Question

我已在我的应用中实施了BLE中心。步骤：

获取BluetoothManager

mBluetoothManager =（BluetoothManager）mContext.getSystemService（Context.BLUETOOTH_SERVICE）;

mBluetoothAdapter = mBluetoothManager.getAdapter（）;
扫描设备
连接设备

mGatt = bluetoothDevice.connectGatt（this，false，gattCallback）;
处理回调并启动服务发现

设备连接后，我正在拨打电话来发现服务。

gatt.discoverServices();

一旦发现服务，我就会在

private final BluetoothGattCallback gattCallback = new BluetoothGattCallback() {
    @Override
    public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
        Log.i("onConnectionStateChange", "Status: " + status);
        switch (newState) {
            case BluetoothProfile.STATE_CONNECTED:
                Log.i("gattCallback", "STATE_CONNECTED");
                gatt.discoverServices();
                break;

            case BluetoothProfile.STATE_DISCONNECTED:
                mGatt = null;
                mBluetoothSingleTonClass.saveGatt(mGatt);
                deviceDisconnected();
                Log.e("gattCallback", "STATE_DISCONNECTED");
                break;

            case BluetoothProfile.STATE_CONNECTING :
                Log.e("gattCallback", "STATE_CONNECTING");
                break;

            default:
                Log.e("gattCallback", "STATE_OTHER");
        }
    }

    @Override
    public void onServicesDiscovered(BluetoothGatt gatt, int status) {

        List<BluetoothGattService> services = new ArrayList<>();
        services.addAll(gatt.getServices());

        Log.d("onServicesDiscovered", "uuid::" + gatt.getServices().get(0).getUuid());
        Log.d("onServicesDiscovered", "uuid::" + gatt.getServices().get(1).getUuid());
        Log.d("onServicesDiscovered", "uuid::" + gatt.getServices().get(2).getUuid());

        Log.d("onServicesDiscovered", "chars::" + gatt.getServices().get(2).getCharacteristics().size());
        Log.d("onServicesDiscovered", "chars::" + gatt.getServices().get(0).getCharacteristics().size());
        Log.d("onServicesDiscovered", "chars::" + gatt.getServices().get(1).getCharacteristics().size());


    }
};

问题是 gatt 为我提供了设备所具有的所有服务，但它在少数移动设备中提供了空特征数组。示例：gatt.getServices().get(0).getCharacteristics().size() 这在Nexus中运行良好，但几天后它给我空数组，即大小为零。我做错了吗？这是移动设备的问题吗？任何参考链接都会有所帮助。

Answer 1

如果设备在发现过程中断开连接，则可能会给出一个空（或太短）列表。您应检查回调中的状态代码，并假设服务在0（成功）时有效。

BLE onServicesDiscovered（）没有返回特征数组

1 个答案: