藍(lán)牙基礎(chǔ)

• MFI --- make for ipad ,iphone, itouch
• BLE --- buletouch low energy
• RSSI --- Received Signal Strength

<font color="blue">→_→ </font>developer.apple.com/CoreBluetooth

下面主要是用CoreBluetooth開發(fā)塑径。

中心（central）和外設(shè)（peripheral）

在CoreBluetooth框架下女坑，可以看成兩大模塊的通信：中心(central)和外設(shè)(peripheral)。

• central
  • 接收數(shù)據(jù)的一方晓勇，比如接收智能溫度計的數(shù)據(jù)顯示溫度的手機端堂飞。
• peripheral
  • 提供數(shù)據(jù)的一方。
  • 比如智能血壓計绑咱，智能溫度計绰筛。

服務(wù)(service)和特征(characteristic)

• service和characteristic是peripheral組織數(shù)據(jù)的一種方式。

• 一個peripheral可以有多個service描融， 每個service下可以有多個characteristic铝噩。
  

  <center>
  </center>
• characteristic下有具體的數(shù)據(jù)，比如智能燈下有兩個服務(wù)：溫度窿克、亮度骏庸。亮度服務(wù)下有多個特征：當(dāng)前亮度毛甲、10分鐘前亮度......

Central

使用步驟

1.導(dǎo)入CoreBluetooth模塊

@import CoreBluetooth;

2.遵從協(xié)議

@interface BluetoothController : NSViewController<CBCentralManagerDelegate, CBPeripheralDelegate>

3.創(chuàng)建Central和Peripheral（數(shù)組）

@property (nonatomic, strong) NSMutableArray *peripheralArray;
@property (nonatomic, strong) CBCentralManager *myCentralManager;

self.myCentralManager = [[CBCentralManager alloc] initWithDelegate:self queue:nil];
self.peripheralArray = [NSMutableArray array];

4.查詢藍(lán)牙狀態(tài)，可用的話具被，開始掃描

#pragma mark - CBCentralManagerDelegate methods

- (void)centralManagerDidUpdateState:(CBCentralManager *)central {
    NSDictionary *dic = [NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithBool:false], CBCentralManagerScanOptionAllowDuplicatesKey, nil];
    
    switch (central.state) {
        case CBCentralManagerStatePoweredOn:
            [self.myCentralManager scanForPeripheralsWithServices:nil options:dic];
            break;

        default:
            NSLog(@"Bluetooth is not working on the right state");
            break;
    }
}

5.發(fā)現(xiàn)Peripheral并連接

- (void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary<NSString *,id> *)advertisementData RSSI:(NSNumber *)RSSI {
    NSLog(@"Discovered %@", peripheral.name);
    [self.peripheralArray addObject:peripheral];
    if (self.targetPeripheral != peripheral) {
        self.targetPeripheral = peripheral;
        [self.myCentralManager connectPeripheral:peripheral options:[NSDictionary dictionaryWithObject:[NSNumber numberWithBool:YES] forKey:CBConnectPeripheralOptionNotifyOnDisconnectionKey]];
        peripheral.delegate = self; // 處理peripheral的事件
    }
}

這時運行程序玻募，打印如下

Discovered MyCBServer
Discovered John’s iPhone

上面的MyCBServer是我在iphone上運行的Bluetooth Server程序中的service名稱。John是我的名字一姿。

6.連接上peripheral, 并查詢服務(wù)

- (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral {
    NSLog(@"Connected to %@", peripheral.name);
    [peripheral discoverServices:nil]; //nil七咧，查詢所有服務(wù)
    //[peripheral discoverServices:@[[CBUUID UUIDWithString:kServiceUUID]]];//查詢指定服務(wù)
}

打印：

Connected to MyCBServer

7.peripheral查到服務(wù)

打印所有服務(wù)：

#pragma mark - CBPeripheralDelegate Methods

- (void)peripheral:(CBPeripheral *)peripheral didDiscoverServices:(NSError *)error {
    if (error) {
        NSLog(@"error in discovering serviecs: %@", [error localizedDescription]);
        return;
    }
    
    for (CBService *service in peripheral.services) {
        NSLog(@"service's uuid : %@", service.UUID);
    }
}

打印

service's uuid : Battery
service's uuid : Current Time
service's uuid : Device Information
service's uuid : Unknown (<c5ac0853 51224856 ac70a80e 990d1c15>)

上面的c5ac0853 51224856 ac70a80e 990d1c15就是iphone上運行的service UUID.

我手機上的Service和Characteristic的UUID分別為：

static NSString * const kServiceUUID = @"C5AC0853-5122-4856-AC70-A80E990D1C15";
static NSString * const kCharacteristicUUID = @"013AFE01-3E37-4E58-B6FD-DC4E67CF8F03";

上面的數(shù)字是在Mac上用uuidgen命令生成的叮叹。

UUID: Universally Unique Identifier

下面需要針對特定的service艾栋，讓peripheral去查它的characteristics。
這里即是針對kServiceUUID蛉顽，查它下面的特征蝗砾。

#pragma mark - CBPeripheralDelegate Methods

- (void)peripheral:(CBPeripheral *)peripheral didDiscoverServices:(NSError *)error {
    if (error) {
        NSLog(@"error in discovering serviecs: %@", [error localizedDescription]);
        return;
    }
    
    for (CBService *service in peripheral.services) {
//        NSLog(@"service's uuid : %@", service.UUID);
        if ([service.UUID isEqual:[CBUUID UUIDWithString: kServiceUUID]]) {
            [peripheral discoverCharacteristics:[NSArray arrayWithObject:[CBUUID UUIDWithString:kCharacteristicUUID]] forService:service];
        }
    }
}

8.peripheral查到特征

打印所有特征

- (void)peripheral:(CBPeripheral *)peripheral didDiscoverCharacteristicsForService:(CBService *)service error:(NSError *)error {
    if (error) {
        NSLog(@"error discovering characteristic : %@", [error localizedDescription]);
    }
    
    for (CBCharacteristic *characteristic in service.characteristics) {
        NSLog(@"characteristic uuid: %@", [characteristic UUID]);
    }
}

輸出：

characteristic uuid: Unknown (<013afe01 3e374e58 b6fddc4e 67cf8f03>)

試想這個場景：智能血壓計需要將某些數(shù)據(jù)即時更新給central。這里携冤，可以給指定的特征設(shè)置Notifiy, 設(shè)置以后悼粮，peripheral的特征值更新會及時通過delegate反饋過來。

- (void)peripheral:(CBPeripheral *)peripheral didDiscoverCharacteristicsForService:(CBService *)service error:(NSError *)error {
    if (error) {
        NSLog(@"error discovering characteristic : %@", [error localizedDescription]);
    }
    
    if ([service.UUID isEqual:[CBUUID UUIDWithString:kServiceUUID]]) {
        for (CBCharacteristic *characteristic in service.characteristics) {
//            NSLog(@"characteristic uuid: %@", [characteristic UUID]);
            if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:kCharacteristicUUID]]) {
                [peripheral setNotifyValue:YES forCharacteristic:characteristic];//訂閱特征
            }
        }
    }
}

9.peripheral說特征值有更新

上面setNotifyValue:YES函數(shù)設(shè)置了notify噪叙。那么這個特征值有更新的話矮锈，就會通過下面的函數(shù)告訴central

- (void)peripheral:(CBPeripheral *)peripheral didUpdateNotificationStateForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error {
    if (error) {
        NSLog(@"error notifying : %@", [error localizedDescription]);
        return;
    }

10.peripheral讀到數(shù)據(jù)

通過下面的代理方法獲取value：

- (void)peripheral:(CBPeripheral *)peripheral didUpdateValueForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error {
    if (error) {
        NSLog(@"error update value : %@", [error localizedDescription]);
        return;
    }
    
