蓝牙BLE设备一旦连接就断开连接？

Question

I've been writing an app using Swift that connects to a bluetooth BLE device. For some reason, the app doesn't always connect to the device. In this case it will connect but gets disconnected straight away. This only happens maybe 1 in 10 times it connects, but definitely interferes with the reliability of the app. I'm using CoreBluetooth to connect to the BLE device. Attempting connection again usually always gets it to reconnect, and other apps that communicate with this device works correctly every time, so I'm confident that it is not a problem with the peripheral.

I'd just like to know if there is anyone out there who has had a similar issue or if there is a particular reason why this may be happening?

EDIT: Here's the code for the willSelectRow of my table. This is where I get the peripheral to connect.

    func tableView(tableView: UITableView, willSelectRowAtIndexPath indexPath: NSIndexPath) -> NSIndexPath? {

        centralManager.stopScan()
        connectingPeripheral.append(discoveredDeviceArrayInfo[indexPath.row])
        connectPeripheralNow(connectingPeripheral[0])

        return indexPath
}

This is where I get it to connect, at this point I select the row which sets the CBPeripheral details of the device to connect to.

connectPeripheralNow looks like this:

    func connectPeripheralNow(peripheral: CBPeripheral!){
    self.centralManager.connectPeripheral(peripheral, options: nil)
}

didConnectPeripheral and didDiscoverServices looks like this

    func centralManager(central: CBCentralManager,didConnectPeripheral peripheral: CBPeripheral)
{

    peripheral.delegate = self
    peripheral.discoverServices([CBUUID(string: "FFE5")])
    print("SUCCESS: Connected to " + peripheral.name!)
}

func peripheral(peripheral: CBPeripheral, didDiscoverServices error: NSError?)
{
    if let servicePeripherals = peripheral.services as [CBService]!
    {
        for servicePeripheral in servicePeripherals
        {
            print("INFORMATION: Service discovered " + String(stringInterpolationSegment: servicePeripheral.UUID))
            peripheral.discoverCharacteristics(nil, forService: servicePeripheral)

        }

    }
}

Just for the info, I do get a 'SUCCESS: Connected to xxx' message appear which shows that it is connecting. If you need more code, let me know!

Answer 1

What you are mentioning is more of an expected behaviour. BTLE is designed to consume very little amount of energy so it drops the connection as soon as possible. If you do not need a permanent connection then follow Discover --> Connect --> Read/write --> Setup timer --> When timer fires Connect.

If you need a permanent connection, you should subscribe for characteristic which transmits real time data like heart rate application. You would need to implement setNotifyValue:forCharacteristic: method. Read Apple Documentation for more details.