第1回 MOSA Tech Meetingの発表資料。 GitHub https://github.com/murakami/workbook/tree/master/ios/Wibree Cocoa練習帳 http://www.bitz.co.jp/weblog/

1. BLUETOOTH LEを使った、
すれ違い通信
2014.2.25
Bitz Co., Ltd.

2. •村上幸雄
•@m_yukio
•ビッツ有限会社
http://www.bitz.co.jp/
今回のサンプルコードは以下のURL.
https://github.com/murakami/workbook/tree/master/ios/Wibree

3. Bluetoothは、省電力な電波を使った無線通信
で、最新の4.xでは対応機器は次の3つに分類さ
れます。
分類
Bluetooth Smart
Bluetooth Smart Ready
Bluetooth
説明
4.0で追加されたBluetooth Low Energyのみ対
応。
Bluetooth LEと従来のBluetoothの両方に対
応。
従来のBluetoothのみ対応。

4. iOSでBluetoothに対応する方法を整理してみます。
Bluetoothの種類
説明
MFi機器に対してExternal Accessory
Frameworkで通信。
従来のBLuetooth
Game Kit
Bluetooth LE
Core Bluetooth Framework
iOSでは、無関係の機器と自由に通信したいのならBluetooth LEという事にな
るかと思います。

5. すれ違い通信
Bluetooth LE
識別子
識別子
識別子を交換

6. Service
UUID
Central
発見
Peripheral
Advertise
Peripheralが対応しているService UUIDをAdvertiseする。
Centralは探しているService UUIDがないか調査する。
Centralが見つけられたら、Peripheralに対して接続要求を出
し、受けいれるとデータ通信が可能になる。
サンプルコードでは、識別子のCharacteristic UUIDを問い合わ
せて、識別子を受け取っている。

7. SAMPLE CODE

8. Central Managerの用意
self.centralManager = [[CBCentralManager alloc] initWithDelegate:self
queue:dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)];
Peripheralを探す
- (void)centralManagerDidUpdateState:(CBCentralManager *)central
{
if (central.state != CBCentralManagerStatePoweredOn) {
return;
}
[self scan];
}
!
探すサービスUUID
- (void)scan
{
[self.centralManager scanForPeripheralsWithServices:
@[[CBUUID UUIDWithString:WIBREE_SERVICE_UUID]]
options:@{ CBCentralManagerScanOptionAllowDuplicatesKey : @YES }];
}

9. Peripheralが見つかったので接続する
- (void)centralManager:(CBCentralManager *)central
didDiscoverPeripheral:(CBPeripheral *)peripheral
advertisementData:(NSDictionary *)advertisementData
RSSI:(NSNumber *)RSSI
{
if (self.discoveredPeripheral != peripheral) {
self.discoveredPeripheral = peripheral;
[self.centralManager connectPeripheral:peripheral options:nil];
}
}
サービスUUIDで検索
- (void)centralManager:(CBCentralManager *)central
didConnectPeripheral:(CBPeripheral *)peripheral
{
[self.centralManager stopScan];
[self.data setLength:0];
peripheral.delegate = self;
[peripheral discoverServices:@[[CBUUID UUIDWithString:WIBREE_SERVICE_UUID]]];
}

10. キャラクタリスティックUUIDで検索
- (void)peripheral:(CBPeripheral *)peripheral
didDiscoverServices:(NSError *)error
{
if (error) {
[self cleanup];
return;
}
for (CBService *service in peripheral.services) {
[peripheral discoverCharacteristics:
@[[CBUUID UUIDWithString:WIBREE_CHARACTERISTIC_UUID]]
forService:service];
}
}
!
- (void)peripheral:(CBPeripheral *)peripheral
didDiscoverCharacteristicsForService:(CBService *)service
error:(NSError *)error
{
if (error) {
[self cleanup];
return;
}
for (CBCharacteristic *characteristic in service.characteristics) {
if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:
WIBREE_CHARACTERISTIC_UUID]]) {
[peripheral setNotifyValue:YES forCharacteristic:characteristic];
}
}
}

