Question

我在Moto X上使用的是Android 4.4.2。我有一个自定义蓝牙低功耗板，当没有设备连接时，它会打开红色LED。它一次只支持一个连接的设备。我正在构建一个Android应用程序，它试图连接到这个BLE设备并写入其特性，然后断开它。我有两个问题：在为特征写一个值后，我正在做：

mBluetoothGatt.disconnect();
mBluetoothGatt.close();
mBluetoothGatt = null;
mBluetoothAdapter.cancelDiscovery();
broadcastUpdate(ACTION_GATT_DISCONNECTED);

但实际上并没有断开我的智能手机（BLE设备上的LED保持关闭状态，这意味着某些设备仍然连接到它）。但是，当我关闭智能手机上的蓝牙适配器时，LED会立即亮起。

第二个问题是我无法从第一次尝试中写出我的特征，我必须第二次调用相同的序列。

以下是调用我的字符编写的过程：

public void trytounlock() {
    Context context = getApplicationContext();
    if (connect("E2:0C:B9:4D:B9:56"))
    {
        Log.w(TAG, "connect returned true!");
    }
    else {
        Log.w(TAG, "connect returned false - warum?");
    };
    if (mBluetoothAdapter == null ) {
        Log.w(TAG, "BluetoothAdapter not initialized");
        return;
    }
     else
    {
        Log.w(TAG, "BluetoothAdapter initialized successfully!");
    }
    if ( mBluetoothGatt == null) {
        Log.w(TAG, "GATT not initialized");
        return;
    }
    else
    {
        Log.w(TAG, "GATT initialized succesfully!");
    }

    /*check if the service is available on the device*/
    BluetoothGattService mCustomService = mBluetoothGatt.getService(UUID.fromString("0000f00d-1212-efde-1523-785fef13d123"));
    while (!mBluetoothGatt.discoverServices())
    {
        Log.w(TAG, "Waiting for service discovery");
    }
    int duration = Toast.LENGTH_SHORT;
    if(mCustomService == null){
        Log.w(TAG, "Custom BLE Service not found here. ");
        return;
    }
    else
    {
        Log.w(TAG, "Custom BLE Service found successfully!");
    }
    BluetoothGattCharacteristic mWriteCharacteristic = mCustomService.getCharacteristic(UUID.fromString("0000beef-1212-efde-1523-785fef13d123"));
    byte[] raw={0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; 
        mWriteCharacteristic.setValue(raw);
    if(mBluetoothGatt.writeCharacteristic(mWriteCharacteristic) == false){
        Log.w(TAG, "Failed to write characteristic");
        Toast.makeText(context, "Failed to write characteristic - ошибочка!!", duration).show();
    }
    if (mBluetoothAdapter == null || mBluetoothGatt == null) {
        Log.w(TAG, "BluetoothAdapter not initialized, while trying to disconnect - weird!!!");
    }
    else {
        mBluetoothGatt.disconnect();
    }
    mWriteCharacteristic = null;
    mCustomService = null;
    if (mBluetoothGatt == null) {
    }
    else {
        mBluetoothGatt.disconnect();
        mBluetoothGatt.close();
        mBluetoothGatt = null;
        mBluetoothAdapter.cancelDiscovery();
    }
    broadcastUpdate(ACTION_GATT_DISCONNECTED);
}

这是我的连接程序：

    public boolean connect(final String address) {
     if (mBluetoothAdapter == null || address == null) {
        Log.w(TAG, "BluetoothAdapter not initialized or unspecified address.");
        return false;
    }

    final BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
    if (device == null) {
        Log.w(TAG, "Device not found.  Unable to connect.");
        return false;
    }
    // We want to directly connect to the device, so we are setting the autoConnect
    // parameter to false.
    mBluetoothGatt = device.connectGatt(this, false, mGattCallback);
    Log.d(TAG, "Trying to create a new connection.");
    mBluetoothDeviceAddress = address;
    mConnectionState = STATE_CONNECTING;
    return true;
}


// Implements callback methods for GATT events that the app cares about.  For example,
// connection change and services discovered.
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:" +
                    mBluetoothGatt.discoverServices());

        } else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
            intentAction = ACTION_GATT_DISCONNECTED;
            mConnectionState = STATE_DISCONNECTED;
            Log.i(TAG, "Disconnected from GATT server.");
            broadcastUpdate(intentAction);
        }
    }

    @Override
    public void onServicesDiscovered(BluetoothGatt gatt, int status) {
        if (status == BluetoothGatt.GATT_SUCCESS) {
            broadcastUpdate(ACTION_GATT_SERVICES_DISCOVERED);
        } else {
            Log.w(TAG, "onServicesDiscovered received: " + status);
        }
    }

    @Override
    public void onCharacteristicRead(BluetoothGatt gatt,
                                     BluetoothGattCharacteristic characteristic,
                                     int status) {
        if (status == BluetoothGatt.GATT_SUCCESS) {
            broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
        }
    }

    @Override
    public void onCharacteristicChanged(BluetoothGatt gatt,
                                        BluetoothGattCharacteristic characteristic) {
        broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
    }
};
private void broadcastUpdate(final String action) {
    final Intent intent = new Intent(action);
    sendBroadcast(intent);
}

所以，问题是：

如何正确释放我的主板，以便没有其他设备连接到它？
在我最初打开蓝牙适配器后第二次调用时，它只能写出我的特性是什么原因？

不与BLE设备断开连接

0 个答案: