ios蓝牙开发（三）app作为外设被连接的实现

再上一节说了app作为central连接peripheral的情况，这一节介绍如何使用app发布一个peripheral，给其他的central连接

还是这张图，central模式用的都是左边的类，而peripheral模式用的是右边的类

peripheral模式的流程

1. 打开peripheralManager，设置peripheralManager的委托

2. 创建characteristics，characteristics的description 创建service，把characteristics添加到service中，再把service添加到peripheralManager中

3. 开启广播advertising

4. 对central的操作进行响应

    - 4.1 读characteristics请求

    - 4.2 写characteristics请求

    - 4.4 订阅和取消订阅characteristics

准备环境

  1 xcode

  2 开发证书和手机（蓝牙程序需要使用使用真机调试，使用模拟器也可以调试，但是方法很蛋疼，我会放在最后说），如果不行可以使用osx程序调试

  3 蓝牙外设

实现步骤

1. 打开peripheralManager，设置peripheralManager的委托

设置当前ViewController实现CBPeripheralManagerDelegate委托

    @interface BePeripheralViewController : UIViewController<CBPeripheralManagerDelegate>

初始化peripheralManager

     /*

     和CBCentralManager类似，蓝牙设备打开需要一定时间，打开成功后会进入委托方法

     - (void)peripheralManagerDidUpdateState:(CBPeripheralManager *)peripheral;

     模拟器永远也不会得CBPeripheralManagerStatePoweredOn状态

     */

    peripheralManager = [[CBPeripheralManager alloc]initWithDelegate:self queue:nil];

2. 创建characteristics，characteristics的description ，创建service，把characteristics添加到service中，再把service添加到peripheralManager中

在委托方法 - (void)peripheralManagerDidUpdateState:(CBPeripheralManager *)peripheral中，当peripheral成功打开后，才可以配置service和characteristics。这里创建的service和chara对象是CBMutableCharacteristic和CBMutableService。他们的区别就像NSArray和NSMutableArray区别类似。我们先创建characteristics和description，description是characteristics的描述，描述分很多种，这里不细说了，常用的就是CBUUIDCharacteristicUserDescriptionString。

//peripheralManager状态改变

- (void)peripheralManagerDidUpdateState:(CBPeripheralManager *)peripheral{

    switch (peripheral.state) {

            //在这里判断蓝牙设别的状态  当开启了则可调用  setUp方法(自定义)

        case CBPeripheralManagerStatePoweredOn:

            NSLog(@"powered on");

            [info setText:[NSString stringWithFormat:@"设备名%@已经打开，可以使用center进行连接",LocalNameKey]];

            [self setUp];

            break;

        case CBPeripheralManagerStatePoweredOff:

            NSLog(@"powered off");

            [info setText:@"powered off"];

            break;

        default:

            break;

    }

}

 //配置bluetooch的

 -(void)setUp{

        //characteristics字段描述

        CBUUID *CBUUIDCharacteristicUserDescriptionStringUUID = [CBUUID UUIDWithString:CBUUIDCharacteristicUserDescriptionString];

        /*

         可以通知的Characteristic

         properties：CBCharacteristicPropertyNotify

         permissions CBAttributePermissionsReadable

         */

        CBMutableCharacteristic *notiyCharacteristic = [[CBMutableCharacteristic alloc]initWithType:[CBUUID UUIDWithString:notiyCharacteristicUUID] properties:CBCharacteristicPropertyNotify value:nil permissions:CBAttributePermissionsReadable];

        /*

         可读写的characteristics

         properties：CBCharacteristicPropertyWrite | CBCharacteristicPropertyRead

         permissions CBAttributePermissionsReadable | CBAttributePermissionsWriteable

         */

        CBMutableCharacteristic *readwriteCharacteristic = [[CBMutableCharacteristic alloc]initWithType:[CBUUID UUIDWithString:readwriteCharacteristicUUID] properties:CBCharacteristicPropertyWrite | CBCharacteristicPropertyRead value:nil permissions:CBAttributePermissionsReadable | CBAttributePermissionsWriteable];

        //设置description

        CBMutableDescriptor *readwriteCharacteristicDescription1 = [[CBMutableDescriptor alloc]initWithType: CBUUIDCharacteristicUserDescriptionStringUUID value:@"name"];

        [readwriteCharacteristic setDescriptors:@[readwriteCharacteristicDescription1]];

        /*

         只读的Characteristic

         properties：CBCharacteristicPropertyRead

         permissions CBAttributePermissionsReadable

         */

        CBMutableCharacteristic *readCharacteristic = [[CBMutableCharacteristic alloc]initWithType:[CBUUID UUIDWithString:readCharacteristicUUID] properties:CBCharacteristicPropertyRead value:nil permissions:CBAttributePermissionsReadable];

        //service1初始化并加入两个characteristics

        CBMutableService *service1 = [[CBMutableService alloc]initWithType:[CBUUID UUIDWithString:ServiceUUID1] primary:YES];