11. 識別子を受け取る
- (void)peripheral:(CBPeripheral *)peripheral
didUpdateValueForCharacteristic:(CBCharacteristic *)characteristic
error:(NSError *)error
{
NSString *stringFromData = [[NSString alloc]
initWithData:characteristic.value encoding:NSUTF8StringEncoding];
if ([stringFromData isEqualToString:@"EOM"]) {
NSString
*uniqueIdentifier = [[NSString alloc]
initWithData:self.data encoding:NSUTF8StringEncoding];
dispatch_async(dispatch_get_main_queue(), ^{
[self _notifyParserDidDiscoverUUID:uniqueIdentifier];
});
[peripheral setNotifyValue:NO forCharacteristic:characteristic];
[self.centralManager cancelPeripheralConnection:peripheral];
}
[self.data appendData:characteristic.value];
}
!
- (void)peripheral:(CBPeripheral *)peripheral
didUpdateNotificationStateForCharacteristic:(CBCharacteristic *)characteristic
error:(NSError *)error
{
if (![characteristic.UUID isEqual:[CBUUID
UUIDWithString:WIBREE_CHARACTERISTIC_UUID]]) {
return;
}
if (! characteristic.isNotifying) {
[self.centralManager cancelPeripheralConnection:peripheral];
}
}

12. Peripheral Managerの用意
self.peripheralManager = [[CBPeripheralManager alloc] initWithDelegate:self
queue:dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)];
[self.peripheralManager startAdvertising:
見つけてもらうサービスUUID
@{ CBAdvertisementDataServiceUUIDsKey :
@[[CBUUID UUIDWithString:WIBREE_SERVICE_UUID]] }];
Peripheralが利用可能
- (void)peripheralManagerDidUpdateState:(CBPeripheralManager *)peripheral
{
if (peripheral.state != CBPeripheralManagerStatePoweredOn) {
return;
}
self.transferCharacteristic = [[CBMutableCharacteristic alloc]
initWithType:[CBUUID UUIDWithString:WIBREE_CHARACTERISTIC_UUID]
properties:CBCharacteristicPropertyNotify
value:nil
permissions:CBAttributePermissionsReadable];
CBMutableService *transferService = [[CBMutableService alloc]
initWithType:[CBUUID UUIDWithString:WIBREE_SERVICE_UUID]
primary:YES];
transferService.characteristics = @[self.transferCharacteristic];
[self.peripheralManager addService:transferService];
}

13. 識別子の送信
- (void)peripheralManager:(CBPeripheralManager *)peripheral
central:(CBCentral *)central
didSubscribeToCharacteristic:(CBCharacteristic *)characteristic
{
self.dataToSend = [[Document sharedDocument].uniqueIdentifier dataUsingEncoding:NSUTF8StringEncoding];
self.sendDataIndex = 0;
[self sendData];
}
!
- (void)sendData
{
static BOOL sendingEOM = NO;
if (sendingEOM) {
BOOL didSend = [self.peripheralManager
updateValue:[@"EOM" dataUsingEncoding:NSUTF8StringEncoding]
forCharacteristic:self.transferCharacteristic onSubscribedCentrals:nil];
if (didSend) sendingEOM = NO;
return;
}
if (self.sendDataIndex >= self.dataToSend.length) return;
BOOL didSend = YES;
while (didSend) {
NSInteger amountToSend = self.dataToSend.length - self.sendDataIndex;
if (amountToSend > NOTIFY_MTU) amountToSend = NOTIFY_MTU;
NSData *chunk = [NSData dataWithBytes:self.dataToSend.bytes+self.sendDataIndex length:amountToSend];
didSend = [self.peripheralManager updateValue:chunk
forCharacteristic:self.transferCharacteristic onSubscribedCentrals:nil];
if (!didSend) return;
NSString *stringFromData = [[NSString alloc] initWithData:chunk encoding:NSUTF8StringEncoding];
self.sendDataIndex += amountToSend;
if (self.sendDataIndex >= self.dataToSend.length) {
sendingEOM = YES;
BOOL eomSent = [self.peripheralManager updateValue:
[@"EOM" dataUsingEncoding:NSUTF8StringEncoding]
forCharacteristic:self.transferCharacteristic onSubscribedCentrals:nil];
if (eomSent) sendingEOM = NO;
return;
}
}
}
!
- (void)peripheralManagerIsReadyToUpdateSubscribers:(CBPeripheralManager *)peripheral
{
[self sendData];
}

14. バックグラウンドで動かすには
Info.plistのRequired background modesでApp
communicates using CoreBluetoothを設定。
Info.plistのRequired background modesでApp
shares data using CoreBluetoothを設定。

