简介
开发使用的框架是CoreBluetooth框架,CoreBluetooth是基于BLE4.0的标准的。什么是BLE呢?全称是 buletouch low energy,就是蓝牙低能耗技术。在没有开发蓝牙4.0技术的时候,iOS设备要想开发一个根硬件通讯功能的话,必须通过苹果的mfi认证,否则是不被允许与其他硬件进行连接的,mfi全称是 make for ipad ,iphone, itouch ,是专门为苹果设备制作的设备。注意,iOS设备支持BLE4.0是从iPhone4s开始的(不包括iPhone4s)。
业务逻辑、角色、内容
业务角色
主要分为两个部分
(1)central:中央设备,又叫做中央角色,搜索可以连接的外设,然后请求连接,请求通过后就可以交换数据了。使用的是外围设备的数据,可以写入数据到外围设备
(2)peripheral:外围设备,(下边我都称为外设)又叫做周边设备,用来广播数据的设备,告诉外部这有数据,并且说明了能提供的服务,外围设备可以发送数据到中央设备
数据结构:外围设备会发送服务(Service),一个服务里面又包含多个特征,特征就是具体键值对,提供数据的地方。每个特征属性分为这么几种:读,写,通知这么几种方式。同时,一个外围设备在广播服务的时候,可以同时发送多个服务。
工作流程
(1)外设发布服务
(2)中央搜索外设
(3)连接外设
(4)获得服务以及每个服务的特征
(5)获得特征中的值
方法属性介绍
CBCentralManager是中央设备的管理者,一个项目中最好只有一个中央设备管理者,因此在项目中尽量用单例去初始化。
@interface ViewController : UIViewController
@interface ViewController ()
{
CBCentralManager *manager; //系统蓝牙设备管理对象,可以把他理解为主设备,通过他,可以去扫描和链接外设
NSMutableArray *peripherals; //用于保存被发现设备
}
具体实现步骤代码:
1 导入CoreBluetooth头文件,建立主设备管理类,设置主设备委托
#import
@interface ViewController : UIViewController
@interface ViewController (){
CBCentralManager *manager; //系统蓝牙设备管理对象,可以把他理解为主设备,通过他,可以去扫描和链接外设
NSMutableArray *peripherals; //用于保存被发现设备
} - (void)viewDidLoad { [super viewDidLoad];
/* 设置主设备的委托,CBCentralManagerDelegate 必须实现的:
//主设备状态改变的委托,在初始化CBCentralManager的适合会打开设备,只有当设备正确打开后才能使用 其他选择实现的委托中比较重要的
- (void)centralManagerDidUpdateState:(CBCentralManager *)central;
//找到外设的委托
- (void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI;
//连接外设成功的委托
- (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral;
//外设连接失败的委托
- (void)centralManager:(CBCentralManager *)central didFailToConnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error;
//断开外设的委托
- (void)centralManager:(CBCentralManager *)central didDisconnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error;
*/
//初始化并设置委托和线程队列,最好一个线程的参数可以为nil,默认会就main线程 manager = [[CBCentralManager alloc]initWithDelegate:self queue:dispatch_get_main_queue()];
2 扫描外设(discover),扫描外设的方法我们放在centralManager成功打开的委托中,因为只有设备成功打开,才能开始扫描,否则会报错
-(void)centralManagerDidUpdateState:(CBCentralManager *)central{ switch (central.state) {
case CBCentralManagerStateUnknown:
NSLog(@">>>CBCentralManagerStateUnknown");
break;
case CBCentralManagerStateResetting:
NSLog(@">>>CBCentralManagerStateResetting");
break;
case CBCentralManagerStateUnsupported:
NSLog(@">>>CBCentralManagerStateUnsupported");
break;
case CBCentralManagerStateUnauthorized:
NSLog(@">>>CBCentralManagerStateUnauthorized");
break;
case CBCentralManagerStatePoweredOff:
NSLog(@">>>CBCentralManagerStatePoweredOff");
break;
case CBCentralManagerStatePoweredOn:
NSLog(@">>>CBCentralManagerStatePoweredOn"); //开始扫描周围的外设
/*
第一个参数nil就是扫描周围所有的外设,扫描到外设后会进入
- (void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI;
*/
[manager scanForPeripheralsWithServices:nil options:nil];
break;
default: break;
} }
//扫描到设备会进入方法
-(void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI{
NSLog(@"当扫描到设备:%@",peripheral.name); //接下来可以连接设备
}
3 连接外设(connect)
//扫描到设备会进入方法
-(void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI{
//接下连接我们的测试设备,如果你没有设备,可以下载一个app叫lightbule的app去模拟一个设备
//这里自己去设置下连接规则,我设置的是P开头的设备
if ([peripheral.name hasPrefix:@"P"])
{
/*
一个主设备最多能连7个外设,每个外设最多只能给一个主设备连接,连接成功,失败,断开会进入各自的委托
//连接外设成功的委托
