蓝牙通信简介

什么是蓝牙通信

首先要知道几个类，BluetoothAdapter，BluetoothGatt，BluetoothDevice，BluetoothCattService，BluetoothCattCharacteristic。
BluetoothAdapter是蓝牙设配器，对蓝牙的操作都需要用到它，很重要,BluetoothGatt作为中央来使用和处理数据，使用时有一个回调方法BluetoothGattCallback返回中央的状态和周边提供的数据，BluetoothCattService作为周边来提供数据；BluetoothGattServerCallback返回周边的状态。BluetoothDevice是蓝牙设备，BluetoothCattCharacteristic是蓝牙设备的特征。
Android 平台包含蓝牙网络堆栈支持，此支持能让设备以无线方式与其他蓝牙设备交换数据。应用框架提供通过 Android Bluetooth API 访问蓝牙功能的权限。这些 API 允许应用以无线方式连接到其他蓝牙设备，从而实现点到点和多点无线功能。
原理：蓝牙通信和socket通信原理基本上是一致的

蓝牙通信的过程

1.首先开启蓝牙
2.搜索可用设备
3.创建蓝牙socket，获取输入输出流
4.读取和写入数据
5.断开连接关闭蓝牙

代码如下

客户端代码

package com.example.blue.connect;
 
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.os.Handler;
 
import java.io.IOException;
import java.util.UUID;
 
 
public class ConnectThread extends Thread {
    private static final UUID MY_UUID = UUID.fromString(Constant.CONNECTTION_UUID);
    private final BluetoothSocket mmSocket;
    private final BluetoothDevice mmDevice;
    private BluetoothAdapter mBluetoothAdapter;
    private final Handler mHandler;
    private ConnectedThread mConnectedThread;
 
    public ConnectThread(BluetoothDevice device, BluetoothAdapter adapter, Handler handler) {
     
        BluetoothSocket tmp = null;
        mmDevice = device;
        mBluetoothAdapter = adapter;
        mHandler = handler;
 
        try {
 
            tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
        } catch (IOException e) { }
        mmSocket = tmp;
    }
 
    public void run() {
 
        mBluetoothAdapter.cancelDiscovery();
 
        try {
 
            mmSocket.connect();
        } catch (Exception connectException) {
            mHandler.sendMessage(mHandler.obtainMessage(Constant.MSG_ERROR, connectException));
 
            try {
                mmSocket.close();
            } catch (IOException closeException) { }
            return;
        }
 
 
        manageConnectedSocket(mmSocket);
    }
 
    private void manageConnectedSocket(BluetoothSocket mmSocket) {
        mHandler.sendEmptyMessage(Constant.MSG_CONNECTED_TO_SERVER);
        mConnectedThread = new ConnectedThread(mmSocket, mHandler);
        mConnectedThread.start();
    }
 
 
    public void cancel() {
        try {
            mmSocket.close();
        } catch (IOException e) { }
    }
 
    public void sendData(byte[] data) {
        if( mConnectedThread!=null){
            mConnectedThread.write(data);
        }
    }
}

服务端代码

package com.example.blue.connect;
 
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothServerSocket;
import android.bluetooth.BluetoothSocket;
import android.os.Handler;
 
import java.io.IOException;
import java.util.UUID;
 
//服务器端线程
public class AcceptThread extends Thread {
    private static final String NAME = "BlueToothClass";
    private static final UUID MY_UUID = UUID.fromString(Constant.CONNECTTION_UUID);
 
    private final BluetoothServerSocket mmServerSocket;
    private final BluetoothAdapter mBluetoothAdapter;
    private final Handler mHandler;
    private ConnectedThread mConnectedThread;
 
    public AcceptThread(BluetoothAdapter adapter, Handler handler) {
 
        mBluetoothAdapter = adapter;
        mHandler = handler;
        BluetoothServerSocket tmp = null;
        try {
 
            tmp = mBluetoothAdapter.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);
        } catch (IOException e) { }
        mmServerSocket = tmp;
    }
 
    public void run() {
        BluetoothSocket socket = null;
 
        while (true) {
            try {
                mHandler.sendEmptyMessage(Constant.MSG_START_LISTENING);
                socket = mmServerSocket.accept();
            } catch (IOException e) {
                mHandler.sendMessage(mHandler.obtainMessage(Constant.MSG_ERROR, e));
                break;
            }
 
            if (socket != null) {
 
                manageConnectedSocket(socket);
                try {
                    mmServerSocket.close();
                    mHandler.sendEmptyMessage(Constant.MSG_FINISH_LISTENING);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                break;
            }
        }
    }
 
    private void manageConnectedSocket(BluetoothSocket socket) {
        //只支持同时处理一个连接
        if( mConnectedThread != null) {
            mConnectedThread.cancel();
        }
        mHandler.sendEmptyMessage(Constant.MSG_GOT_A_CLINET);
        mConnectedThread = new ConnectedThread(socket, mHandler);
        mConnectedThread.start();
    }
 
 
    public void cancel() {
        try {
            mmServerSocket.close();
            mHandler.sendEmptyMessage(Constant.MSG_FINISH_LISTENING);
        } catch (IOException e) { }
    }
 
    public void sendData(byte[] data) {
        if( mConnectedThread!=null){
            mConnectedThread.write(data);
        }
    }
}

共同处理通讯处理类代码

package com.example.blue.connect;
 
import android.bluetooth.BluetoothSocket;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
 
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
 
 
public class ConnectedThread extends Thread {
    private final BluetoothSocket mmSocket;
    private final InputStream mmInStream;
    private final OutputStream mmOutStream;
    private final Handler mHandler;
 
    public ConnectedThread(BluetoothSocket socket, Handler handler) {
        mmSocket = socket;
        InputStream tmpIn = null;
        OutputStream tmpOut = null;
        mHandler = handler;
 
        try {
            tmpIn = socket.getInputStream();
            tmpOut = socket.getOutputStream();
        } catch (IOException e) { }
 
        mmInStream = tmpIn;
        mmOutStream = tmpOut;
    }
 
 
    public void run() {
        byte[] buffer = new byte[1024]; 
        int bytes;
 
   
        //一直读数据
        while (true) {
            try {
 
                bytes = mmInStream.read(buffer);
 
                if( bytes >0) {
                    Message message = mHandler.obtainMessage(Constant.MSG_GOT_DATA, new String(buffer, 0, bytes, "utf-8"));
                    mHandler.sendMessage(message);
                }
                Log.d("GOTMSG", "message size" + bytes);
            } catch (IOException e) {
                mHandler.sendMessage(mHandler.obtainMessage(Constant.MSG_ERROR, e));
                break;
            }
        }
    }
 
    //发送数据
    public void write(byte[] bytes) {
        try {
            mmOutStream.write(bytes);
        } catch (IOException e) { }
    }
 
    public void cancel() {
        try {
            mmSocket.close();
        } catch (IOException e) { }
    }
}

Constant常量类代码

public class Constant {
 
    public static final String CONNECTTION_UUID = "00001101-0000-1000-8000-00805F9B34FB";
 
    /**
     * 开始监听
     */
 
    public static final int MSG_START_LISTENING = 1;
 
    /**
     * 结束监听
     */
    public static final int MSG_FINISH_LISTENING = 2;
 
    /**
     * 有客户端连接
     */
    public static final int MSG_GOT_A_CLINET = 3;
 
    /**
     * 连接到服务器
     */
    public static final int MSG_CONNECTED_TO_SERVER = 4;
 
    /**
     * 获取到数据
     */
    public static final int MSG_GOT_DATA = 5;
 
    /**
     * 出错
     */
    public static final int MSG_ERROR = -1;
 
}

BlueToothController蓝牙控制类代码

public class BlueToothController {
    private BluetoothAdapter mAapter;
 
    public BlueToothController() {
        mAapter = BluetoothAdapter.getDefaultAdapter();
    }
 
    public BluetoothAdapter getAdapter() {
        return mAapter;
    }
    /**
     * 打开蓝牙
     * @param activity
     * @param requestCode
     */
    public void turnOnBlueTooth(Activity activity, int requestCode) {
        Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
        activity.startActivityForResult(intent, requestCode);
//        mAdapter.enable();
    }
 
    /**
     * 打开蓝牙可见性
     * @param context
     */
    public void enableVisibly(Context context) {
        Intent discoverableIntent = new
                Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
        discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);
        context.startActivity(discoverableIntent);
    }
 
    /**
     * 查找设备
     */
    public void findDevice() {
        assert (mAapter != null);
        mAapter.startDiscovery();
    }
 
    /**
     * 获取绑定设备
     * @return
     */
    public List<BluetoothDevice> getBondedDeviceList() {
        return new ArrayList<>(mAapter.getBondedDevices());
    }
}

蓝牙设备adaptor代码DeviceAdapter

public class DeviceAdapter extends BaseAdapter {
    private Context mContext;
    private List<BluetoothDevice> mDate;
 
    public DeviceAdapter(List<BluetoothDevice> Date, Context context){
        mDate = Date;
        mContext = context;
 
    }
    @Override
    public int getCount() {
        return mDate.size();
    }
 
    @Override
    public Object getItem(int position) {
        return mDate.get(position);
    }
 
    @Override
    public long getItemId(int position) {
        return position;
    }
 
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder viewHolder = null;
        if(convertView==null){
            viewHolder = new ViewHolder();
            convertView = LayoutInflater.from(mContext).inflate(R.layout.deviceadapter_layout,null);
            viewHolder.textView1 = (TextView)convertView.findViewById(R.id.textview1);
            viewHolder.textView2 = (TextView)convertView.findViewById(R.id.textview2);
            convertView.setTag(viewHolder);
        }else{
            viewHolder = (ViewHolder) convertView.getTag();
        }
        //获取蓝牙设备
        BluetoothDevice bluetoothDevice = (BluetoothDevice) getItem(position);
        viewHolder.textView1.setText("Name="+bluetoothDevice.getName());
        viewHolder.textView2.setText("Address"+bluetoothDevice.getAddress());
        return convertView;
    }
 
    public class ViewHolder{
        public TextView textView1;
        public  TextView textView2;
 
    }
    public void refresh(List<BluetoothDevice> data){
        mDate = data;
        notifyDataSetChanged();
    }
}