基于蓝牙的安卓客户端开发

一.安卓蓝牙开发基本流程

• 获取本地蓝牙适配器，打开蓝牙，获得已配对蓝牙设备列表

mBtAdapter = BluetoothAdapter.getDefaultAdapter();

mBtAdapter.enable(); 

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

• 扫描未配对设备，通过广播（BluetoothDevice.ACTION_FOUND）接收列表出未配对的设备

mBtAdapter.startDiscovery();

• 从列表设备选择某个蓝牙进行连接，获得BluetoothDevice 对象

device.getName()

device.getAddress()

BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address)

• 开始连接线程，获得BluetoothSocket

private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");

BluetoothSocket bluetoothSocket= device.createRfcommSocketToServiceRecord(MY_UUID)

• 开始已连接线程，由BluetoothSocket获得输入输出流从而收发数据

二.权限申明

<!--蓝牙权限-->
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
    <uses-permission android:name="android.permission.BLUETOOTH" />

三.布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    >
    <!--标题栏-->
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#CDC9C9">
        <TextView
            android:id="@+id/DeviceTextView"
            android:layout_width="wrap_content"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:text="设备："
            android:textColor="#FFFFFF"
            android:textSize="20dp"
            />
        <TextView
            android:id="@+id/StateTextView"
            android:layout_width="wrap_content"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:text="状态："
            android:textColor="#FFFFFF"
            android:textSize="20dp"
            />
    </LinearLayout>
    <!--聊天界面-->
    <LinearLayout
        android:id="@+id/chatPage"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:visibility="gone"
        android:layout_marginLeft="10dp"
        android:layout_marginRight="10dp"
        >
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"

            >
            <EditText
                android:id="@+id/MessageEditText"
                android:layout_marginTop="5dp"
                android:layout_width="wrap_content"
                android:layout_weight="1"
                android:layout_height="40dp"
                />
            <Button
                android:id="@+id/SendButton"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="4dp"
                android:textAllCaps="false"
                android:text="Send"
                />
        </LinearLayout>
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <TextView
                android:id="@+id/DisplayTextView"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="DisplayTextView"/>
        </LinearLayout>

    </LinearLayout>
    <!--控制界面-->
    <LinearLayout
        android:id="@+id/controlPage"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:visibility="visible">
    </LinearLayout>
    <!--数据中心-->
    <LinearLayout
        android:id="@+id/displayPage"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:visibility="gone">
    </LinearLayout>
</LinearLayout>

四.具体代码实现

• MainActivity

package com.example.john.esdc;

import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.Intent;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    // Intent request codes
    private static final int REQUEST_CONNECT_DEVICE = 1;
    // Local Bluetooth adapter
    private BluetoothAdapter mBluetoothAdapter = null;
    // Member object for the chat services
    private BluetoothChatService mChatService = null;
    // Message types sent from the BluetoothChatService Handler
    public static final int MESSAGE_STATE_CHANGE = 1;
    public static final int MESSAGE_READ = 2;
    public static final int MESSAGE_WRITE = 3;
    public static final int MESSAGE_DEVICE_NAME = 4;
    public static final int MESSAGE_TOAST = 5;
    // Key names received from the BluetoothChatService Handler
    public static final String DEVICE_NAME = "device_name";
    public static final String TOAST = "toast";
    // Name of the connected device
    private String mConnectedDeviceName = null;
    //控件
    TextView deviceTextView;
    TextView stateTextView;
    EditText messageEditText;
    Button sendButton;
    TextView displayTextView;
    private int numofMessage=0; //显示的消息数
    //界面
    View controlPage;
    View displayPage;
    View chatPage;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        getWidget();
        // Initialize the BluetoothChatService to perform bluetooth connections
        mChatService = new BluetoothChatService(this, mHandler);
        // Get local Bluetooth adapter
        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        sendButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String message = messageEditText.getText().toString();
                sendMessage(message);
            }
        });
    }
    //获取控件对象
    private void getWidget(){
        deviceTextView = (TextView)findViewById(R.id.DeviceTextView);
        stateTextView = (TextView)findViewById(R.id.StateTextView);
        messageEditText = (EditText)findViewById(R.id.MessageEditText);
        sendButton = (Button)findViewById(R.id.SendButton);
        displayTextView = (TextView)findViewById(R.id.DisplayTextView);

