圖片發(fā)自簡(jiǎn)書App

首先先介紹一下藍(lán)牙開發(fā)的模式：

1. 藍(lán)牙中心模式
2. 藍(lán)牙外設(shè)模式
   一.藍(lán)牙中心模式

1.創(chuàng)建 CBCentralManager 中心對(duì)象
2.central掃描外設(shè) discover
3.central連接外設(shè) connect

4. 掃描外設(shè)中的服務(wù)和特征discover
   4.1、獲取外設(shè)的 services：

執(zhí)行：discoverServices
成功后執(zhí)行：peripheral:didDiscoverServices
委托方法
4.2、獲取外設(shè)的 Characteristics，獲取 Characteristics 的值：

執(zhí)行：discoverCharacteristics:forService
成功后執(zhí)行：peripheral:didDiscoverCharacteristicsForService:error
委托方法
4.3、獲取外設(shè)的Characteristics 的 Descriptor 和 Descriptor 的值：

讀特征值：readValueForCharacteristic
讀到后進(jìn)入：didUpdateValueForCharacteristic:error委托方法
搜索 Characteristic：discoverDescriptorsForCharacteristic
搜到后進(jìn)入：didDiscoverDescriptorsForCharacteristic:error委托方法
獲取到 Descriptors 的值：peripheral:didUpdateValueForDescriptor:error
Descriptors 是對(duì) characteristic 的描述，一般是字符串
4.4、把數(shù)據(jù)寫到 Characteristic：writeCharacteristic:charactericstic:value
4.5、讀 RSSI，用通知的方式訂閱數(shù)據(jù)等。
5、與外設(shè)做數(shù)據(jù)交互 explored interact
6、訂閱 Characteristic 的通知：notifyCharacteristic:characteristic
取消通知：cancelNotifyCharacteristic:characteristic
7、斷開連接 disconnect：disconnnectPeripheral:peripheral

圖片發(fā)自簡(jiǎn)書App

二.藍(lán)牙外設(shè)模式流程

1.創(chuàng)建一個(gè) Peripheral 管理對(duì)象

peripheralManager = [[CBPeripheralManager alloc] initWithDelegate:self queue:nil];
藍(lán)牙設(shè)備打開成功后會(huì)進(jìn)入委托方法：peripheralManagerDidUpdateState:

2. 本地 Peripheral 設(shè)置服務(wù)、特性、描述、權(quán)限等。

創(chuàng)建 Characteristics 及其 description，創(chuàng)建 service，把 characteristics 添加到 service 中，再把 service 添加到 peripheralManager 中。

3. Peripheral 發(fā)送廣播 advertising：peripheralManagerDidStartAdvertising:error

Peripheral 添加service：peripheralManager:didAddService:error

4. 對(duì) central 的操作進(jìn)行響應(yīng)

讀 characteristics 請(qǐng)求：peripheralManager:didReceiveReadQuest:
寫characteristics 請(qǐng)求：peripheralManager:didReceiveWriteRequests:
訂閱特征：peripheralManager:central:didSubscribeToCharacteristic:
取消訂閱peripheralManager:central:didUnsubscribeFromCharacteristic:
一些基本屬性:

RSSI：信號(hào)強(qiáng)弱值，防丟器會(huì)用到。
UUID：唯一標(biāo)識(shí)符，用于區(qū)分設(shè)備
service UUID：服務(wù)，一個(gè) Server 會(huì)包含多個(gè)characteristic，用 UUID 來區(qū)分。
characteristic：特征，用 UUID 來區(qū)分
了解了以上流程：由于蘋果的封閉生態(tài)，之前對(duì)藍(lán)牙的限制比較嚴(yán)格，如果要和 iOS 設(shè)備通信，必須是經(jīng)過了 MFI 認(rèn)證的芯片才可以；藍(lán)牙4.0低功耗模式的到來，蘋果也對(duì)藍(lán)牙放開了一些限制。所以目前針對(duì) iOS 的藍(lán)牙編程主要就是針對(duì)藍(lán)牙4.0以上的低功耗藍(lán)牙，也就是 BLE 模式。
BLE 模式的特點(diǎn)：

功耗低。
連接速度很快，連接距離遠(yuǎn)（100米）。
相應(yīng)的傳輸數(shù)據(jù)量小，比傳統(tǒng)藍(lán)牙傳輸?shù)男『芏啵瑩?jù)說單次發(fā)送也就20字節(jié)。

BLE 模式并不適合用來做較大數(shù)據(jù)量的傳輸使用
Bluetooth.h

@property(nonatomic,strong) CBCentralManager *centralManager;
@property(nonatomic,strong) CBPeripheral *peripheral;
@property(nonatomic,strong) CBCharacteristic *characteristic;
@property(nonatomic,strong) NSMutableArray *peripheralArray;

• (void)initBluetooth; //初始化藍(lán)牙
• (void)scanBluetooth; //掃描藍(lán)牙
• (void)stopScanBluetooth; //停止掃描
• (void)connectPeripheral:(CBPeripheral *)peripheral; //連接藍(lán)牙
• (void)disConnectPeripheral:(CBPeripheral *)peripheral; //取消連接藍(lán)牙
• (void)sendData:(NSData *)data; //向掃描到的藍(lán)牙Characteristic 發(fā)送數(shù)據(jù)