15. Core Bluetooth使用時の課題
数分単位の周期でしたバックグラウンドで動かな
いし、動いても数秒。
なので、実際のすれ違い通信は難しい。

16. iBeaconを試してみる。
CoreBluetoothでビーコンを実装。
CoreLocationでビーコンを検出。
常に検出できるみたい。

17. iBeaconを探す
/* CLLocationManagerを生成 */
self.locationManager = [[CLLocationManager alloc] init];
self.locationManager.delegate = self;
if (! self.locationManager) {
/* CLLocationManagerの初期化失敗 */
self.state = kBeaconCentralStateError;
self.error = [self _errorWithCode:kBeaconCentralResponseParserGenericError
localizedDescription:@"CLLocationManagerの初期化に失敗しました。"];
}
return;
探すビーコンのUUID
!
/* ビーコン領域を生成 */
NSUUID *uuid = [[NSUUID alloc] initWithUUIDString:BEACON_SERVICE_UUID];
self.beaconRegion = [[CLBeaconRegion alloc] initWithProximityUUID:uuid
identifier:@"demo.Wibree.BeaconCentralResponseParser"];
if (! self.beaconRegion) {
/* ビーコン領域の初期化失敗 */
self.state = kBeaconCentralStateError;
self.error = [self _errorWithCode:kBeaconCentralResponseParserGenericError
localizedDescription:@"ビーコン領域の初期化に失敗しました。"];
}
self.locationManager = nil;
return;
!
/* ビーコン領域の出入りを監視 */
[self.locationManager startMonitoringForRegion:self.beaconRegion];
!
/* 距離を監視 */
[self.locationManager startRangingBeaconsInRegion:self.beaconRegion];

18. 検出
領域に入る
- (void)locationManager:(CLLocationManager *)manager didEnterRegion:(CLRegion *)region
{
DBGMSG(@"%s", __func__);
if ([self.delegate respondsToSelector:@selector(beaconCentralResponseParser:didEnterRegion:)]) {
[self.delegate beaconCentralResponseParser:self didEnterRegion:region];
}
領域から外れる
}
!
- (void)locationManager:(CLLocationManager *)manager didExitRegion:(CLRegion *)region
{
DBGMSG(@"%s", __func__);
if ([self.delegate respondsToSelector:@selector(beaconCentralResponseParser:didExitRegion:)]) {
[self.delegate beaconCentralResponseParser:self didExitRegion:region];
}
}
距離を監視
!
-(void)locationManager:(CLLocationManager *)manager
{
}
!
didRangeBeacons:(NSArray *)beacons
inRegion:(CLBeaconRegion *)region
DBGMSG(@"%s", __func__);
if ([self.delegate respondsToSelector:@selector(beaconCentralResponseParser:didRangeBeacons:inRegion:)]) {
[self.delegate beaconCentralResponseParser:self didRangeBeacons:beacons inRegion:region];
}
- (void)locationManager:(CLLocationManager *)manager
monitoringDidFailForRegion:(CLRegion *)region
withError:(NSError *)error
{
DBGMSG(@"%s region:%@", __func__, region);
DBGMSG(@"%s error:%@", __func__, error);
}

19. 見つけてほしいUUIDを告知
/* CBPeripheralManagerを生成 */
self.peripheralManager = [[CBPeripheralManager alloc] initWithDelegate:self
queue:dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)];
if (! self.peripheralManager) {
/* CBPeripheralManagerの初期化失敗 */
self.state = kBeaconPeripheralStateError;
self.error = [self _errorWithCode:kBeaconPeripheralResponseParserGenericError
localizedDescription:@"CBPeripheralManagerの初期化に失敗しました。"];
return;
}
!
見つけてほしいビーコンのUUID
/* ビーコン領域を生成 */
NSUUID *uuid = [[NSUUID alloc] initWithUUIDString:BEACON_SERVICE_UUID];
self.beaconRegion = [[CLBeaconRegion alloc] initWithProximityUUID:uuid
major:12345
minor:67890
identifier:@"demo.Wibree.BeaconCentralResponseParser"];
if (! self.beaconRegion) {
/* ビーコン領域の初期化失敗 */
self.state = kBeaconPeripheralStateError;
self.error = [self _errorWithCode:kBeaconPeripheralResponseParserGenericError
localizedDescription:@"ビーコン領域の初期化に失敗しました。"];
self.peripheralManager = nil;
return;
}
!
/* 告知開始 */
NSDictionary
*dictionary = [self.beaconRegion peripheralDataWithMeasuredPower:nil];
[self.peripheralManager startAdvertising:dictionary];

20. iBeacon使用時の課題
個体の識別子はmajorとminorの番号。
ただし、Sample Codeでは取得できていない。