Android Service和Activity基于串口蓝牙模块的双向通信【第二篇】

一直以来都想利用手机来控制一些东西,比如电灯,电风扇等家电或者智能小车等.

驱动蓝牙模块可以在Activity中直接调用,也可以在多线程下直接使用,但这样会存在一个缺陷:当你按下手机的Home或者Back键的时候.程序退出了,下次你重新启动软件的时候又需要重新建立蓝牙的链接了.

     为了克服以上问题,我把蓝牙模块的调用放到Service里面使用.首先对Service说明下:(来源于http://tianrui-wang-163-com.iteye.com/blog/983099)

Service介绍
Android中的服务和windows中的服务是类似的东西，服务一般没有用户操作界面，它运行于系统中不容易被用户发觉，可以使用它开发如监控之类的程序。

由于没有可视化界面，Service都是从其它程序组件中启动、停止和控制，这些组件包括其它的Service、Activity和Broadcast Receiver。如果你的应用程序正常且不间断的运行，而不直接依赖于用户输入，Service是你最佳的选择。

Service生命周期

服务常用生命周期回调方法如下：
onCreate() 该方法在服务被创建时调用，该方法只会被调用一次，无论调用多少次startService()或bindService()方法，服务也只被创建一次。
onDestroy()该方法在服务被终止时调用。

Service对象不能自己启动，需要通过某个Activity、Service或者其他Context对象来启动。启动的方法有两种，Context.startService和Context.bindService()。两种方式的生命周期是不同的，具体如下所示。
Context.startService方式的生命周期：
启动时，startService –> onCreate() –> onStart()
停止时，stopService –> onDestroy()
Context.bindService方式的生命周期：
绑定时,bindService  -> onCreate() –> onBind()
解绑定时,unbindService –>onUnbind() –> onDestory()

Service实现
定义一个Service只需要如下两步：

第一步：继承Service类
public class SMSService extends Service { } 这里可以选择要实现的方法
第二步：在AndroidManifest.xml文件中的<application>节点里对服务进行配置:
<service android:name=".SMSService" ”></service>

 

好了,废话少说,下面从我的代码直接开始:

package com.lxx;


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

import android.app.Service;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.IBinder;
import android.util.Log;


public class MyService extends Service{

    public boolean threadFlag = true;
    MyThread myThread;
    CommandReceiver cmdReceiver;//继承自BroadcastReceiver对象，用于得到Activity发送过来的命令

    /**************service 命令*********/
    static final int CMD_STOP_SERVICE = 0x01;
    static final int CMD_SEND_DATA = 0x02;
    static final int CMD_SYSTEM_EXIT =0x03;
    static final int CMD_SHOW_TOAST =0x04;

     private BluetoothAdapter mBluetoothAdapter = null;
     private BluetoothSocket btSocket = null;
     private OutputStream outStream = null;
     private InputStream  inStream = null;
     public  boolean bluetoothFlag  = true;
     private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
     private static String address = "00:19:5D:EE:9B:8F"; // <==要连接的蓝牙设备MAC地址

    @Override
    public IBinder onBind(Intent intent) {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public void onCreate() {
        // TODO Auto-generated method stub
        super.onCreate();

    }



    //前台Activity调用startService时，该方法自动执行
    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        // TODO Auto-generated method stub
        cmdReceiver = new CommandReceiver();
        IntentFilter filter = new IntentFilter();//创建IntentFilter对象
        //注册一个广播，用于接收Activity传送过来的命令，控制Service的行为，如：发送数据，停止服务等
        filter.addAction("android.intent.action.cmd");
        //注册Broadcast Receiver
        registerReceiver(cmdReceiver, filter);
        doJob();//调用方法启动线程
        return super.onStartCommand(intent, flags, startId);

    }



    @Override
    public void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        this.unregisterReceiver(cmdReceiver);//取消注册的CommandReceiver
        threadFlag = false;
        boolean retry = true;
        while(retry){
            try{
                 myThread.join();
                 retry = false;
            }catch(Exception e){
                e.printStackTrace();
            }