- (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral;
//外设连接失败的委托
- (void)centralManager:(CBCentralManager *)central didFailToConnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error;
//断开外设的委托
- (void)centralManager:(CBCentralManager *)central didDisconnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error;
*/
//找到的设备必须持有它,否则CBCentralManager中也不会保存peripheral,那么CBPeripheralDelegate中的方法也不会被调用!! [peripherals addObject:peripheral];
//连接设备
[manager connectPeripheral:peripheral options:nil];
}
}
//连接到Peripherals-成功
- (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral {
NSLog(@">>>连接到名称为(%@)的设备-成功",peripheral.name);
}
//连接到Peripherals-失败
-(void)centralManager:(CBCentralManager *)central didFailToConnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error {
NSLog(@">>>连接到名称为(%@)的设备-失败,原因:%@",[peripheral name],[error localizedDescription]);
}
//Peripherals断开连接
- (void)centralManager:(CBCentralManager *)central didDisconnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error{
NSLog(@">>>外设连接断开连接 %@: %@\n", [peripheral name], [error localizedDescription]);
}
4扫描外设中的服务和特征(discover)
设备连接成功后,就可以扫描设备的服务了,同样是通过委托形式,扫描到结果后会进入委托方法。但是这个委托已经不再是主设备的委托(CBCentralManagerDelegate),而是外设的委托(CBPeripheralDelegate),这个委托包含了主设备与外设交互的许多 回叫方法,包括获取services,获取characteristics,获取characteristics的值,获取characteristics的Descriptor,和Descriptor的值,写数据,读rssi,用通知的方式订阅数据等等。
获取外设的services
//连接到Peripherals-成功
- (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral {
NSLog(@">>>连接到名称为(%@)的设备-成功",peripheral.name);
//设置的peripheral委托CBPeripheralDelegate
//@interface ViewController : UIViewController [peripheral setDelegate:self];
//扫描外设Services,成功后会进入方法:
-(void)peripheral:(CBPeripheral *)peripheral didDiscoverServices:(NSError *)error{ [peripheral discoverServices:nil];
}
//扫描到Services
-(void)peripheral:(CBPeripheral *)peripheral didDiscoverServices:(NSError *)error{
// NSLog(@">>>扫描到服务:%@",peripheral.services);
if (error) {
NSLog(@">>>Discovered services for %@ with error: %@", peripheral.name, [error localizedDescription]);
return;
}
for (CBService *service in peripheral.services) { NSLog(@"%@",service.UUID);
//扫描每个service的Characteristics,扫描到后会进入方法:
-(void)peripheral:(CBPeripheral *)peripheral didDiscoverCharacteristicsForService:(CBService *)service error:(NSError *)error [peripheral discoverCharacteristics:nil forService:service];
}
}
获取外设的Characteristics,获取Characteristics的值,获取Characteristics的Descriptor和Descriptor的值
//扫描到Characteristics
-(void)peripheral:(CBPeripheral *)peripheral didDiscoverCharacteristicsForService:(CBService *)service error:(NSError *)error{
if (error)
{
NSLog(@"error Discovered characteristics for %@ with error: %@", service.UUID, [error localizedDescription]);
return;
}
for (CBCharacteristic *characteristic in service.characteristics)
{
NSLog(@"service:%@ 的 Characteristic: %@",service.UUID,characteristic.UUID);
}
//获取Characteristic的值,读到数据会进入方法:
-(void)peripheral:(CBPeripheral *)peripheral didUpdateValueForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error
for (CBCharacteristic *characteristic in service.characteristics){
{
[peripheral readValueForCharacteristic:characteristic];
}
}
//搜索Characteristic的Descriptors,读到数据会进入方法:
