尝试检测BLE设备时未调用onLeScan函数

问题描述

我正在尝试检测服务附近的蓝牙低能耗设备.服务启动后，将调用 startLeScan()，然后在10秒钟后调用 stopLeScan().即使 startLeScan()返回true，但我没有收到任何错误，但 LeScanCallback 上的 onLeScan 不叫.服务:

I am trying to detect nearby Bluetooth Low-Energy devices on a service.When the service is started, startLeScan() is called, and then stopLeScan() is called after 10 seconds.Even though startLeScan() returns true, and I didn't get any error, onLeScan on the LeScanCallback was not called.the Service:

    .
    .
    .
            // Device scan callback.
        private BluetoothAdapter.LeScanCallback mLeScanCallback =
                new BluetoothAdapter.LeScanCallback() {

                    public void onLeScan(final BluetoothDevice device, final int rssi, final byte[] scanRecord) {
                        Log.i(TAG, "New LE Device: " + device.getName() + " @ " + rssi);
                        if (DEVICE_NAME.equals(device.getName()) && deviceAddress.equals(device.getAddress())) {
                            mDevice = device;
                            BleScan(false);
                            connectBluetoothDevice();
                        }
                    }
                };

    /**
     * Starts and stops Bluetooth LE scanning for BLE devices.
     *
     * @param enable true to start scanning, false to stop scanning.
     */
    public void scanLeDevice(final boolean enable) {
        if (enable) {
            // Stops scanning after a pre-defined scan period.
            mHandler.postDelayed(new Runnable() {
                @Override
                public void run() {
                    if (mScanning) {
                        BleScan(false);
                    }
                }
            }, SCAN_PERIOD);
            BleScan(true);
        } else {
            BleScan(false);
        }

    }

    /**
     * @param scan true to scan, and false to stop scanning for Bluetooth LE devices.
     */
    private void BleScan(boolean scan) {
        if (scan) {
            mScanning = true;
            boolean temp = mBluetoothAdapter.startLeScan(mLeScanCallback);
            Log.i(TAG, "Started LE scan: " + temp);
        } else {
            mScanning = false;
            mBluetoothAdapter.stopLeScan(mLeScanCallback);
        }
    }

我尝试使用 BluetoothLeScanner startScan()和 stopScan()，而是使用 ScanCallback 它没有帮助:

I tried to use BluetoothLeScanner startScan() and stopScan(), and using ScanCallback instead, but it didn't help:

    ScanCallback mScanCallback = new ScanCallback() {
        @Override
        public void onScanResult(int callbackType, ScanResult result) {
            Log.i(TAG, "New LE Device: " + result.getDevice().getName() + " @ " + result.getRssi());
        }

        @Override
        public void onScanFailed(int errorCode) {
            Log.i(TAG, "Scan Faild!!");
        }
    };


    /**
     * Starts and stops Bluetooth LE scanning for BLE devices.
     *
     * @param enable true to start scanning, false to stop scanning.
     */
    public void scanLeDevice(final boolean enable) {
        if (enable) {
            // Stops scanning after a pre-defined scan period.
            mHandler.postDelayed(new Runnable() {
                @Override
                public void run() {
                    if (mScanning) {
                        BleScan(false);
                    }
                }
            }, SCAN_PERIOD);
            BleScan(true);
        } else {
            BleScan(false);
        }

    }

    /**
     * @param scan true to scan, and false to stop scanning for Bluetooth LE devices.
     */
    private void BleScan(boolean scan) {
        if (scan) {
            mScanning = true;
            mBluetoothLeScanner.startScan(mScanCallback);
            Log.i(TAG, "Started LE scan");
        } else {
            mScanning = false;
            mBluetoothLeScanner.stopScan(mScanCallback);
        }
    }

有人说需要打开GPS，所以我打开了GPS.我尝试重新启动android设备.另一个BLE检测应用可以看到BLE设备.

some say GPS needs to be turned on, so I turned on GPS.I tried rebooting the android device.Another BLE detection app can see the BLE device.

为什么不调用扫描回调?

Why isn't the scan callback called?

修改

我正在运行Android 6.0.1的nexus 5设备上运行此应用程序.

I'm running this app on a nexus 5 device running Android 6.0.1 .

我尝试添加位置权限，但这没有帮助:

I tried adding location permission, but it didn't help:

( uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" )

推荐答案

我有类似的问题.相同的代码，一种平板电脑无法正常工作，而其他平板电脑则可以正常工作.我没有解决方案，但是当我重置平板电脑并重新安装apk时，它可以再次正常工作.

I have similar problem.Same code, one tablet not work but other does.I have no solution but when I reset my tablet and reinstall apk, it's can work fine again.

我发现了这个 onLeScan from BluetoothAdapter.LeScanCallback没有被调用Android棉花糖当我打开GPS时，就可以了...

I found this onLeScan from BluetoothAdapter.LeScanCallback not called in Android Marshmallowwhen I open gps, it's work...

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