Bluetooth.m

// 初始化藍(lán)牙

• (void)initBluetooth
  {
  _centralManager = [[CBCentralManager alloc] initWithDelegate:self queue:nil];//創(chuàng)建CBCentralManager對(duì)象
  _peripheralArray = [[NSMutableArray alloc] init];
  }

//掃描藍(lán)牙

• (void)scanBluetooth
  {
  NSLog(@"BluetoothBase scanBluetooth");
  //CBCentralManagerScanOptionAllowDuplicatesKey值為 No，表示不重復(fù)掃描已發(fā)現(xiàn)的設(shè)備
  NSDictionary *optionDic = [NSDictionary dictionaryWithObject:[NSNumber numberWithBool:NO] forKey:CBCentralManagerScanOptionAllowDuplicatesKey];
  [_centralManager scanForPeripheralsWithServices:nil options:optionDic];//如果你將第一個(gè)參數(shù)設(shè)置為nil，Central Manager就會(huì)開始尋找所有的服務(wù)。
  }
  //停止掃描藍(lán)牙

• (void)stopScanBluetooth
  {
  [self.centralManager stopScan];
  NSLog(@"BluetoothBase stopScanBluetooth，已經(jīng)連接外設(shè)停止掃描或者手動(dòng)停止掃描");
  }
  //連接藍(lán)牙

• (void)connectPeripheral:(CBPeripheral *)peripheral
  {
  [self.centralManager connectPeripheral:peripheral options:nil];
  self.peripheral = peripheral;
  peripheral.delegate = self; //連接時(shí)設(shè)置代理
  }
  //取消連接藍(lán)牙

• (void)disConnectPeripheral:(CBPeripheral *)peripheral
  {
  [_centralManager cancelPeripheralConnection:peripheral];
  }
  //如果發(fā)送的數(shù)據(jù)過大，就需要做分包處理了。至于傳輸?shù)淖畲笞止?jié)數(shù)是多大，就需要和硬件工程師討論了。pl @PlatoJobs
  //向藍(lán)牙寫入數(shù)據(jù)

• (void)sendData:(NSData *)data
  {
  [self initBluetoothDispatch];

  if (_characteristic.properties & CBCharacteristicPropertyWrite){
  [_peripheral writeValue:data forCharacteristic:_characteristic type:CBCharacteristicWriteWithResponse];
  NSLog(@"BluetoothBase writeDataToCharacteristic:%@",[_characteristic.UUID UUIDString]);
  }else{
  NSLog(@"沒有發(fā)現(xiàn)可以寫入的characteristic");
  }
  }
  藍(lán)牙的一些代理方法(CBCentralManagerDelegate)：

//centralManager已經(jīng)更新狀態(tài)

• (void)centralManagerDidUpdateState:(CBCentralManager *)central
  {
  NSLog(@"centralManagerDidUpdateState:%ld",(long)central.state);
  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:
  [self scanBluetooth]; //很重要，當(dāng)藍(lán)牙處于打開狀態(tài)，開始掃描。
  break;
  default:
  NSLog(@"藍(lán)牙未工作在正確狀態(tài)");
  break;
  }
  }

//centralManager已經(jīng)發(fā)現(xiàn)外設(shè)

//掃描到外設(shè)，停止掃描，連接設(shè)備(每掃描到一個(gè)外設(shè)都會(huì)調(diào)用一次這個(gè)函數(shù)，若要展示搜索到的藍(lán)牙，可以逐一保存 peripheral 并展示)

• (void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary<NSString *,id> *)advertisementData RSSI:(NSNumber *)RSSI
  {
  [_peripheralArray addObject:peripheral]; //保存用于連接的 peripheral
  [PRTBluetoothModel share].peripheralArray = _peripheralArray;

  [[NSNotificationCenter defaultCenter] postNotificationName:@"PRTBluetoothScanUpdatePeripheralList" object:nil];
  }
  //已經(jīng)連接外設(shè)
  //連接外設(shè)成功，掃描外設(shè)中的服務(wù)和特征

• (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral
  {
  [PRTDispatchModel share].currentDispatchMode = PRTPrinterModeBle; //將藍(lán)牙模式保存到當(dāng)前傳輸模式。

  NSLog(@"didConnectPeripheral:%@",peripheral.name);
  [[NSNotificationCenter defaultCenter] postNotificationName:@"PRTBluetoothScanDidConnectPeripheral" object:nil];

  [self stopScanBluetooth]; //連接成功后停止掃描

  [self.peripheral setDelegate:self];

  //數(shù)組中存放兩個(gè)服務(wù)的 UUID
  NSMutableArray *uuidArray = [[NSMutableArray alloc] initWithObjects:[CBUUID UUIDWithString:UUID_String_DeviceInfo_Service], [CBUUID UUIDWithString:UUIDSTR_ISSC_PROPRIETARY_SERVICE], nil];

