iOS 核心蓝牙 : centralManager:didConnectPeripheral/didFailToConnectPeripheral: not getting called

Question

我正在努力解决这个问题。我正在尝试连接到 BLE 设备，但在下面的代码中看不到我做错了什么。

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    _cm = [[CBCentralManager alloc] initWithDelegate:self queue:nil];
}

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
}


- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

+ (NSString*)UUIDString:(CFUUIDRef)uuid {
    CFStringRef string = CFUUIDCreateString(NULL, uuid);
    return (__bridge_transfer NSString*)string;
}

- (void)centralManagerDidUpdateState:(CBCentralManager *)central {
    if (central.state == CBCentralManagerStatePoweredOn) {
        [self scanForPeripherals];
    }
}

- (void)centralManager:(CBCentralManager *)central
 didDiscoverPeripheral:(CBPeripheral *)peripheral
     advertisementData:(NSDictionary *)advertisementData
                  RSSI:(NSNumber *)RSSI {
//    NSLog(@"Received peripheral : \n%@", peripheral);
//    NSLog(@"Adv data : %@", advertisementData);

    [peripheral setDelegate:self];
    [central connectPeripheral:peripheral options:nil];
    [peripheral readRSSI];
}

- (int)scanForPeripherals {
    NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
                             [NSNumber numberWithBool:NO], CBCentralManagerScanOptionAllowDuplicatesKey,
                             nil];

    [_cm scanForPeripheralsWithServices:nil options:options];
    return 0;
}

- (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral {
    NSLog(@"didConnectPeripheral");
}

- (void)centralManager:(CBCentralManager *)central didDisconnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error {
    NSLog(@"didDisconnectPeripheral");
}

- (void)centralManager:(CBCentralManager *)central didFailToConnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error {
    NSLog(@"failed to connect");
}

- (void)peripheral:(CBPeripheral *)peripheral didReadRSSI:(NSNumber *)RSSI error:(NSError *)error {
    NSLog(@"didReadRSSI");
}

这些设备不是我自己的。我不知道它的邻近 UUID，但据我所知，通过 CoreBluetooth 连接不需要它，对吗？

所有设备都在 didDiscoverPeripheral: 中发现，在我尝试连接它们的选择器中。但是之后什么也没有。

当我调用 didDiscoverPeripheral: 时，我是否期待与配对密码请求的对话？如果是这样，我没有看到任何对话框，这是为什么？

从 apple 文档中，它清楚地指出，在尝试连接到设备后，您应该调用 didConnectPeripheral 或 didFailToConnectPeripher 但我没有收到。

有什么想法吗？我已经尝试了将近一个星期了。感谢您的帮助，谢谢。

Answer 1

如果您不以某种方式保留传递给 didDiscoverPeripheral 的 peripheral 对象，那么一旦此委托(delegate)方法退出，它就会被释放，您将无法获得连接。

我建议添加一个属性来跟踪发现的外围设备

@property (strong,nonatomic) NSMutableArray *peripherals;

在 viewDidLoad 或 init 中初始化

self.peripherals=[NSMutableArray new];

然后在didDiscoverPeripheral中添加外设到它

-(void) centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI
{
    NSLog(@"Discovered peripheral %@",peripheral.identifier.UUIDString);
    [self.peripherals addObject:peripheral];
    [central connectPeripheral:peripheral options:nil];
}