智能设备 和 app 通过 BLE通讯的两种模型
模型一：设备提供数据，app 展示数据； 比如小米手环
模型二：app提供数据，设备接收；
模型与corebluetooth的对应关系；
模型一：智能设备，对应 peripheral；app对应central
模型二：智能设备作为central ； app作为 peripheral
这里主要讨论模型一，这也是当前大多数手环设备和iOS 交互的方式；开发流程
1. 创建工程，导入CoreBluetooth.framework
2. 初始化 CBCentralManager 并准备扫描周围蓝牙设备
//初始化
theManager = [[CBCentralManager alloc]initWithDelegate:self queue:nil];
//初始化完成会调用如下代理，返回当前手机的蓝牙状态
//当前蓝牙主设备状态
-(void)centralManagerDidUpdateState:(CBCentralManager *)central{
if (central.state==CBCentralManagerStatePoweredOn) {
self.title = @"蓝牙已就绪";
self.connectBtn.enabled = YES;
}else
{
self.title = @"蓝牙未准备好";
[self.activeID stopAnimating];
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;
default:
break;
}
}
}
3. 当蓝牙状态一切正常时，这时可以开始搜索周边设备了，比如手环
//开始连接action
- (IBAction)startConnectAction:(id)sender {
if (theManager.state==CBCentralManagerStatePoweredOn) {
NSLog(@"主设备蓝牙状态正常，开始扫描外设...");
self.title = @"扫描小米手环...";
//nil表示扫描所有设备
[theManager scanForPeripheralsWithServices:nil options:nil];
[self.activeID startAnimating];
self.connectBtn.enabled = NO;
self.resultTextV.text = @"";
}
}
4. 在扫描到设备的代理里面，连接我们找到的智能设备
//扫描到设备会进入方法
-(void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI{
NSLog(@"扫描连接外设：%@ %@",peripheral.name,RSSI);
[central connectPeripheral:peripheral options:nil];
if ([peripheral.name hasSuffix:@"MI"]) {
thePerpher = peripheral;
[central stopScan];
[central connectPeripheral:peripheral options:nil];
self.title = @"发现小米手环，开始连接...";
self.resultTextV.text = [NSString stringWithFormat:@"发现手环：%@
名称：%@
",peripheral.identifier.UUIDString,peripheral.name];
}
}
5. 连接成功之后，去扫描设备的服务；扫描到服务之后，紧接着去扫描设备的特征；好比一个类提供的接口，只有知道这些，我们才能操作智能设备
//扫描到特征 -(void)peripheral:(CBPeripheral *)peripheral didDiscoverCharacteristicsForService:(CBService *)service error:(NSError *)error{ if (error) { NSLog(@"扫描外设的特征失败！%@->%@-> %@",peripheral.name,service.UUID, [error localizedDescription]); self.title = @"find characteristics error."; [self.activeID stopAnimating]; self.connectBtn.enabled = YES; return; } NSLog(@"扫描到外设服务特征有：%@->%@->%@",peripheral.name,service.UUID,service.characteristics); //获取Characteristic的值 for (CBCharacteristic *characteristic in service.characteristics){ { [peripheral setNotifyValue:YES forCharacteristic:characteristic]; //步数 if ([characteristic.UUID.UUIDString isEqualToString:kMI_STEP]) { [peripheral readValueForCharacteristic:characteristic]; } //电池电量 else if ([characteristic.UUID.UUIDString isEqualToString:kMI_BUTERY]) { [peripheral readValueForCharacteristic:characteristic]; } else if ([characteristic.UUID.UUIDString isEqualToString:kMI_SHAKE]) { //震动 theSakeCC = characteristic; } //设备信息 else if ([characteristic.UUID.UUIDString isEqualToString:kMI_DEVICE]) { [peripheral readValueForCharacteristic:characteristic]; } } } } //扫描到服务 -(void)peripheral:(CBPeripheral *)peripheral didDiscoverServices:(NSError *)error{ if (error) { NSLog(@"扫描外设服务出错：%@-> %@", peripheral.name, [error localizedDescription]); self.title = @"find services error."; [self.activeID stopAnimating]; self.connectBtn.enabled = YES; return; } NSLog(@"扫描到外设服务：%@ -> %@",peripheral.name,peripheral.services); for (CBService *service in peripheral.services) { [peripheral discoverCharacteristics:nil forService:service]; } NSLog(@"开始扫描外设服务的特征 %@...",peripheral.name); } #pragma mark 设备扫描与连接的代理 //连接到Peripherals-成功 - (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral { self.title = @"连接成功，扫描信息..."; NSLog(@"连接外设成功！%@",peripheral.name); [peripheral setDelegate:self]; [peripheral discoverServices:nil]; NSLog(@"开始扫描外设服务 %@...",peripheral.name); } //连接外设失败 -(void)centralManager:(CBCentralManager *)central didFailToConnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error { NSLog(@"连接到外设 失败！%@ %@",[peripheral name],[error localizedDescription]); [self.activeID stopAnimating]; self.title = @"连接失败"; self.connectBtn.enabled = YES; } //与外设断开连接 - (void)centralManager:(CBCentralManager *)central didDisconnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error{ NSLog(@"与外设备断开连接 %@: %@", [peripheral name], [error localizedDescription]); self.title = @"连接已断开"; self.connectBtn.enabled = YES; }
6. 当我们对设备发送一些指令时，会在如下代理里面响应到设备返回的数据
#pragma mark 设备信息处理 //扫描到具体的值 - (void)peripheral:(CBPeripheral *)peripheral didUpdateValueForCharacteristic:(CBCharacteristic *)characteristic error:(nullable NSError *)error { if (error) { NSLog(@"扫描外设的特征失败！%@-> %@",peripheral.name, [error localizedDescription]); self.title = @"find value error."; return; } NSLog(@"%@ %@",characteristic.UUID.UUIDString,characteristic.value); if ([characteristic.UUID.UUIDString isEqualToString:kMI_STEP]) { Byte *steBytes = (Byte *)characteristic.value.bytes; int steps = TCcbytesValueToInt(steBytes); NSLog(@"步数：%d",steps); self.resultTextV.text = [NSString stringWithFormat:@"%@步数：%d ",self.resultTextV.text,steps]; } else if ([characteristic.UUID.UUIDString isEqualToString:kMI_BUTERY]) { Byte *bufferBytes = (Byte *)characteristic.value.bytes; int buterys = TCcbytesValueToInt(bufferBytes)&0xff; NSLog(@"电池：%d%%",buterys); self.resultTextV.text = [NSString stringWithFormat:@"%@电量：%d%% ",self.resultTextV.text,buterys]; } else if ([characteristic.UUID.UUIDString isEqualToString:kMI_DEVICE]) { Byte *infoByts = (Byte *)characteristic.value.bytes; //这里解析infoByts得到设备信息 } [self.activeID stopAnimating]; self.connectBtn.enabled = YES; self.title = @"信息扫描完成"; }
7. 完整的代码工程；
https://github.com/cocoajin/BLE-miband