Bluetooth Permission Request

  public static final boolean IS_BUILD_VERSION_LM = Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP;

    private static final int REQUEST_ENABLE_BLE = 1;
    private static final int RESULT_OK = -1;

    private static final int PERMISSION_GRANTED = PackageManager.PERMISSION_GRANTED;
    private static final String PERMISSION_COARSE = Manifest.permission.ACCESS_COARSE_LOCATION;
    private static final String PERMISSION_FINE = Manifest.permission.ACCESS_FINE_LOCATION;

    private static WeakReference<Activity> reference;


    @TargetApi(Build.VERSION_CODES.M)
    public static void requestBluetoothPermission(Activity activity) {
        reference = new WeakReference<>(activity);
        if (checkPermission(PERMISSION_COARSE) != PERMISSION_GRANTED || checkPermission(PERMISSION_FINE) != PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(reference.get(), new String[]{PERMISSION_COARSE, PERMISSION_FINE}, REQUEST_ENABLE_BLE);
        }
        reference.clear();
    }


    private static int checkPermission(String permissionTag) {
        return ContextCompat.checkSelfPermission(reference.get(), permissionTag);
    }


    public static void requestBluetoothEnable(Activity activity) {
        reference = new WeakReference<>(activity);
        Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
        ActivityCompat.startActivityForResult(reference.get(), intent, REQUEST_ENABLE_BLE, null);
        reference.clear();
    }


    public static void onRequestPermissionsResult(int requestCode, int[] grantResults, Activity activity) {
        reference = new WeakReference<>(activity);
        if (requestCode == BluetoothHelper.REQUEST_ENABLE_BLE) {
            if (grantResults.length != 0) {
                if (grantResults[0] == PERMISSION_GRANTED || grantResults[1] == PERMISSION_GRANTED) {
                    Toast.makeText(reference.get(), R.string.permission_thanks, Toast.LENGTH_SHORT).show();
                } else {
                    Intent myAppSettings = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS, Uri.parse("package:" + reference.get().getPackageName()));
                    myAppSettings.addCategory(Intent.CATEGORY_DEFAULT);
                    myAppSettings.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                    ActivityCompat.startActivityForResult(reference.get(), myAppSettings, 0, null);

                    Toast.makeText(reference.get(), R.string.permission_request, Toast.LENGTH_SHORT).show();
                    reference.get().finish();
                }
            }
        } else {
            Toast.makeText(reference.get(), R.string.permission_denial, Toast.LENGTH_SHORT).show();
        }
        reference.clear();
    }


    public static void onRequestEnableResult(int requestCode, int resultCode, Activity activity) {
        reference = new WeakReference<>(activity);
        if (requestCode == REQUEST_ENABLE_BLE && resultCode == RESULT_OK) {
            Toast.makeText(reference.get(), R.string.bluetooth_on, Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(reference.get(), R.string.bluetooth_not_init, Toast.LENGTH_SHORT).show();
            reference.get().finish();
        }
        reference.clear();
    }