// ...
}
}
READING DATA

49. boolean startedDiscovering = bluetoothGatt.discoverServices();
@Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
BluetoothGattService service = gatt.getService(serviceUUID);
BluetoothGattCharacteristic characteristic
= service.getCharacteristic(characteristicUUID);
boolean startedReadOperation = gatt.readCharacteristic(characteristic);
// ...
} else {
// ...
}
}
@Override
public void onCharacteristicRead(BluetoothGatt gatt,
BluetoothGattCharacteristic characteristic, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
byte[] characteristicValue = characteristic.getValue();
} else {
// ...
}
}
READING DATA

50. boolean startedDiscovering = bluetoothGatt.discoverServices();
@Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
BluetoothGattService service = gatt.getService(serviceUUID);
BluetoothGattCharacteristic characteristic
= service.getCharacteristic(characteristicUUID);
boolean startedReadOperation = gatt.readCharacteristic(characteristic);
// ...
} else {
// ...
}
}
@Override
public void onCharacteristicRead(BluetoothGatt gatt,
BluetoothGattCharacteristic characteristic, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
byte[] characteristicValue = characteristic.getValue();
} else {
// ...
}
}
READING DATA

51. boolean startedDiscovering = bluetoothGatt.discoverServices();
@Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
BluetoothGattService service = gatt.getService(serviceUUID);
BluetoothGattCharacteristic characteristic
= service.getCharacteristic(characteristicUUID);
boolean startedReadOperation = gatt.readCharacteristic(characteristic);
// ...
} else {
// ...
}
}
@Override
public void onCharacteristicRead(BluetoothGatt gatt,
BluetoothGattCharacteristic characteristic, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
byte[] characteristicValue = characteristic.getValue();
} else {
// ...
}
}
READING DATA

52. @Override
void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic)
@Override
void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status)
@Override
void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status)
@Override
void onConnectionStateChange(BluetoothGatt gatt, int status, int newState)
@Override
void onDescriptorRead(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status)
@Override
void onDescriptorWrite(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status)
@Override
void onServicesDiscovered(BluetoothGatt gatt, int status)
@Override
void onMtuChanged(BluetoothGatt gatt, int mtu, int status)
@Override
void onReadRemoteRssi(BluetoothGatt gatt, int rssi, int status)
@Override
void onReliableWriteCompleted(BluetoothGatt gatt, int status)

53. DOES IT HAVETO BE
HARD?

54. RxAndroidBLE
No! Just use

55. RXJAVA

56. OBSERVABLE
RXJAVA

57. Device Scanning
OBSERVABLE

58. Device Scanning
Scanned device

59. Device Scanning
Scanned device

60. Device Scanning
Scanned device

61. Device Scanning

62. Device Scanning
Establish Connection

63. Device Scanning
Connecting to device
Establish Connection

64. Device Scanning
Connecting to device
Establish Connection

65. Read Characteristic
Device Scanning
Connecting to device
Establish Connection

66. Device Scanning
Connecting to device
Reading CharacteristicValue
Read Characteristic
Establish Connection

67. Device Scanning
Connecting to device
Reading CharacteristicValue
Read Characteristic
Establish Connection

68. Declaration of what
we want to achieve
Device Scanning
Connecting to device
Reading CharacteristicValue
Read Characteristic
Establish Connection

69. Device Scanning
Connecting to device
Reading CharacteristicValue
Read Characteristic
Establish Connection

70. Device Scanning
Connecting to device
Some action
Do something
Establish Connection

71. Device Scanning
Connecting to device
Some action
Do something
Establish Connection

72. Device Scanning
Connecting to device
Some action
Do something
Establish Connection

73. THE DEMO

74. SAYTHAT AGAIN?

75. Q&As?

76. LET’S CHAT!
@DSeweryn
+PawełUrban
https://git.io/vw8PM

77. ThankYou!
@DSeweryn +PawełUrban
https://git.io/vw8PM