iOS 蓝牙4.0开发

背景：

1.iOS的蓝牙不能用来传输文件。
2.iOS与iOS设备之间进行数据通信，使用gameKit.framework
3.iOS与其他非iOS设备进行数据通信，使用coreBluetooth.framework

iOS中蓝牙的实现方案

iOS中提供了4个框架用于实现蓝牙连接
GameKit.framework（用法简单）
只能用于iOS设备之间的连接，多用于游戏（比如五子棋对战），从iOS7开始过期

MultipeerConnectivity.framework
只能用于iOS设备之间的连接，从iOS7开始引入，主要用于文件共享（仅限于沙盒的文件）

ExternalAccessory.framework
可用于第三方蓝牙设备交互，但是蓝牙设备必须经过苹果MFi认证（国内较少）

CoreBluetooth.framework（时下热门）
可用于第三方蓝牙设备交互，必须要支持蓝牙4.0
硬件至少是4s，系统至少是iOS6
蓝牙4.0以低功耗著称，一般也叫BLE（BluetoothLowEnergy）
目前应用比较多的案例：运动手坏、嵌入式设备、智能家居

下面具体介绍使用CoreBluetooth.framework的代码步骤：

//蓝牙系统库

#import <CoreBluetooth/CoreBluetooth.h>

//必须要由UUID来唯一标示对应的service和characteristic

#define kServiceUUID @"5C476471-1109-4EBE-A826-45B4F9D74FB9"

#define kCharacteristicHeartRateUUID @"82C7AC0F-6113-4EC9-92D1-5EEF44571398"

#define kCharacteristicBodyLocationUUID @"537B5FD6-1889-4041-9C35-F6949D1CA034"

@interface ViewController ()<CBCentralManagerDelegate,CBPeripheralDelegate>

@property (nonatomic,strong)CBCentralManager * centralManager;

@property (nonatomic,strong)CBPeripheral     * peripheral;

@end

1.创建中心角色

#import <CoreBluetooth/CoreBluetooth.h>
- (void)viewDidLoad

{

    [super viewDidLoad];

    //初始化蓝牙 central manager

    _centralManager = [[CBCentralManager alloc]initWithDelegate:self queue:dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0) options:nil];    

}

2.扫描外设

[manager scanForPeripheralsWithServices:nil options:@{CBCentralManagerRestoredStateScanOptionsKey:@(YES)}];

3.连接外设

- (void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI
{
        if([peripheral.name  isEqualToString:BLE_SERVICE_NAME]){
                [self connect:peripheral];
        }
s);
}       

-(BOOL)connect:(CBPeripheral *)peripheral{
        self.manager.delegate = self;
        [self.manager connectPeripheral:peripheral
                                options:[NSDictionary dictionaryWithObject:[NSNumber numberWithBool:YES] forKey:CBConnectPeripheralOptionNotifyOnDisconnectionKey]];
}

4.扫描外设中的服务和特征

- (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral
{ 

    NSLog(@"Did connect to peripheral: %@", peripheral);
    _testPeripheral = peripheral; 

    [peripheral setDelegate:self];  <br>//查找服务
    [peripheral discoverServices:nil]; 

}

发现服务：

- (void)peripheral:(CBPeripheral *)peripheral didDiscoverServices:(NSError *)error
{ 

    NSLog(@"didDiscoverServices"); 

    if (error)
    {
        NSLog(@"Discovered services for %@ with error: %@", peripheral.name, [error localizedDescription]); 

        if ([self.delegate respondsToSelector:@selector(DidNotifyFailConnectService:withPeripheral:error:)])
            [self.delegate DidNotifyFailConnectService:nil withPeripheral:nil error:nil]; 

        return;
    } 

    for (CBService *service in peripheral.services)
    {
         //发现服务
        if ([service.UUID isEqual:[CBUUID UUIDWithString:UUIDSTR_ISSC_PROPRIETARY_SERVICE]])
        {
            NSLog(@"Service found with UUID: %@", service.UUID);  <br>//查找特征
            [peripheral discoverCharacteristics:nil forService:service];
            break;
        } 

    }
}

发现服务中的特征：

- (void)peripheral:(CBPeripheral *)peripheral didDiscoverCharacteristicsForService:(CBService *)service error:(NSError *)error
{

    if (error)
    {
        NSLog(@"Discovered characteristics for %@ with error: %@", service.UUID, [error localizedDescription]);

        [self error];
        return;
    }

    NSLog(@"服务：%@",service.UUID);
    for (CBCharacteristic *characteristic in service.characteristics)
    {
       //发现特征
            if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:@"xxxxxxx"]]) {
                NSLog(@"监听：%@",characteristic);<br>//监听特征
                [self.peripheral setNotifyValue:YES forCharacteristic:characteristic];
            }

    }
}

5.与外设进行数据交互
读取数据：

- (void)peripheral:(CBPeripheral *)peripheral didUpdateValueForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error
{
    if (error)
    {
        NSLog(@"Error updating value for characteristic %@ error: %@", characteristic.UUID, [error localizedDescription]);
        self.error_b = BluetoothError_System;
        [self error];
        return;
    }

//    NSLog(@"收到的数据：%@",characteristic.value);
    [self decodeData:characteristic.value];
}

写数据：

NSData *d2 = [[PBABluetoothDecode sharedManager] HexStringToNSData:@"0x02"];
                [self.peripheral writeValue:d2 forCharacteristic:characteristic type:CBChar