Question

我有一个Android应用程序，每60秒扫描一次BT设备。我在三个相同的设备中测试相同的应用程序（Moto X Play，2个使用Lollipop，1个使用Marshmallow），但是，在其中一个Lollipop手机中，startDiscovery（）方法在几分钟正常运行后停止检测设备。我知道因为这个调试行每分钟打印一次："Bluetooth is starting a new discovery"并且都没有收到BluetoothAdapter.ACTION_DISCOVERY_STARTED或BluetoothAdapter.ACTION_DISCOVERY_FINISHED个事件

这是负责收听BT事件的BroadcastReceiver的onReceive方法内的代码：

       if (intent.getAction().equals(ACTION_AWARE_BLUETOOTH_REQUEST_SCAN)) {

                if (bluetoothAdapter == null) {
                    Log.d(TAG, "Bluetooth adapter is not present");
                } else if (!bluetoothAdapter.isEnabled()) {
                    //Bluetooth is off
                    Log.d(TAG, "Bluetooth adapter is turned off...");
                }else{
                    if (bluetoothAdapter.isDiscovering()) {
                        Log.d(TAG, "Bluetooth adapter was discovering, cancelling...");
                        if(bluetoothAdapter.cancelDiscovery()){
                            Log.d(TAG, "Bluetooth adapter cancelled a previous discovery");
                        } else {
                            Log.d(TAG, "Bluetooth adapter could not cancel a previous discovery");
                        }
                    }

                    if (bluetoothAdapter.startDiscovery()) {
                        Log.d(TAG, "Bluetooth adapter is starting a new discovery");
                    } else {
                        Log.d(TAG, "Bluetooth adapter error on starting a new discovery");
                    }
                }
            }

我正在我的服务的onCreate方法中注册这样的BT动作：

        IntentFilter filter = new IntentFilter();
        filter.addAction(Bluetooth.ACTION_AWARE_BLUETOOTH_REQUEST_SCAN);
        filter.addAction(BluetoothDevice.ACTION_FOUND);
        filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
        filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
        filter.addAction(BluetoothAdapter.ACTION_STATE_CHANGED);
        registerReceiver(bluetoothMonitor, filter);

        Intent backgroundService = new Intent(ACTION_AWARE_BLUETOOTH_REQUEST_SCAN);
        bluetoothScan = PendingIntent.getBroadcast(this, 0, backgroundService, PendingIntent.FLAG_UPDATE_CURRENT);

非常奇怪，有时我会在logcat中得到这个奇怪的输出：

03-01 16:57:31.768 1103-1300/? V/AlarmManager: sending alarm {16adb330 type 0 *walarm*:ACTION_AWARE_BLUETOOTH_REQUEST_SCAN}
03-01 16:57:31.788 21145-21145/? D/AWARE::Bluetooth: Bluetooth is starting a new discovery
03-01 16:57:31.802 1103-1103/? V/AlarmManager: done {16adb330, *walarm*:ACTION_AWARE_BLUETOOTH_REQUEST_SCAN} [40ms]
03-01 17:00:31.852 1103-1300/? V/AlarmManager: sending alarm {16adb330 type 0 *walarm*:ACTION_AWARE_BLUETOOTH_REQUEST_SCAN}
03-01 17:00:31.879 21145-21145/? D/AWARE::Bluetooth: Bluetooth is starting a new discovery
03-01 17:00:31.884 1103-1103/? V/AlarmManager: done {16adb330, *walarm*:ACTION_AWARE_BLUETOOTH_REQUEST_SCAN} [40ms]
03-01 17:00:46.187 3573-3630/? D/BluetoothGatt: cancelOpen() - device: 80:E4:DA:71:B5:13
03-01 17:00:46.189 3573-3630/? D/BluetoothGatt: cancelOpen() - device: 80:E4:DA:71:BC:69
03-01 17:00:46.191 3573-3630/? D/BluetoothGatt: cancelOpen() - device: 80:E4:DA:71:B4:C8
03-01 17:00:46.193 3573-3630/? D/BluetoothGatt: cancelOpen() - device: 80:E4:DA:71:A4:61
03-01 18:58:34.548 2017-10585/? D/BluetoothAdapter: startLeScan(): null
03-01 18:58:37.823 2017-10585/? D/BluetoothAdapter: stopLeScan()
03-01 18:58:37.826 2017-10585/? D/BluetoothLeScanner: could not find callback wrapper
03-01 18:58:40.375 2017-10585/? D/BluetoothAdapter: startLeScan(): null
03-01 18:58:44.408 2017-10585/? D/BluetoothAdapter: stopLeScan()
03-01 18:58:44.411 2017-10585/? D/BluetoothLeScanner: could not find callback wrapper
03-01 18:58:44.579 2017-10585/? D/BluetoothAdapter: startLeScan(): null
03-01 18:58:46.589 2017-10585/? D/BluetoothAdapter: stopLeScan()
03-01 18:58:46.591 2017-10585/? D/BluetoothLeScanner: could not find callback wrapper

蓝牙startDiscovery停止工作

0 个答案: