iOS蓝牙：中央外围设备在接受配对请求之前已连接

Question

蓝牙连接时出现问题，因为我正在按照CBCentral和CBPeripherel概念与一台设备进行通讯。 但是，Peripherel设备在接受配对请求之前就已连接到Central，基本上Central在接受配对请求之前将一些数据传递给外围设备。

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

{

for (CBCharacteristic *characteristic in service.characteristics)
{

    NSLog(@"for loop for charactersitc %@",characteristic.UUID);
    // And check if it's the right one
    if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:TRANSFER_SLIDEINDEX_CHARACTERISTIC_UUID]])
    {
        // If it is, subscribe to it
        [peripheral setNotifyValue:YES forCharacteristic:characteristic];
    }
    if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:TRANSFER_SCROLL_CHARACTERISTIC_UUID]])
    {
        // If it is, subscribe to it
        [peripheral setNotifyValue:YES forCharacteristic:characteristic];
    }

    if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:TRANSFER_FULLSCREEN_CHARACTERISTIC_UUID]])
    {
        // If it is, subscribe to it
        [peripheral setNotifyValue:YES forCharacteristic:characteristic];
    }
    if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:SLIDELENGTH_CHARACTERISTIC_UUID]])
    {
        // WRITE VALUES TO REMOTE
        NSInteger length = self.presentationDataSourceArray.count;
        NSData *chunk = [NSData dataWithBytes: &length length: sizeof(length)];

        [self.discoveredPeripheral writeValue:chunk forCharacteristic:characteristic
                                         type:CBCharacteristicWriteWithResponse];
        [self.discoveredPeripheral setNotifyValue:YES forCharacteristic:characteristic];

    }
    if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:DEVICENAME_CHARACTERISTIC_UUID]])
    {
        NSString *deviceName = [[UIDevice currentDevice]name];
        NSData *chunk = [deviceName dataUsingEncoding:NSUTF8StringEncoding];
        [self.discoveredPeripheral writeValue:chunk forCharacteristic:characteristic
                                         type:CBCharacteristicWriteWithResponse];
        [self.discoveredPeripheral setNotifyValue:YES forCharacteristic:characteristic];

        NSLog(@"Sending Device Name");
    }
    if ([characteristic.UUID isEqual: [CBUUID UUIDWithString:CURRENTSLIDE_CHARACTERISTIC_UUID]])
    {
        self.currentSlideIndexCharacterestics = (CBMutableCharacteristic*) characteristic;
        NSInteger count = self.currentPage;
        NSData *chunk = [NSData dataWithBytes: &count length: sizeof(count)];

        [self.discoveredPeripheral writeValue:chunk forCharacteristic:characteristic
                                         type:CBCharacteristicWriteWithResponse];
        [self.discoveredPeripheral setNotifyValue:YES forCharacteristic:characteristic];
    }


    _isRemoteConnected = YES;
}

Answer 1

问题不在您的APP中，而是在BLE设备中。
BLE设备的数据可以不成对写入和读取，完全可以。
仅当您尝试访问加密字符的数据时才启动配对请求，这是在外围设备侧配置的，如下所示：

emailCharacteristic = [[CBMutableCharacteristic alloc]
    initWithType:emailCharacteristicUUID
    properties:CBCharacteristicPropertyRead
    | CBCharacteristicPropertyNotifyEncryptionRequired
    value:nil permissions:CBAttributePermissionsReadEncryptionRequired];

因此，在您的情况下，外围设备的某些字符需要配对，而其他字符则不需要。

您可以在CorebluetoothGuide中看到更多