BluetoothEventLoop（2255）：设备属性已更改。蓝牙连接丢失

Question

I have a sample application which transfers 30 char length data through Bluetooth.Data transfer was proper for four days,and then disconnected.Then after,when ever connection is established after few minutes Bluetooth connection is lost.adding adb logs and code.

Why i am getting disconnect from platform due to device property change ? when will the device property change ? is the device property change is the reason to loose Bluetooth connection?

private static final UUID MY_UUID_SECURE = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");

private class ConnectThread extends Thread {
    private final BluetoothSocket mmSocket;
    private final BluetoothDevice mmDevice;
    private String mSocketType;

    public ConnectThread(BluetoothDevice device, boolean secure) {
        mmDevice = device;
        BluetoothSocket tmp = null;
        mSocketType = secure ? "Secure" : "Insecure";

        // Get a BluetoothSocket for a connection with the
        // given BluetoothDevice
        try {

                tmp = device.createRfcommSocketToServiceRecord(MY_UUID_SECURE);

        } catch (IOException e) {
            Log.e(TAG, "Socket Type: " + mSocketType + "create() failed", e);
        }
        mmSocket = tmp;
        Log.i("12345", "Socket set");
    }

    public void run() {
        Log.i("12345", "BEGIN mConnectThread SocketType:" + mSocketType);
        setName("ConnectThread" + mSocketType);

        // Always cancel discovery because it will slow down a connection
        mAdapter.cancelDiscovery();

        // Make a connection to the BluetoothSocket
        try {
            // This is a blocking call and will only return on a
            // successful connection or an exception
            mmSocket.connect();
        } catch (IOException e) {
            // Close the socket
            try {
                mmSocket.close();
                Log.i(TAG, "Closing Socket 3");
            } catch (IOException e2) {
                Log.e(TAG, "unable to close() " + mSocketType + " socket during connection failure", e2);
            }
            connectionFailed();
            return;
        }

        // Reset the ConnectThread because we're done
        synchronized (BluetoothChatService.this) {
            mConnectThread = null;
        }

        // Start the connected thread
        connected(mmSocket, mmDevice, mSocketType);
    }

Logs :

09-12 11:16:36.230 V/BluetoothEventLoop.cpp( 2255): event_filter: Received signal org.bluez.Device:PropertyChanged from /org/bluez/3179/hci0/dev_22_89_8E_A9_50_1C

09-12 11:16:36.230 D/BluetoothEventLoop( 2255): Device property changed

09-12 11:16:36.240 D/BluetoothA2DPStateReceiver(20246): BluetoothA2DPStateReceiver constructor call()

09-12 11:16:36.245 D/BluetoothA2DPStateReceiver(20246): onReceive(): action = android.bluetooth.device.action.ACL_DISCONNECTED

09-12 11:16:36.245 D/BluetoothA2DPStateReceiver(20246): ACTION_ACL_DISCONNECTED

09-12 11:16:36.245 D/BluetoothA2DPSinkInfo(20246): checkBlackListCarkit() : isBlackListCarkit false

09-12 11:16:36.660 D/KeyguardViewMediator( 2255): setHidden false

Answer 1

May be due to the link loss, BT adapter had initiated the property changed command to report link disconnected to the upper layers. Please check in multitple devices.