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今天面试问我做过蓝牙灯泡没，现在正好看一下，最近智能家居很火

蓝牙就好像一个美女，我要在这个情人节的夜晚，把它衣服一件一件脱光光，嘿嘿

这个代码适配的是4.0，之后的我就不知道是否可行了，我在这只是了解下

1. 原理图

2. 蓝牙 API

获取本地蓝牙适配器    BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();    打开手机蓝牙    mBluetoothAdapter .enable();    关闭手机蓝牙    mBluetoothAdapter.disable();    扫描蓝牙设备    mBluetoothAdapter.startDiscovery();    取消扫描蓝牙设备,减少资源的消耗    mBluetoothAdapter.cancelDiscovery();

3. 添加蓝牙广播接受者

IntentFilter filter = new IntentFilter();// 开始扫描的广播filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);// 扫描完成的广播filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);// 发现一个可用的设备的广播filter.addAction(BluetoothDevice.ACTION_FOUND);mBluetoothReceiver = new BluetoothReceiver();//注册监听registerReceiver(mBluetoothReceiver, filter);

4. 蓝牙广播接受者

class BluetoothReceiver extends BroadcastReceiver {    @Override    public void onReceive(Context context, Intent intent) {        String action = intent.getAction();        //根绝不同的action做判断，eg:获取蓝牙设备    }}

5. 连接设备

public void connectServer(final BluetoothDevice device) {        new Thread(new Runnable(){            @Override            public void run() {                try {                    System.out.println(randomUUID.toString());                    BluetoothSocket clientSocket = device.                            createRfcommSocketToServiceRecord(                                    UUID.fromString("00001101-0000-1000-8000-00805f9b34fb"));                    clientSocket.connect();                    out = clientSocket.getOutputStream();                    System.out.println("连接成功");                    Looper.prepare();                    Toast.makeText(BluetoothDemoActivity.this, "连接成功", 0).show();                    Looper.loop();                } catch (IOException e) {                    e.printStackTrace();                }            }}).start();    }

6. 注销设备

注销广播接受者    @Override    protected void onDestroy() {        super.onDestroy();        unregisterReceiver(mBluetoothReceiver);    }

7. 代码

7.1 Activity

ublic class BlueToothActiity extends AppCompatActivity implements AdapterView.OnItemClickListener {    private ListView mLv;    private BluetoothAdapter mBluetoothAdapter;    private OutputStream mOutputStream;    private ArrayList
   
     mDevices = new ArrayList
    
     ();    private BroadcastReceiver mBluetoothReceiver = new BroadcastReceiver() {        @Override        public void onReceive(Context context, Intent intent) {            String action = intent.getAction();            if (BluetoothDevice.ACTION_FOUND.equals(action)) {                // 扫描到蓝牙设备                BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);                mDevices.add(device);                mAdapter.notifyDataSetChanged();                System.out.println("device name" + device.getName());            } else if (BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)) {                Toast.makeText(getApplicationContext(), "开始扫描", Toast.LENGTH_SHORT).show();            } else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {                Toast.makeText(getApplicationContext(), "扫描结束", Toast.LENGTH_SHORT).show();            }        }    };    private DeviceAdapter mAdapter;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        mLv = (ListView) findViewById(R.id.lv);        mAdapter = new DeviceAdapter(getApplicationContext(), mDevices);        mLv.setAdapter(mAdapter);        mLv.setOnItemClickListener(this);        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();        // 注册广播接收者, 当扫描到蓝牙设备的时候, 系统会发送广播        IntentFilter filter = new IntentFilter();        filter.addAction(BluetoothDevice.ACTION_FOUND);        filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);        filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);        registerReceiver(mBluetoothReceiver, filter);    }    public void clickBtn(View v) {        switch (v.getId()) {            case R.id.button1:                // 蓝牙是否可用                if (!mBluetoothAdapter.isEnabled()) {                    // 打开蓝牙                    mBluetoothAdapter.enable();                }                break;            case R.id.button2:                // 关闭蓝牙                if (mBluetoothAdapter.isEnabled()) {                    mBluetoothAdapter.disable();                }                break;            case R.id.button3:                // 开始扫描                mDevices.clear();                mAdapter.notifyDataSetChanged();                mBluetoothAdapter.startDiscovery();                break;            case R.id.button4:                // 停止扫描                mBluetoothAdapter.cancelDiscovery();                break;            case R.id.button5:                sendCtrl(0);                break;            case R.id.button6:                sendCtrl(1);                break;            case R.id.button7:                sendCtrl(2);                break;            default:                break;        }    }    private void sendCtrl(int i) {        try {            byte[] bs = new byte[5];            bs[0] = (byte)0x01;            bs[1] = (byte)0x99;            if(i== 0) {                bs[2] = (byte)0x10;                bs[3] = (byte)0x10;            }else if(i==1) {                bs[2] = (byte)0x11;                bs[3] = (byte)0x11;            }else if(i==2) {                bs[2] = (byte)0x17;                bs[3] = (byte)0x17;            }            bs[4] = (byte)0x99;            mOutputStream.write(bs);        } catch (IOException e) {            e.printStackTrace();        }    }    @Override    protected void onDestroy() {        super.onDestroy();        unregisterReceiver(mBluetoothReceiver);    }    @Override    public void onItemClick(AdapterView
      parent, View view, int position, long id) {        BluetoothDevice device = mDevices.get(position);        conn(device);    }    private void conn(final BluetoothDevice device) {        // 建立蓝牙连接是耗时操作, 类似TCP Socket, 需要放在子线程里        new Thread() {            public void run() {                try {                    // 获取 BluetoothSocket, UUID需要和蓝牙服务端保持一致                    BluetoothSocket bluetoothSocket = device.createRfcommSocketToServiceRecord(UUID                            .fromString("00001101-0000-1000-8000-00805F9B34FB"));                    // 和蓝牙服务端建立连接                    bluetoothSocket.connect();                    // 获取输出流, 往蓝牙服务端写指令信息                    mOutputStream = bluetoothSocket.getOutputStream();                    // 提示用户                    runOnUiThread(new Runnable() {                        public void run() {                            System.out.println("连接成功----");                            Toast.makeText(getApplicationContext(), "连接成功", Toast.LENGTH_SHORT)                                    .show();                        }                    });                } catch (IOException e) {                    e.printStackTrace();                }            };        }.start();    }}
    
   

7.2 Adapter

public class DeviceAdapter extends BaseAdapter {
       private ArrayList
   
     mDevices;    private Context mContext;    public DeviceAdapter(Context context, ArrayList
    
      devices) {        mDevices = devices;        mContext = context;    }    @Override    public int getCount() {        return mDevices.size();    }    @Override    public Object getItem(int position) {        return null;    }    @Override    public long getItemId(int position) {        return 0;    }    @Override    public View getView(int position, View convertView, ViewGroup parent) {        ViewHolder holder;        if(convertView == null) {            convertView = View.inflate(mContext, R.layout.bluetooth_item, null);            holder = new ViewHolder();            holder.mTvName = (TextView) convertView.findViewById(R.id.tv_name);            holder.mTvAddress = (TextView) convertView.findViewById(R.id.tv_address);            convertView.setTag(holder);        }else {            holder = (ViewHolder) convertView.getTag();        }        BluetoothDevice device = mDevices.get(position);        holder.mTvName.setText(device.getName());        holder.mTvAddress.setText(device.getAddress());        return convertView;    }    class ViewHolder {        TextView mTvName;        TextView mTvAddress;    }}
    
   

7.3 布局