Android之蓝牙设备使用

1. 首先需要在AndroidManifest.xml中导入以下权限：

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

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

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2. 把你手机的蓝牙设置设置为可用状态，这里有两步：

A.  获得BluetoothAdapter,如果返回值为null,说明设备不支持蓝牙

BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

if (mBluetoothAdapter == null) {

    // Device does not support Bluetooth

}

B. 打开蓝牙设备驱动，BluetoothAdapter.ACTION_REQUEST_ENABLE  打开一个对话框进行选择

if (!mBluetoothAdapter.isEnabled()) {

    Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);

    startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);

}

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3. 寻找蓝牙设备
A. 首先获取已配对的远端设备,并把设备的名字以及地址添加到adapter

Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();

// If there are paired devices

if (pairedDevices.size() > 0) {

    // Loop through paired devices

    for (BluetoothDevice device : pairedDevices) {

        // Add the name and address to an array adapter to show in a ListView

        mArrayAdapter.add(device.getName() + "\n" + device.getAddress());

    }

}

B. 然后通过BluetoothAdapter.startDiscovery启动蓝牙设备的搜索备，注意：这是一个异步方法，调用的时候立刻就会返回。为了获得搜寻的结果，必须在用户自己的Activity中注册一个BroadcastReceiver

// Create a BroadcastReceiver for ACTION_FOUND

private final BroadcastReceiver mReceiver = new BroadcastReceiver() {

    public void onReceive(Context context, Intent intent) {

        String action = intent.getAction();

        // When discovery finds a device

        if (BluetoothDevice.ACTION_FOUND.equals(action)) {

            // Get the BluetoothDevice object from the Intent

            BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);

            // Add the name and address to an array adapter to show in a ListView

            mArrayAdapter.add(device.getName() + "\n" + device.getAddress());

        }

    }

};

// Register the BroadcastReceiver

IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);

registerReceiver(mReceiver, filter); // Don't forget to unregister during onDestroy

C. 使你的设备能够被其他设备搜索到

Intent discoverableIntent = new

Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);

discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);

startActivity(discoverableIntent);

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4. 连接设备
A. 作为连接方的服务器

private class AcceptThread extends Thread {

    private final BluetoothServerSocket mmServerSocket;

 

    public AcceptThread() {

        // Use a temporary object that is later assigned to mmServerSocket,

        // because mmServerSocket is final

        BluetoothServerSocket tmp = null;

        try {

            // MY_UUID is the app's UUID string, also used by the client code

            tmp = mBluetoothAdapter.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);

        } catch (IOException e) { }

        mmServerSocket = tmp;

    }

 

    public void run() {

        BluetoothSocket socket = null;

        // Keep listening until exception occurs or a socket is returned

        while (true) {

            try {

                socket = mmServerSocket.accept();

            } catch (IOException e) {

                break;

            }

            // If a connection was accepted

            if (socket != null) {

                // Do work to manage the connection (in a separate thread)

                manageConnectedSocket(socket);

                mmServerSocket.close();

                break;

            }

        }

    }

 

    /** Will cancel the listening socket, and cause the thread to finish */

    public void cancel() {

        try {

            mmServerSocket.close();

        } catch (IOException e) { }

    }

}

B. 作为连接方的客户端

private class ConnectThread extends Thread {

    private final BluetoothSocket mmSocket;

    private final BluetoothDevice mmDevice;

 

    public ConnectThread(BluetoothDevice device) {

        // Use a temporary object that is later assigned to mmSocket,

        // because mmSocket is final

        BluetoothSocket tmp = null;

        mmDevice = device;

 

        // Get a BluetoothSocket to connect with the given BluetoothDevice

        try {

            // MY_UUID is the app's UUID string, also used by the server code

            tmp = device.createRfcommSocketToServiceRecord(MY_UUID);

        } catch (IOException e) { }

        mmSocket = tmp;

    }

 

    public void run() {

        // Cancel discovery because it will slow down the connection

        mBluetoothAdapter.cancelDiscovery();

 

        try {

            // Connect the device through the socket. This will block

            // until it succeeds or throws an exception

            mmSocket.connect();

        } catch (IOException connectException) {

            // Unable to connect; close the socket and get out

            try {

                mmSocket.close();

            } catch (IOException closeException) { }

            return;

        }

 

        // Do work to manage the connection (in a separate thread)

        manageConnectedSocket(mmSocket);

    }

 

    /** Will cancel an in-progress connection, and close the socket */

    public void cancel() {

        try {

            mmSocket.close();

        } catch (IOException e) { }

    }

}

5. 设备连接时候的数据传输

private class ConnectedThread extends Thread {

    private final BluetoothSocket mmSocket;

    private final InputStream mmInStream;

    private final OutputStream mmOutStream;

 

    public ConnectedThread(BluetoothSocket socket) {

        mmSocket = socket;

        InputStream tmpIn = null;

        OutputStream tmpOut = null;

 

        // Get the input and output streams, using temp objects because

        // member streams are final

        try {

            tmpIn = socket.getInputStream();

            tmpOut = socket.getOutputStream();

        } catch (IOException e) { }

 

        mmInStream = tmpIn;

        mmOutStream = tmpOut;

    }

 

    public void run() {

        byte[] buffer = new byte[1024];  // buffer store for the stream

        int bytes; // bytes returned from read()

 

        // Keep listening to the InputStream until an exception occurs

        while (true) {

            try {

                // Read from the InputStream

                bytes = mmInStream.read(buffer);

                // Send the obtained bytes to the UI activity

                mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer)

                        .sendToTarget();

            } catch (IOException e) {

                break;

            }

        }

    }

 

    /* Call this from the main activity to send data to the remote device */

    public void write(byte[] bytes) {

        try {

            mmOutStream.write(bytes);

        } catch (IOException e) { }

    }

 

    /* Call this from the main activity to shutdown the connection */

    public void cancel() {

        try {

            mmSocket.close();

        } catch (IOException e) { }

    }

}