        chatPage = (View)findViewById(R.id.chatPage);
        controlPage = (View)findViewById(R.id.controlPage);
        displayPage = (View)findViewById(R.id.displayPage);
    }
    //发送一条消息
    private void sendMessage(String message){
        if (mChatService.getState()!=BluetoothChatService.STATE_CONNECTED){
            Toast.makeText(this, "未连接蓝牙设备", Toast.LENGTH_SHORT).show();
            return;
        }
        if (message.length()>0){
            byte[] send = message.getBytes();
            mChatService.write(send);
            messageEditText.setText("");
        }
    }
    //*********************************************************************************
    //建立菜单
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.option_menu,menu);
        return true;
    }
    //菜单响应事件,主要完成界面切换
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()){
            case R.id.scan:  //点击“Scan”项，执行DeviceListActivity，在onActivityResult中返回用户点击连接的蓝牙MAC地址
                Intent serverIntent = new Intent(this,DeviceListActivity.class);
                startActivityForResult(serverIntent,REQUEST_CONNECT_DEVICE);
                return true;
            case R.id.chatPage:
                chatPage.setVisibility(View.VISIBLE);
                displayPage.setVisibility(View.GONE);
                controlPage.setVisibility(View.GONE);
                return true;
            case R.id.displayPage:
                chatPage.setVisibility(View.GONE);
                displayPage.setVisibility(View.VISIBLE);
                controlPage.setVisibility(View.GONE);
                return true;
            case R.id.controlPage:
                chatPage.setVisibility(View.GONE);
                displayPage.setVisibility(View.GONE);
                controlPage.setVisibility(View.VISIBLE);
                return true;
        }
        return false;
    }
    //**********************************************************************************************
    //获得DeviceList活动反馈回的蓝牙设备地址，获取BluetoothDevice，开始连接
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        switch (requestCode){
            case REQUEST_CONNECT_DEVICE:
                //获取蓝牙地址并执行连接
                if(resultCode== Activity.RESULT_OK){
                    String address = data.getExtras()
                            .getString(DeviceListActivity.EXTRA_DEVICE_ADDRESS);
                    BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
                    mChatService.connect(device);

                }
        }
    }
    //**********************************************************************************************
    //主要负责更新UI
    private final Handler mHandler = new Handler(){
        @Override
        public void handleMessage(Message msg) {

            switch (msg.what){
                case MESSAGE_STATE_CHANGE:
                    switch (msg.arg1){
                        case BluetoothChatService.STATE_CONNECTED:
                            stateTextView.setText("状态：已连接");
                            break;
                        case BluetoothChatService.STATE_CONNECTING:
                            stateTextView.setText("状态：正连接");
                            break;
                        case BluetoothChatService.STATE_NONE:
                            stateTextView.setText("状态：未连接");
                            break;
                    }
                    break;
                case MESSAGE_TOAST:
                    Toast.makeText(getApplicationContext(), msg.getData().getString(TOAST),
                            Toast.LENGTH_SHORT).show();
                    break;
                case MESSAGE_DEVICE_NAME:
                    mConnectedDeviceName = msg.getData().getString(DEVICE_NAME);
                    deviceTextView.setText("设备："+mConnectedDeviceName);
                    Toast.makeText(MainActivity.this, "已连接上"+mConnectedDeviceName, Toast.LENGTH_SHORT).show();
                    break;
                case MESSAGE_READ:
                    if (chatPage.getVisibility() == View.VISIBLE){
                        displayTextView.append(mConnectedDeviceName+"："+msg.obj+"
");
                        numofMessage++;
                        if (numofMessage==10) {
                            displayTextView.setText("");
                            numofMessage = 0;
                        }
                    }
                    break;
                case MESSAGE_WRITE:
                    byte[] writeBuf = (byte[]) msg.obj;
                    String writeMessage = new String(writeBuf);
                    if (chatPage.getVisibility() == View.VISIBLE){
                        displayTextView.append("本机："+writeMessage+"
");
                        numofMessage++;
                        if (numofMessage==10) {
                            displayTextView.setText("");
                            numofMessage = 0;
                        }
                    }
                    break;
            }
        }
    };
}

• DeviceListActivity

package com.example.john.esdc;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.Window;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.util.Set;

import static android.R.attr.filter;
@SuppressLint("NewApi")
public class DeviceListActivity extends AppCompatActivity {

    // Return Intent extra
    public static String EXTRA_DEVICE_ADDRESS = "device_address";

    // Member fields
    private BluetoothAdapter     mBtAdapter;
    private ArrayAdapter<String> mPairedDevicesArrayAdapter;
    private ArrayAdapter<String> mNewDevicesArrayAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_device_list);
        setResult(Activity.RESULT_CANCELED);
        // 获取本地蓝牙适配器
        mBtAdapter = BluetoothAdapter.getDefaultAdapter();
        mBtAdapter.enable(); //打开蓝牙
        doDiscovery();  //开始搜索蓝牙设备


        //ListView控件适配器组装
        mPairedDevicesArrayAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1);
        mNewDevicesArrayAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1);
        ListView pairedListView = (ListView)findViewById(R.id.paired_devices);
        pairedListView.setAdapter(mPairedDevicesArrayAdapter);
        pairedListView.setOnItemClickListener(mDeviceClickListener1);
        ListView newDevicesListView = (ListView)findViewById(R.id.new_devices);
        newDevicesListView.setAdapter(mNewDevicesArrayAdapter);
        newDevicesListView.setOnItemClickListener(mDeviceClickListener2);

        //注册广播
        IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
        this.registerReceiver(mReceive,filter);
        filter = new IntentFilter((BluetoothAdapter.ACTION_DISCOVERY_FINISHED));
        this.registerReceiver(mReceive,filter);

        //获得已配对的蓝牙设备
        Set<BluetoothDevice> pairedDevices = mBtAdapter.getBondedDevices();
        if (pairedDevices.size()>0) {
            for (BluetoothDevice device : pairedDevices) {
                mPairedDevicesArrayAdapter.add(device.getName() + "
" + device.getAddress());
            }
        }
        else{
            mPairedDevicesArrayAdapter.add("无已配对设备");
        }

    }

    //蓝牙设备列表的点击响应
    private AdapterView.OnItemClickListener mDeviceClickListener1 = new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            mBtAdapter.cancelDiscovery();
            //获取蓝牙设备的MAC地址返回到主活动
            String info = mPairedDevicesArrayAdapter.getItem(position);
            String address = info.substring(info.length()-17);
            Intent intent = new Intent();
            intent.putExtra(EXTRA_DEVICE_ADDRESS,address);
            setResult(Activity.RESULT_OK,intent);
            finish();



        }
    };
    private AdapterView.OnItemClickListener mDeviceClickListener2 = new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            mBtAdapter.cancelDiscovery();
            //获取蓝牙设备的MAC地址返回到主活动
            String info = mNewDevicesArrayAdapter.getItem(position);
            String address = info.substring(info.length()-17);
            //Toast.makeText(DeviceListActivity.this, address, Toast.LENGTH_SHORT).show();
            Intent intent = new Intent();
            intent.putExtra(EXTRA_DEVICE_ADDRESS,address);
            setResult(Activity.RESULT_OK,intent);
            finish();



        }
    };

    private void doDiscovery(){
        setTitle("扫描中，请稍等……");
        if (mBtAdapter.isDiscovering()){
            mBtAdapter.cancelDiscovery();
        }
        mBtAdapter.startDiscovery();
    }


    @Override
    protected void onDestroy() {
        super.onDestroy();
        // Make sure we're not doing discovery anymore
        if (mBtAdapter != null) {
            mBtAdapter.cancelDiscovery();
        }
        // Unregister broadcast listeners
        this.unregisterReceiver(mReceive);
    }
    //广播监听，当发现新设备时将其添加至列表
    private final BroadcastReceiver mReceive = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            if(BluetoothDevice.ACTION_FOUND.equals(action)){
                BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
                if (device.getBondState()!=BluetoothDevice.BOND_BONDED){
                    mNewDevicesArrayAdapter.add(device.getName()+"
"+device.getAddress());
                }
            }else if(BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)){
                setTitle("请点击设备进行连接：");
                if(mNewDevicesArrayAdapter.getCount() == 0){
                    mNewDevicesArrayAdapter.add("没有搜索到新设备");
                }
            }

        }
    };
}

• BluetoothChatService

package com.example.john.esdc;

import android.annotation.SuppressLint;
import android.app.Notification;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.widget.Toast;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.util.UUID;

/**
 * Created by john on 2017/2/21.
 */

@SuppressLint("NewApi")
public class BluetoothChatService {

    // Unique UUID for this application
    private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
    // Member fields
    private final BluetoothAdapter mAdapter;
    private final Handler mHandler;
    private int mState;
    private ConnectThread mConnectThread;
    private ConnectedThread mConnectedThread;
    private OutputStream mmOutStream=null;

    // Constants that indicate the current connection state
    public static final int STATE_NONE = 0;       // we're doing nothing
    public static final int STATE_LISTEN = 1;     // now listening for incoming connections
    public static final int STATE_CONNECTING = 2; // now initiating an outgoing connection
    public static final int STATE_CONNECTED = 3;  // now connected to a remote device

    //构造函数
    public BluetoothChatService(Context context,Handler handler){
        mAdapter = BluetoothAdapter.getDefaultAdapter();
        mState = STATE_NONE;
        mHandler = handler;
    }
    //设置蓝牙状态并且通过Hander通知UI更新状态
    private synchronized void setState(int state){
        mState = state;
        Message message = new Message();
        message.what = MainActivity.MESSAGE_STATE_CHANGE;
        message.arg1 = state;
        mHandler.sendMessage(message);
    }
    public synchronized int getState(){
        return mState;
    }

    //停止所有线程
    public synchronized void stop() {
        if (mConnectThread != null) {mConnectThread.cancel(); mConnectThread = null;}
        if (mConnectedThread != null) {mConnectedThread.cancel(); mConnectedThread = null;}
        setState(STATE_NONE);
    }
    //连接失败函数，通过UI发出“连接失败”的Toast
    private void connectionFailed() {
        setState(STATE_NONE);
        // Send a failure message back to the Activity
        Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_TOAST);
        Bundle bundle = new Bundle();
        bundle.putString(MainActivity.TOAST, "连接失败");
        msg.setData(bundle);
        mHandler.sendMessage(msg);
    }
    //连接丢失函数，通过UI发出“连接丢失”的Toast
    private void connectionLost() {
        setState(STATE_NONE);

        // Send a failure message back to the Activity
        Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_TOAST);
        Bundle bundle = new Bundle();
        bundle.putString(MainActivity.TOAST, "连接丢失");
        msg.setData(bundle);
        mHandler.sendMessage(msg);
    }
    private void sendFailed(){
        Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_TOAST);
        Bundle bundle = new Bundle();
        bundle.putString(MainActivity.TOAST, "发送失败");
        msg.setData(bundle);
        mHandler.sendMessage(msg);
    }
    //连接函数
    public synchronized void connect(BluetoothDevice device){
        mConnectThread = new ConnectThread(device);
        mConnectThread.start();
        setState(STATE_CONNECTING);
    }
    //连接线程类
    private class ConnectThread extends Thread{
        private final BluetoothSocket mmSocket;
        private final BluetoothDevice mmDevice;
        //构造函数，获得BluetoothDevice，BluetoothSocket
        public ConnectThread(BluetoothDevice device){
            mmDevice = device;
            BluetoothSocket tmp = null;
            try{
                tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
            }catch (IOException e){
                connectionFailed();
            }
            mmSocket = tmp;
        }
        //连接线程的执行逻辑，连接成功后转到ConnectedThraed
        public void run(){
            mAdapter.cancelDiscovery();
            try{
                mmSocket.connect();
            }catch (IOException e){
                connectionFailed();
                try{
                    mmSocket.close();
                }catch (IOException e2){
                }
                return;
            }
            //此处开始connected线程
            connected(mmSocket, mmDevice);

        }
        public void cancel(){
            try{
                mmSocket.close();
            }catch (IOException e){

            }
        }
    }
    //开始已连接线程,发消息通知主活动更新UI
    public synchronized void connected(BluetoothSocket socket,BluetoothDevice device){

        mConnectedThread = new ConnectedThread(socket);
        mConnectedThread.start();

        Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_DEVICE_NAME);
        Bundle bundle = new Bundle();
        bundle.putString(MainActivity.DEVICE_NAME,device.getName());
        msg.setData(bundle);
        mHandler.sendMessage(msg);
        setState(STATE_CONNECTED);
    }
    //已连接线程类
    private class ConnectedThread extends Thread{
        private final BluetoothSocket mmSocket;
        private final InputStream mmInStream;
        //构造函数，获取InputStream，OutputStream
        public ConnectedThread(BluetoothSocket socket){
            mmSocket = socket;
            InputStream tmpIn = null;
            OutputStream tmpOut = null;
            //获取BluetoothSocket的输入输出流
            try{
                tmpIn = socket.getInputStream();
                tmpOut = socket.getOutputStream();
            }catch (IOException e){

            }
            mmInStream = tmpIn;
            mmOutStream = tmpOut;
        }
        //已连接线程的执行逻辑，连接之后持续监听InputStream进行读取
        public void run() {
            while (true){
                try{
                    byte[] arrayOfByte = new byte[1024];
                    int length = 0;
                    length = mmInStream.read(arrayOfByte);
                    Message msg = new Message();
                    msg.what = MainActivity.MESSAGE_READ;
                    msg.obj = new String(arrayOfByte,0,length);
                    mHandler.sendMessage(msg);

                }catch (IOException e){
                    connectionLost();
                    return;
                }
            }
        }

        public void cancel(){
            try{
                mmSocket.close();
            }catch (IOException e){

            }
        }
    }
    //写OutputStream函数，被Send按钮触发sendMessage调用
    public void write(byte[] buffer){
        try{
            mmOutStream.write(buffer);
            mHandler.obtainMessage(MainActivity.MESSAGE_WRITE,-1,-1,buffer).sendToTarget();
        }catch (IOException e){
            return;
        }
    }
}

五.Debug

六.运行效果