Android 蓝牙五子棋[可人机对战] —— 蓝牙通信篇

前言

我之前做了个人机对战的五子棋, AI算法很垃圾, 然后各种逻辑很糟糕, 已经很久没有维护了, 今天看了篇文章, 是用了蓝牙和Wifi的五子棋对战, 我觉得很有意思, 毕竟自己没做过蓝牙连接这方面的项目, 然后我就把以前做的五子棋搬了出来.

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蓝牙基础知识

• 官方知识:

  设置蓝牙、查找局部区域内的配对设备或可用设备、连接设备，以及在设备之间传输数据。

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• 设置权限

  权限是一定要设置的,不然根本无法使用,在Manifest设置以下权限:

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

  关于6.0以上的蓝牙权限问题

  我是基于6.0开发的, 然而我开启了蓝牙却搜索不到其他设备, 感觉很奇怪,搜索了一下,原来:还要添加一个权限(其中一个):

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

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• 设置蓝牙

  1. 获取BluetoothAdapter

     所有蓝牙Activity都需要BluetoothAdapter,获取这个Adapter很简单, 只需要调用BluetoothAdapter.getDefaultAdapter()这个静态方法即可,它会返回本机的蓝牙适配器.

  2. 启用蓝牙可见性

     首先检测是否已开启蓝牙可见性, 然后使用

     if(!mBluetoothAdapter.isEnabled())
     {
         Intent openIntent=new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
         openIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 500); //设置可见性的时间500s, 0为一直可见
         startActivity(openIntent);
     }

     提示:启用可见性就会启动蓝牙.

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• 查找设备

  • 监听广播:

    当我们调用BluetoothAdapter.startDiscovery()扫描的时候, 会发出有ACTION_FOUND的广播, 并且Intent还带有EXTRA_DEVICE(包含BluetoothDevice),请看下面代码:

    public class BluetoothReceiver extends BroadcastReceiver {
    
        private List mDevices;
        private List mBluetoothList;
        public OnReceiverListener mOnReceiverListener;
    
        public BluetoothReceiver(List devices, List bluetooths, OnReceiverListener onReceiverListener) {
            mOnReceiverListener = onReceiverListener;
            mDevices = devices;
            mBluetoothList = bluetooths;
        }
    
        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            if (BluetoothDevice.ACTION_FOUND.equals(action)) {
                ///获取扫描到的Device信息
                BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
                if (!mDevices.contains(device)) {
                    Bluetooth bluetooth = new Bluetooth(device.getName(), device.getAddress());
                    mBluetoothList.add(bluetooth);
                    mDevices.add(device);
                }
            } else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
                mOnReceiverListener.showText();
            }
    
            if (mOnReceiverListener != null) {
                mOnReceiverListener.setBluetoothList(mBluetoothList, mDevices);
            }
        }
    
        //设置给BluetoothActivity的回调接口
        public interface OnReceiverListener {
            void setBluetoothList(List bluetooths, List devices);
            void showText();
        }
    }

    注意: 别忘了再Activity里注册和销毁Receiver

  • BluetoothActivity里的扫描

    直接调用startDiscovery()就可以了,很简单.

    //初始化
    private void init() {
        mBluetooths = new ArrayList<>();
        mDevices = new ArrayList<>();
    
        //初始化BluetoothAdpter
        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        if (!mBluetoothAdapter.isEnabled()) {
            openBluetooth();
        }
        mName = mBluetoothAdapter.getName();
        mAdress = mBluetoothAdapter.getAddress();
    
        //初始化ListView
        mAdapter = new BluetoothDevicesAdapter(mBluetooths, this);
        mLvBluetooth.setAdapter(mAdapter);
    
        //实例化广播
        mReceiver = new BluetoothReceiver(mDevices, mBluetooths, new BluetoothReceiver.OnReceiverListener() {
            @Override
            public void setBluetoothList(List bluetooths, List devices) {
                mBluetooths = bluetooths;
                mDevices = devices;
                mAdapter.setDevices(mBluetooths);
                mAdapter.notifyDataSetChanged();
            }
    
            @Override
            public void showText() {
                Toast.makeText(BluetoothActivity.this, "搜索完成!", Toast.LENGTH_SHORT).show();
            }
        });
    
        //注册广播
        IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
        registerReceiver(mReceiver, filter);
        filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
        registerReceiver(mReceiver, filter);
    
        mLvBluetooth.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView parent, View view, int position, long id) {
                connectBluetooth(position);
            }
        });
    }
    
    //查找设备
    private void findBluetooth() {
        if (mBluetoothAdapter.isDiscovering()) {    //中断搜索
            mBluetoothAdapter.cancelDiscovery();
        }
        mBluetooths.clear();
        mDevices.clear();
    
        //获取已配对的设备
        Set devices = mBluetoothAdapter.getBondedDevices();
        if (devices.size() > 0) {
            for (BluetoothDevice device : devices) {
                if (!mDevices.contains(device)) {
                    mBluetooths.add(new Bluetooth(device.getName(), device.getAddress()));
                    mDevices.add(device);
                }
            }
        }
        mAdapter.setDevices(mBluetooths);
        mAdapter.notifyDataSetChanged();
        mBluetoothAdapter.startDiscovery();
    }

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• 连接设备

  连接设备需要同时实现服务端和客服端, 因为其中一台设备必须开放服务器套接字, 另一台设备发起连接(使用服务器设备MAC地址), 当服务器和客户端在同一RFCOMM通道上分别拥有已连接的BluetoothSocket时, 此时就是彼此连接.