    NSString *value = [[NSString alloc] initWithData:characteristic.value encoding:NSUTF8StringEncoding];
    NSLog(@"Value: %@", value);
}

Peripheral

使用步驟

see also →_→ developer.apple.com/PeripheralRole

1.導(dǎo)入藍(lán)牙模塊

@import CoreBluetooth;

2.遵從CBPeripheralManagerDelegate協(xié)議

@interface ViewController : UIViewController<CBPeripheralManagerDelegate>

3.創(chuàng)建myPeripheralManager

@property (nonatomic, strong) CBPeripheralManager *myPeripheralManager;

self.myPeripheralManager = [[CBPeripheralManager alloc] initWithDelegate:self queue:nil];

4.查詢藍(lán)牙狀態(tài), 可用的話添加服務(wù)

#pragma mark - Custom methods

- (void)addService {
    CBMutableService *service = [[CBMutableService alloc] initWithType:[CBUUID UUIDWithString:kServiceUUID] primary:YES];//primary
    CBMutableCharacteristic *characteristic = [[CBMutableCharacteristic alloc] initWithType:[CBUUID UUIDWithString:kCharacteristicUUID] properties:CBCharacteristicPropertyNotify value:nil permissions:CBAttributePermissionsReadable];
    self.myCharacteristic = characteristic;
    [service setCharacteristics:@[characteristic]];
    
    [self.myPeripheralManager addService:service];
}

#pragma mark - CBPeripheralManagerDelegate methods

- (void)peripheralManagerDidUpdateState:(CBPeripheralManager *)peripheral {
    switch (peripheral.state) {
        case CBPeripheralManagerStatePoweredOn:
            [self addService];
            break;
            
        default:
            NSLog(@"Peripheral Manager is not working on the right state");
            break;
    }
}

5.服務(wù)添加成功霉翔，開始廣告

- (void)peripheralManager:(CBPeripheralManager *)peripheral didAddService:(CBService *)service error:(NSError *)error {
    if (error) {
        NSLog(@"Error publishing service: %@", [error localizedDescription]);
        return;
    }
    
    [self.myPeripheralManager startAdvertising:@{CBAdvertisementDataLocalNameKey:@"MyCBServer", CBAdvertisementDataServiceUUIDsKey: [CBUUID UUIDWithString:kServiceUUID]}];
}

6.廣告成功

- (void)peripheralManagerDidStartAdvertising:(CBPeripheralManager *)peripheral error:(NSError *)error {
    if (error) {
        NSLog(@"error advertising : %@", [error localizedDescription]);
        self.showLabel.text = [NSString stringWithFormat:@"error advertising: %@", [error localizedDescription]];
        return;
    }
    
    self.showLabel.text = @"start advertising";
    
}

7.更新特征值

<center>

</center>
添加兩個button睁蕾，用來改變特征值

@property (nonatomic, assign) NSInteger count;

- (IBAction)MinusButtonClicked:(id)sender {
    if ([self.myPeripheralManager state] != CBPeripheralManagerStatePoweredOn) {
        return;
    }
    --(self.count);
    NSData *data = [[NSString stringWithFormat:@"count is now %ld", (long)self.count] dataUsingEncoding:NSUTF8StringEncoding];
    [self.myPeripheralManager updateValue:data forCharacteristic:self.myCharacteristic onSubscribedCentrals:self.centrayArray];
}
- (IBAction)AddButtonClicked:(id)sender {
    if ([self.myPeripheralManager state] != CBPeripheralManagerStatePoweredOn) {
        return;
    }
    ++(self.count);
    NSData *data = [[NSString stringWithFormat:@"count is now %ld", (long)self.count] dataUsingEncoding:NSUTF8StringEncoding];
    [self.myPeripheralManager updateValue:data forCharacteristic:self.myCharacteristic onSubscribedCentrals:self.centrayArray];
}

點擊button，central輸出：

Value: count is now -2
Value: count is now -1
Value: count is now 0
Value: count is now 1

資源

完整代碼已上傳到 →_→ github, 歡迎下載使用债朵。