  [peripheral discoverServices:uuidArray];//發(fā)現(xiàn)服務(wù)，成功后執(zhí)行：peripheral:didDiscoverServices委托方法
  }
  //連接外設(shè)失敗

• (void)centralManager:(CBCentralManager *)central didFailToConnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error
  {
  NSLog(@"didFailToConnectPeripheral:%@",error);
  }
  //已經(jīng)發(fā)現(xiàn)服務(wù)

• (void)peripheral:(CBPeripheral *)peripheral didDiscoverServices:(NSError *)error
  {
  NSLog(@"didDiscoverServices:%@",peripheral.name);
  if (error) {
  NSLog(@"didDiscoverServices error:%@",[error localizedDescription]);
  return;
  }

  for (CBService *service in peripheral.services) {
  //發(fā)現(xiàn)特征，成功后執(zhí)行：peripheral:didDiscoverCharacteristicsForService:error委托方法
  [peripheral discoverCharacteristics:nil forService:service];
  }
  }

//已經(jīng)為服務(wù)發(fā)現(xiàn)特征
/*
藍(lán)牙都會(huì)有幾個(gè)服務(wù)，每個(gè)服務(wù)都會(huì)有幾個(gè)特征，服務(wù)和特征都是用不同的 UUID 來標(biāo)識(shí)的。
每個(gè)特征的 properties 是不同的，就是說有不同的功能屬性，有的對(duì)應(yīng)寫入，有的對(duì)應(yīng)讀取。
藍(lán)牙聯(lián)盟有一個(gè)規(guī)范，但是這個(gè)也是可以自定義的，所以不清楚的話，聯(lián)系硬件工程師問清楚
*/

• (void)peripheral:(CBPeripheral *)peripheral didDiscoverCharacteristicsForService:(CBService *)service error:(NSError *)error
  {
  NSLog(@"didDiscoverCharacteristicsForServic:%@",service.UUID);

  CBCharacteristic *characteristic = nil;

  if ([service.UUID isEqual:[CBUUID UUIDWithString:@"這里填你的藍(lán)牙服務(wù)的 UUID"]]) {
  for (characteristic in service.characteristics)
  {
  if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:@"這里填你的藍(lán)牙特征的 UUID"]]) {
  self.characteristic = characteristic;//重要，將滿足條件的特征保存為全局特征，以便對(duì)齊進(jìn)行寫入操作。
  [PRTBluetoothModel share].characteristicWrite = characteristic;
  [self.peripheral setNotifyValue:YES forCharacteristic:characteristic];
  }
  }
  }

  if (error) {
  NSLog(@"didDiscoverCharacteristicsForService error:%@",[error localizedDescription]);
  }
  }
  // 已經(jīng)更新特征的值
  //獲取外設(shè)發(fā)來的數(shù)據(jù)，不論是read和notify,獲取數(shù)據(jù)都是從這個(gè)方法中讀取。

• (void)peripheral:(CBPeripheral *)peripheral didUpdateValueForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error
  {
  NSLog(@"didUpdateValueForCharacteristic:%@",[characteristic.UUID UUIDString]);
  if (error) {
  NSLog(@"didUpdateValueForCharacteristic error:%@",[error localizedDescription]);
  }

  for (CBDescriptor *descriptor in characteristic.descriptors) //12.23新增
  {
  [peripheral readValueForDescriptor:descriptor];
  }
  }
  //已經(jīng)寫入特征的值
  //委托方法：已經(jīng)為特征【寫入值】
  -(void)peripheral:(CBPeripheral *)peripheral didWriteValueForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error
  {
  NSLog(@"didWriteValueForCharacteristic:%@",[characteristic.UUID UUIDString]);

  if (error) {
  NSLog(@"didWriteValueForCharacteristic error：%@",[error localizedDescription]);
  }

  [peripheral readValueForCharacteristic:characteristic]; //12.23新增
  }
  //已經(jīng)發(fā)現(xiàn)特征的描述

• (void)peripheral:(CBPeripheral *)peripheral didDiscoverDescriptorsForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error
  {
  NSLog(@"didDiscoverDescriptorsForCharacteristic:%@",characteristic);
  for (CBDescriptor *d in characteristic.descriptors) {
  NSLog(@"Descriptor UUID:%@",d.UUID);
  }
  }
  // 已經(jīng)更新描述的值

• (void)peripheral:(CBPeripheral *)peripheral didUpdateValueForDescriptor:(CBDescriptor *)descriptor error:(NSError *)error
  {
  NSLog(@"didUpdateValueForDescriptor:%@",descriptor);
  [peripheral readValueForDescriptor:descriptor]; //12.23新增
  }
  //已經(jīng)更新特征的通知狀態(tài)

• (void)peripheral:(CBPeripheral *)peripheral didUpdateNotificationStateForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error {
  NSLog(@"didUpdateNotificationStateForCharacteristic:%@",characteristic);

  [peripheral readValueForCharacteristic:characteristic]; //12.23新增
  [peripheral discoverDescriptorsForCharacteristic:characteristic];
  }