-(void)peripheral:(CBPeripheral *)peripheral didDiscoverDescriptorsForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error
for (CBCharacteristic *characteristic in service.characteristics){
[peripheral discoverDescriptorsForCharacteristic:characteristic];
}
}
//获取的charateristic的值
-(void)peripheral:(CBPeripheral *)peripheral didUpdateValueForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error{
//打印出characteristic的UUID和值
//!注意,value的类型是NSData,具体开发时,会根据外设协议制定的方式去解析数据
NSLog(@"characteristic uuid:%@ value:%@",characteristic.UUID,characteristic.value);
}
//搜索到Characteristic的Descriptors
-(void)peripheral:(CBPeripheral *)peripheral didDiscoverDescriptorsForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error{
//打印出Characteristic和他的Descriptors
NSLog(@"characteristic uuid:%@",characteristic.UUID);
for (CBDescriptor *d in characteristic.descriptors) {
NSLog(@"Descriptor uuid:%@",d.UUID);
}
}
//获取到Descriptors的值
-(void)peripheral:(CBPeripheral *)peripheral didUpdateValueForDescriptor:(CBDescriptor *)descriptor error:(NSError *)error{
//打印出DescriptorsUUID 和value
//这个descriptor都是对于characteristic的描述,一般都是字符串,所以这里我们转换成字符串去解析
NSLog(@"characteristic uuid:%@ value:%@",[NSString stringWithFormat:@"%@",descriptor.UUID],descriptor.value);
}
5、把数据写到Characteristic中
//写数据
-(void)writeCharacteristic:(CBPeripheral *)peripheral characteristic:(CBCharacteristic *)characteristic value:(NSData *)value{
//打印出 characteristic 的权限,可以看到有很多种,这是一个NS_OPTIONS,就是可以同时用于好几个值,常见的有read,write,notify,indicate,知知道这几个基本就够用了,前连个是读写权限,后两个都是通知,两种不同的通知方式。
/*
typedef NS_OPTIONS(NSUInteger, CBCharacteristicProperties) { CBCharacteristicPropertyBroadcast = 0x01, CBCharacteristicPropertyRead = 0x02, CBCharacteristicPropertyWriteWithoutResponse = 0x04, CBCharacteristicPropertyWrite = 0x08, CBCharacteristicPropertyNotify = 0x10, CBCharacteristicPropertyIndicate = 0x20, CBCharacteristicPropertyAuthenticatedSignedWrites = 0x40, CBCharacteristicPropertyExtendedProperties = 0x80, CBCharacteristicPropertyNotifyEncryptionRequired NS_ENUM_AVAILABLE(NA, 6_0) = 0x100, CBCharacteristicPropertyIndicateEncryptionRequired NS_ENUM_AVAILABLE(NA, 6_0) = 0x200 };
*/
NSLog(@"%lu", (unsigned long)characteristic.properties);
//只有 characteristic.properties 有write的权限才可以写 if(characteristic.properties & CBCharacteristicPropertyWrite){
/*
最好一个type参数可以为CBCharacteristicWriteWithResponse或type:CBCharacteristicWriteWithResponse,区别是是否会有反馈
*/
[peripheral writeValue:value forCharacteristic:characteristic type:CBCharacteristicWriteWithResponse];
}else{
NSLog(@"该字段不可写!");
}
}
6 订阅Characteristic的通知
//设置通知
-(void)notifyCharacteristic:(CBPeripheral *)peripheral characteristic:(CBCharacteristic *)characteristic{
//设置通知,数据通知会进入:didUpdateValueForCharacteristic方法 [peripheral setNotifyValue:YES forCharacteristic:characteristic];
}
//取消通知
-(void)cancelNotifyCharacteristic:(CBPeripheral *)peripheral characteristic:(CBCharacteristic *)characteristic{ [peripheral setNotifyValue:NO forCharacteristic:characteristic];
}
7 断开连接(disconnect)
//停止扫描并断开连接
-(void)disconnectPeripheral:(CBCentralManager *)centralManager peripheral:(CBPeripheral *)peripheral{
//停止扫描
[centralManager stopScan];
//断开连接
[centralManager cancelPeripheralConnection:peripheral]; }
8 模拟器蓝牙调试,慎用,最好还是用真机去调试。