  提示: 若两台设备未配对, 则会先进行配对, 知道配对成功才会进行连接.

  • 建立服务器

    当需要连接时, 其中一台设备需要开放BluetoothServerSocket来充当服务器, 服务器套接字是用来侦听传入的连接请求, 并在接收后提供已连接的BluetoothSocket.

    • 获取BluetoothServerSocket

      通过调用listenUsingRfcommWithServiceRecord(String , UUID)获取BluetoothServerSocket.其中字符串是任意名称, UUID必须唯一标识, 两个UUID必须匹配.

      UUID: 通用唯一标识符, UUID足够庞大,可以使用随机, 可使用UUID.fromString(String)初始化

    • 侦听连接

      调用accept()来侦听, 需要放在子线程中, 只有当发送的请求中的UUID与服务器套接字UUID相匹配时, 才会被接受.返回已连接的BluetoothSocket.

    • 释放Server

      如果不需要与更多的连接,那么可以调用close()来释放所有资源.并不会关闭accept的已连接的BluetoothSocket.

      //初始化Scocket
      private void initSocket() {
          new Thread(new Runnable() {
              @Override
              public void run() {
                  try {
                      while (true) {
                          mServerSocket = mBluetoothAdapter.listenUsingRfcommWithServiceRecord(mName, ConfigData.UUID);
                          mSocket = mServerSocket.accept();
                          if (mSocket.isConnected()) {
                              InputStream is = mSocket.getInputStream();
                              byte[] buffer = new byte[1024];
                              int count = is.read(buffer);
                              final String result = new String(buffer, 0, count, "utf-8");
                              runOnUiThread(new Runnable() {
                                  @Override
                                  public void run() {
                                      AlertDialog aDialog = new AlertDialog.Builder(BluetoothActivity.this)
                                              .setTitle("消息")
                                              .setMessage("是否接受" + result + "的挑战?")
                                              .setPositiveButton("是", new DialogInterface.OnClickListener() {
                                                  @Override
                                                  public void onClick(DialogInterface dialog, int which) {
                                                      Toast.makeText(BluetoothActivity.this, "连接成功!", Toast.LENGTH_SHORT).show();
                                                  }
                                              })
                                              .setNegativeButton("否", null)
                                              .show();
                                  }
                              });
                              if(is!=null){
                                  is.close();
                              }
                          }
                      }
                  } catch (Exception e) {
                      e.printStackTrace();
                  } finally {
                  }
              }
          }).start();
      }

  ---

  • 建立客户端

    主要是为了能然上面的ServerSocket接收到请求.

    • 获取BluetoothSocket

      先获取需要连接设备的Device, 然后调用 device.createRfcommSocketToServiceRecord(ConfigData.UUID);就能够获取然后再调用bluetoothSocket.connect()就可以发起连接了

      注: 调用connect()时, 最好不要进行其他的蓝牙操作, 不然连接速度很慢, 也有可能会失败.

      // 开始连接对方
      private void connectBluetooth(int position) {
          BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(mBluetooths.get(position).getAdress());
          try {
              mThisSocket = device.createRfcommSocketToServiceRecord(ConfigData.UUID);
              //弹出对话框
              AlertDialog dialog = new AlertDialog.Builder(BluetoothActivity.this)
                      .setTitle("发起挑战")
                      .setMessage("确认挑战玩家: " + mBluetooths.get(position).getName())
                      .setPositiveButton("确定", new DialogInterface.OnClickListener() {
                          @Override
                          public void onClick(DialogInterface dialog, int which) {
                              new Thread(new Runnable() {
                                  @Override
                                  public void run() {
                                      OutputStream os = null;
                                      if (mBluetoothAdapter.isDiscovering()) {
                                          mBluetoothAdapter.cancelDiscovery();
                                      }
                                      try {
                                          mThisSocket.connect();                  //发起连接
                                          if (!mBluetoothAdapter.isEnabled()) {   //若未开启蓝牙,则打开
                                              mBluetoothAdapter.enable();
                                          }
                                          if (mThisSocket.isConnected()) {        //若已连接成功
                                              os = mThisSocket.getOutputStream(); //获得输出流
                                              os.write(mName.getBytes("utf-8"));  //向服务端发送本机蓝牙名称
                                              runOnUiThread(new Runnable() {      //在UI线程发送提示.
                                                  @Override
                                                  public void run() {
                                                      Toast.makeText(BluetoothActivity.this, "连接成功!!!", Toast.LENGTH_SHORT).show();
                                                  }
                                              });
                                          }
                                          if (os != null) {
                                              os.close();
                                          }
                                      } catch (Exception e) {
                                          e.printStackTrace();
                                      }
      
                                  }
                              }).start();
                          }
                      })
                      .setNegativeButton("取消", null)
                      .show();
          } catch (Exception e) {
              runOnUiThread(new Runnable() {
                  @Override
                  public void run() {
                      Toast.makeText(BluetoothActivity.this, "连接失败!", Toast.LENGTH_SHORT).show();
                  }
              });
              e.printStackTrace();
          }
      }

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总结

• 这里简单的说了下蓝牙的连接和管理，其实差不多都是官网的教程，百度到的教程十分的少，都是去官网看的，官网也有中文版，所以担心自己英语不好的兄弟们不要怕，就是干。

• 完整版的篇章：http://blog.csdn.net/williamchew/article/details/69566878

• 完整版对蓝牙连接的Socket线程进行了优化, 并使用了管理类，可能看起来会比较难懂，其实很简单，也有写的不好的地方，请原谅。