BluetoothLeScanner工作时未调用Android BluetoothAdapter.LeScanCallback onLeScan方法

Question

我正在尝试一些代码以将BLE设备连接到Android手机。 当我打电话时出现问题： scanLeDevice（true）

从不调用mLeScanCallback的onLeScan方法，但从Debug Logcat中可以看到BluethoothLeScanner从发现的设备中接收一些结果。

private BluetoothAdapter.LeScanCallback mLeScanCallback = new BluetoothAdapter.LeScanCallback() {
    @Override
    public void onLeScan(BluetoothDevice device, int rssi, byte[] scanRecord) {
        Log.i(TAG, device.getName());
    }
};

 private void scanLeDevice(final boolean enable) {
    if (enable) {
        // Stops scanning after a pre-defined scan period.
        Log.d(TAG,"scanLeDevice");
        mHandler.postDelayed(new Runnable() {
            @Override
            public void run() {
                mScanning = false;
                mBluetoothAdapter.stopLeScan(mLeScanCallback);
            }
        }, SCAN_PERIOD);

        mScanning = true;
        mBluetoothAdapter.startLeScan(mLeScanCallback);
    } else {
        mScanning = false;
        ready = -1;
        mBluetoothAdapter.stopLeScan(mLeScanCallback);
    }
}

我知道不推荐使用BluethhothAdapter.startLeScan（），甚至尝试使用startScan（）获得相同的结果。

我具有在AndroidManifest.xml上设置的权限

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="it.adacto.mysensortag">
<uses-feature
    android:name="android.hardware.bluetooth_le"
    android:required="true" />

<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

<uses-sdk android:minSdkVersion="18"
    android:targetSdkVersion="23"
    android:maxSdkVersion="24" />
<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">

<activity
    android:name=".AndroidPlugin"
    android:configChanges="orientation|keyboardHidden|screenSize"
    android:label="@string/app_name"
    android:theme="@style/FullscreenTheme">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />

        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>
</application>

Debug Logcat显示了Bluethooth Scanner的一些ScanResult，但是从未调用过Callback。我丢失了一些东西，但我不知道...

  first manudata for manu ID
  08-20 13:02:16.451 6243-6253/it.adacto.mysensortag 
  D/BluetoothLeScanner: onScanResult() - 
  ScanResult{mDevice=24:71:89:BC:81:80, mScanRecord=ScanRecord 
  [mAdvertiseFlags=5, mServiceUuids=[0000aa80-0000-1000-8000- 
 00805f9b34fb], mManufacturerSpecificData={13=[3, 0, 1]}, mServiceData= 
 {}, mTxPowerLevel=0, mDeviceName=CC2650 SensorTag], mRssi=-33, 
  mTimestampNanos=2904217657384005}
  08-20 13:02:16.551 6243-6252/it.adacto.mysensortag D/ScanRecord: 
  parseFromBytes
first manudata for manu ID
  08-20 13:02:16.551 6243-6252/it.adacto.mysensortag 
  D/BluetoothLeScanner: onScanResult() - 
  ScanResult{mDevice=24:71:89:BC:81:80, mScanRecord=ScanRecord 
  [mAdvertiseFlags=5, mServiceUuids=[0000aa80-0000-1000-8000- 
 00805f9b34fb], mManufacturerSpecificData={13=[3, 0, 1]}, mServiceData= 
 {}, mTxPowerLevel=0, mDeviceName=CC2650 SensorTag], mRssi=-33, 
  mTimestampNanos=2904217761182697}
  08-20 13:02:16.611 6243-6253/it.adacto.mysensortag D/ScanRecord: parseFromBytes
  08-20 13:02:16.611 6243-6253/it.adacto.mysensortag 
  D/BluetoothLeScanner: onScanResult() - 
  ScanResult{mDevice=00:13:04:19:CD:B9, mScanRecord=ScanRecord [mAdvertiseFlags=6, mServiceUuids=[0000ffe0-0000-1000-8000-00805f9b34fb, 
  0000fea3-0000-1000-8000-00805f9b34fb, 0000180a-0000-1000-8000- 
 00805f9b34fb], mManufacturerSpecificData={}, mServiceData={0000525d-0000-1000-8000-00805f9b34fb=[-98, -18]}, mTxPowerLevel=-2147483648, 
  mDeviceName=Beurer BF700], mRssi=-74, mTimestampNanos=2904217817201082}
  08-20 13:02:16.661 6243-6252/it.adacto.mysensortag D/ScanRecord: parseFromBytes

编辑： 我可以使用以下方法检查权限：

checkPermissions(){
 if (ActivityCompat.checkSelfPermission(AndroidPlugin.this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(AndroidPlugin.this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
      ActivityCompat.requestPermissions(AndroidPlugin.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 1);
      return;
  }else{
      Log.i(TAG,"PERMISSION ALREADY GIVEN ");
  }
  }