        [service1 setCharacteristics:@[notiyCharacteristic,readwriteCharacteristic]];

        //service2初始化并加入一个characteristics

        CBMutableService *service2 = [[CBMutableService alloc]initWithType:[CBUUID UUIDWithString:ServiceUUID2] primary:YES];

        [service2 setCharacteristics:@[readCharacteristic]];

        //添加后就会调用代理的- (void)peripheralManager:(CBPeripheralManager *)peripheral didAddService:(CBService *)service error:(NSError *)error

        [peripheralManager addService:service1];

        [peripheralManager addService:service2];

 }

3. 开启广播advertising

//perihpheral添加了service

- (void)peripheralManager:(CBPeripheralManager *)peripheral didAddService:(CBService *)service error:(NSError *)error{

    if (error == nil) {

        serviceNum++;

    }

    //因为我们添加了2个服务，所以想两次都添加完成后才去发送广播

    if (serviceNum==2) {

        //添加服务后可以在此向外界发出通告 调用完这个方法后会调用代理的

        //(void)peripheralManagerDidStartAdvertising:(CBPeripheralManager *)peripheral error:(NSError *)error

        [peripheralManager startAdvertising:@{

                                              CBAdvertisementDataServiceUUIDsKey : @[[CBUUID UUIDWithString:ServiceUUID1],[CBUUID UUIDWithString:ServiceUUID2]],

                                              CBAdvertisementDataLocalNameKey : LocalNameKey

                                             }

         ];

    }

}

//peripheral开始发送advertising

- (void)peripheralManagerDidStartAdvertising:(CBPeripheralManager *)peripheral error:(NSError *)error{

    NSLog(@"in peripheralManagerDidStartAdvertisiong");

}

4. 对central的操作进行响应

- 4.1 读characteristics请求

- 4.2 写characteristics请求

- 4.3 订阅和取消订阅characteristics

//订阅characteristics

-(void)peripheralManager:(CBPeripheralManager *)peripheral central:(CBCentral *)central didSubscribeToCharacteristic:(CBCharacteristic *)characteristic{

    NSLog(@"订阅了 %@的数据",characteristic.UUID);

    //每秒执行一次给主设备发送一个当前时间的秒数

    timer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(sendData:) userInfo:characteristic  repeats:YES];

}

//取消订阅characteristics

-(void)peripheralManager:(CBPeripheralManager *)peripheral central:(CBCentral *)central didUnsubscribeFromCharacteristic:(CBCharacteristic *)characteristic{

    NSLog(@"取消订阅 %@的数据",characteristic.UUID);

    //取消回应

    [timer invalidate];

}

//发送数据，发送当前时间的秒数

-(BOOL)sendData:(NSTimer *)t {

    CBMutableCharacteristic *characteristic = t.userInfo;

    NSDateFormatter *dft = [[NSDateFormatter alloc]init];

    [dft setDateFormat:@"ss"];

    NSLog(@"%@",[dft stringFromDate:[NSDate date]]);

    //执行回应Central通知数据

    return  [peripheralManager updateValue:[[dft stringFromDate:[NSDate date]] dataUsingEncoding:NSUTF8StringEncoding] forCharacteristic:(CBMutableCharacteristic *)characteristic onSubscribedCentrals:nil];

}

//读characteristics请求

- (void)peripheralManager:(CBPeripheralManager *)peripheral didReceiveReadRequest:(CBATTRequest *)request{

    NSLog(@"didReceiveReadRequest");

    //判断是否有读数据的权限

    if (request.characteristic.properties & CBCharacteristicPropertyRead) {

        NSData *data = request.characteristic.value;

        [request setValue:data];

        //对请求作出成功响应

        [peripheralManager respondToRequest:request withResult:CBATTErrorSuccess];

    }else{

        [peripheralManager respondToRequest:request withResult:CBATTErrorWriteNotPermitted];

    }

}

//写characteristics请求

- (void)peripheralManager:(CBPeripheralManager *)peripheral didReceiveWriteRequests:(NSArray *)requests{

    NSLog(@"didReceiveWriteRequests");

    CBATTRequest *request = requests[0];

    //判断是否有写数据的权限

    if (request.characteristic.properties & CBCharacteristicPropertyWrite) {

        //需要转换成CBMutableCharacteristic对象才能进行写值

        CBMutableCharacteristic *c =(CBMutableCharacteristic *)request.characteristic;

        c.value = request.value;

        [peripheralManager respondToRequest:request withResult:CBATTErrorSuccess];

    }else{

        [peripheralManager respondToRequest:request withResult:CBATTErrorWriteNotPermitted];

    }

}

代码下载:

我博客中大部分示例代码都上传到了github，地址是：https://github.com/coolnameismy/demo，点击跳转代码下载地址

本文代码存放目录是BleDemo

巴特西