大于6.0系统 蓝牙扫描 LeScanCallback 方法 不

公司的 app 要链接BLE蓝牙设备,最近发现在 6.0 系统,startLeScan(mLeScanCallback);回调不触发.查资料发现 >6.0 需要一个模糊位置权限才能使用蓝牙,至于为什么蓝牙需要位置权限,我也很意外.

解决思路
1.1 清单加入位置权限(有可能清单中已经具备了)

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

1.2 动态请求权限(关键)

 private static final int REQUEST_COARSE_LOCATION = 0;

    private void mayRequestLocation() {
        if (Build.VERSION.SDK_INT >= 23) {
            int checkCallPhonePermission = ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION);
            if (checkCallPhonePermission != PackageManager.PERMISSION_GRANTED) {
                //判断是否需要 向用户解释，为什么要申请该权限
                if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.ACCESS_COARSE_LOCATION))
                    Toast.makeText(this, "动态请求权限", Toast.LENGTH_LONG).show();
                ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_COARSE_LOCATION}, REQUEST_COARSE_LOCATION);
                return;
            } else {

            }
        } else {

        }
    }
 //系统方法,从requestPermissions()方法回调结果
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        //确保是我们的请求
        if (requestCode == REQUEST_COARSE_LOCATION) {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                Toast.makeText(this, "权限被授予", Toast.LENGTH_SHORT).show();
            } else if (grantResults[0] != PackageManager.PERMISSION_GRANTED) {
                Toast.makeText(this, "权限被拒绝", Toast.LENGTH_SHORT).show();
            }
        } else {
            super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        }
    }

1.3 当用户点击始终允许后就可以正常运行了