Java BLE 不返回任何服务答案

【问题标题】：Java BLE returning no servicesJava BLE 不返回任何服务
【发布时间】：2016-09-26 20:39:08
【问题描述】：

我正在创建一个使用 BLE 与 MCU 通信的 Android 应用程序，目前我可以使用我的应用程序连接到 MCU，但是当我尝试发现并获取设备的服务时，我返回了一个空数组和我不确定为什么。

//Code used to connect to the device
private final BluetoothGattCallback mGattCallback = new BluetoothGattCallback() {
    @Override
    public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState){
        String intentAction;
        if (newState == BluetoothProfile.STATE_CONNECTED) {
            intentAction = ACTION_GATT_CONNECTED;
            mConnectionState = STATE_CONNECTED;
            broadcastUpdate(intentAction);
            Log.i("TAG", "Connected to GATT server.");
            // Attempts to discover services after successful connection.
            Log.i("TAG", "Attempting to start service discovery:" + mGatt.discoverServices());
            services = mGatt.getServices();
            System.out.println("Service 1 is : " + services.get(0));
        } else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
            intentAction = ACTION_GATT_DISCONNECTED;
            mConnectionState = STATE_DISCONNECTED;
            Log.i("TAG", "Disconnected from GATT server.");
            broadcastUpdate(intentAction);
        }
    }

输出：

09-26 16:33:09.648 10917-10931/bamboomobile.medhead I/TAG：已连接到 GATT 服务器。

09-26 16:33:09.648 10917-10931/bamboomobile.medhead D/BluetoothGatt：discoverServices() - 设备：DC:1B:A3:10:B9:D5

09-26 16:33:09.658 10917-10931/bamboomobile.medhead I/TAG：正在尝试启动服务发现：true

09-26 16:33:09.668 10917-10931/bamboomobile.medhead W/BluetoothGatt：回调中未处理的异常 java.lang.IndexOutOfBoundsException：索引 0 无效，大小为 0 在 java.util.ArrayList.throwIndexOutOfBoundsException(ArrayList.java:255) 在 java.util.ArrayList.get(ArrayList.java:308) 在bamboomobile.medhead.MainMenu$1.onConnectionStateChange(MainMenu.java:86) 在 android.bluetooth.BluetoothGatt$1.onClientConnectionState(BluetoothGatt.java:186) 在 android.bluetooth.IBluetoothGattCallback$Stub.onTransact(IBluetoothGattCallback.java:70) 在 android.os.Binder.execTransact(Binder.java:446)

09-26 16:33:09.688 10917-10931/bamboomobile.medhead D/BluetoothGatt: onSearchComplete() = Device=DC:1B:A3:10:B9:D5 Status=0

【问题讨论】：

标签： java android bluetooth-lowenergy

【解决方案1】：

连接后，您需要致电mGatt.discoverServices()。然后在onServicesDiscovered 回调中，您可以使用mGatt.getServices() 并继续。

【讨论】：