        }
    }

    public class MyThread extends Thread{
        @Override
        public void run() {
            // TODO Auto-generated method stub
            super.run();
            connectDevice();//连接蓝牙设备
         while(threadFlag){
             int value = readByte();
            if(value != -1){
                DisplayToast(value + "");
            }

            try{
                Thread.sleep(50);
            }catch(Exception e){
                e.printStackTrace();
            }
         }
       }
    }

    public void doJob(){
         mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        if (mBluetoothAdapter == null) {
            DisplayToast("蓝牙设备不可用，请打开蓝牙！");
            bluetoothFlag  = false;
            return;
        }

        if (!mBluetoothAdapter.isEnabled()) {
            DisplayToast("请打开蓝牙并重新运行程序！");
            bluetoothFlag  = false;
            stopService();
            showToast("请打开蓝牙并重新运行程序！");
            return;
        }
        showToast("搜索到蓝牙设备!");
        threadFlag = true;
        myThread = new MyThread();
        myThread.start();

    }
    public  void connectDevice(){
        DisplayToast("正在尝试连接蓝牙设备，请稍后····");
        BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
        try {
           btSocket = device.createRfcommSocketToServiceRecord(MY_UUID);
        } catch (IOException e) {
            DisplayToast("套接字创建失败！");
            bluetoothFlag = false;
        }
        DisplayToast("成功连接蓝牙设备！");
        mBluetoothAdapter.cancelDiscovery();
        try {
                btSocket.connect();
                DisplayToast("连接成功建立，可以开始操控了!");
                showToast("连接成功建立，可以开始操控了!");
                bluetoothFlag = true;
        } catch (IOException e) {
               try {
                    btSocket.close();
                    bluetoothFlag = false;
                } catch (IOException e2) {
                   DisplayToast("连接没有建立，无法关闭套接字！");
                }
        }

        if(bluetoothFlag){
            try {
                inStream = btSocket.getInputStream();
              } catch (IOException e) {
                  e.printStackTrace();
              } //绑定读接口

              try {
                    outStream = btSocket.getOutputStream();
                } catch (IOException e) {
                    e.printStackTrace();
                } //绑定写接口

        }
    }

    public void sendCmd(byte cmd, int value)//串口发送数据
    {
        if(!bluetoothFlag){
            return;
        }
        byte[] msgBuffer = new byte[5];
          msgBuffer[0] = cmd;
          msgBuffer[1] = (byte)(value >> 0  & 0xff);
          msgBuffer[2] = (byte)(value >> 8  & 0xff);
          msgBuffer[3] = (byte)(value >> 16 & 0xff);
          msgBuffer[4] = (byte)(value >> 24 & 0xff);

          try {
            outStream.write(msgBuffer, 0, 5);
            outStream.flush();
          } catch (IOException e) {
              e.printStackTrace();
          }
    }

    public int readByte(){//return -1 if no data
        int ret = -1;
        if(!bluetoothFlag){
            return ret;
        }
        try {
              ret = inStream.read();
            } catch (IOException e) {
              e.printStackTrace();
            }
        return ret;
    }

    public void stopService(){//停止服务
        threadFlag = false;//停止线程
        stopSelf();//停止服务
    }

    public void showToast(String str){//显示提示信息
        Intent intent = new Intent();
        intent.putExtra("cmd", CMD_SHOW_TOAST);
        intent.putExtra("str", str);
        intent.setAction("android.intent.action.lxx");
        sendBroadcast(intent);
    }

    public void DisplayToast(String str)
    {
        Log.d("Season",str);
    }

     //接收Activity传送过来的命令
    private class CommandReceiver extends BroadcastReceiver{
        @Override
        public void onReceive(Context context, Intent intent) {
            if(intent.getAction().equals("android.intent.action.cmd")){
                int cmd = intent.getIntExtra("cmd", -1);//获取Extra信息
                  if(cmd == CMD_STOP_SERVICE){
                      stopService();
                  }

                  if(cmd == CMD_SEND_DATA)
                  {
                     byte command = intent.getByteExtra("command", (byte) 0);
                     int value =  intent.getIntExtra("value", 0);
                      sendCmd(command,value);
                  }

            }
        }
    }



}

package com.lxx; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.util.UUID; import android.app.Service; import android.bluetooth.BluetoothAdapter; import android.bluetooth.BluetoothDevice; import android.bluetooth.BluetoothSocket; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.os.IBinder; import android.util.Log; public class MyService extends Service{ public boolean threadFlag = true; MyThread myThread; CommandReceiver cmdReceiver;//继承自BroadcastReceiver对象，用于得到Activity发送过来的命令 /**************service 命令*********/ static final int CMD_STOP_SERVICE = 0x01; static final int CMD_SEND_DATA = 0x02; static final int CMD_SYSTEM_EXIT =0x03; static final int CMD_SHOW_TOAST =0x04; private BluetoothAdapter mBluetoothAdapter = null; private BluetoothSocket btSocket = null; private OutputStream outStream = null; private InputStream inStream = null; public boolean bluetoothFlag = true; private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"); private static String address = "00:19:5D:EE:9B:8F"; // <==要连接的蓝牙设备MAC地址 @Override public IBinder onBind(Intent intent) { // TODO Auto-generated method stub return null; } @Override public void onCreate() { // TODO Auto-generated method stub super.onCreate(); } //前台Activity调用startService时，该方法自动执行 @Override public int onStartCommand(Intent intent, int flags, int startId) { // TODO Auto-generated method stub cmdReceiver = new CommandReceiver(); IntentFilter filter = new IntentFilter();//创建IntentFilter对象 //注册一个广播，用于接收Activity传送过来的命令，控制Service的行为，如：发送数据，停止服务等 filter.addAction("android.intent.action.cmd"); //注册Broadcast Receiver registerReceiver(cmdReceiver, filter); doJob();//调用方法启动线程 return super.onStartCommand(intent, flags, startId); } @Override public void onDestroy() { // TODO Auto-generated method stub super.onDestroy(); this.unregisterReceiver(cmdReceiver);//取消注册的CommandReceiver threadFlag = false; boolean retry = true; while(retry){ try{ myThread.join(); retry = false; }catch(Exception e){ e.printStackTrace(); } } } public class MyThread extends Thread{ @Override public void run() { // TODO Auto-generated method stub super.run(); connectDevice();//连接蓝牙设备 while(threadFlag){ int value = readByte(); if(value != -1){ DisplayToast(value + ""); } try{ Thread.sleep(50); }catch(Exception e){ e.printStackTrace(); } } } } public void doJob(){ mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter(); if (mBluetoothAdapter == null) { DisplayToast("蓝牙设备不可用，请打开蓝牙！"); bluetoothFlag = false; return; } if (!mBluetoothAdapter.isEnabled()) { DisplayToast("请打开蓝牙并重新运行程序！"); bluetoothFlag = false; stopService(); showToast("请打开蓝牙并重新运行程序！"); return; } showToast("搜索到蓝牙设备!"); threadFlag = true; myThread = new MyThread(); myThread.start(); } public void connectDevice(){ DisplayToast("正在尝试连接蓝牙设备，请稍后····"); BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address); try { btSocket = device.createRfcommSocketToServiceRecord(MY_UUID); } catch (IOException e) { DisplayToast("套接字创建失败！"); bluetoothFlag = false; } DisplayToast("成功连接蓝牙设备！"); mBluetoothAdapter.cancelDiscovery(); try { btSocket.connect(); DisplayToast("连接成功建立，可以开始操控了!"); showToast("连接成功建立，可以开始操控了!"); bluetoothFlag = true; } catch (IOException e) { try { btSocket.close(); bluetoothFlag = false; } catch (IOException e2) { DisplayToast("连接没有建立，无法关闭套接字！"); } } if(bluetoothFlag){ try { inStream = btSocket.getInputStream(); } catch (IOException e) { e.printStackTrace(); } //绑定读接口 try { outStream = btSocket.getOutputStream(); } catch (IOException e) { e.printStackTrace(); } //绑定写接口 } } public void sendCmd(byte cmd, int value)//串口发送数据 { if(!bluetoothFlag){ return; } byte[] msgBuffer = new byte[5]; msgBuffer[0] = cmd; msgBuffer[1] = (byte)(value >> 0 & 0xff); msgBuffer[2] = (byte)(value >> 8 & 0xff); msgBuffer[3] = (byte)(value >> 16 & 0xff); msgBuffer[4] = (byte)(value >> 24 & 0xff); try { outStream.write(msgBuffer, 0, 5); outStream.flush(); } catch (IOException e) { e.printStackTrace(); } } public int readByte(){//return -1 if no data int ret = -1; if(!bluetoothFlag){ return ret; } try { ret = inStream.read(); } catch (IOException e) { e.printStackTrace(); } return ret; } public void stopService(){//停止服务 threadFlag = false;//停止线程 stopSelf();//停止服务 } public void showToast(String str){//显示提示信息 Intent intent = new Intent(); intent.putExtra("cmd", CMD_SHOW_TOAST); intent.putExtra("str", str); intent.setAction("android.intent.action.lxx"); sendBroadcast(intent); } public void DisplayToast(String str) { Log.d("Season",str); } //接收Activity传送过来的命令 private class CommandReceiver extends BroadcastReceiver{ @Override public void onReceive(Context context, Intent intent) { if(intent.getAction().equals("android.intent.action.cmd")){ int cmd = intent.getIntExtra("cmd", -1);//获取Extra信息 if(cmd == CMD_STOP_SERVICE){ stopService(); } if(cmd == CMD_SEND_DATA) { byte command = intent.getByteExtra("command", (byte) 0); int value = intent.getIntExtra("value", 0); sendCmd(command,value); } } } } }

 

主界面Activity只有一个按钮,就是通过Broadcast来想Service发送数据,Service收到数据进行命令等的解析,然后调用相应的函数,相当于直接调用了Service中的函数.因为Activity和Service是运行在不同的进程中的,两者不能进行直接的通讯,必须通过一个"桥梁"建立起联系才行.

package com.lxx;

import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.os.IBinder;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

public class BroadcastActivity extends Activity {
    /** Called when the activity is first created. */

    TextView myTextView;
    Button sendButton;
    MyReceiver receiver;
    IBinder serviceBinder;
    MyService mService;
    Intent intent;
    int value = 0;

    /**************service 命令*********/
    static final int CMD_STOP_SERVICE = 0x01;
    static final int CMD_SEND_DATA = 0x02;
    static final int CMD_SYSTEM_EXIT =0x03;
    static final int CMD_SHOW_TOAST =0x04;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        myTextView = (TextView)findViewById(R.id.myTextView);
        myTextView.setText("Season");
        sendButton = (Button)findViewById(R.id.sendButton);
        sendButton.setOnClickListener(new SendButtonClickListener());

        intent = new Intent(BroadcastActivity.this,MyService.class);
        startService(intent);
    }


    public class SendButtonClickListener implements OnClickListener{

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            byte command = 45;
            int value = 0x12345;
            sendCmd(command,value);
        }
    }

    @Override
    protected void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();

        if(receiver!=null){
            BroadcastActivity.this.unregisterReceiver(receiver);
        }
    }




    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        receiver = new MyReceiver();
        IntentFilter filter=new IntentFilter();
        filter.addAction("android.intent.action.lxx");
        BroadcastActivity.this.registerReceiver(receiver,filter);
    }

    public void showToast(String str){//显示提示信息
        Toast.makeText(getApplicationContext(), str, Toast.LENGTH_SHORT).show();
    }


    public class MyReceiver extends BroadcastReceiver{
    @Override
    public void onReceive(Context context, Intent intent) {
        // TODO Auto-generated method stub
        if(intent.getAction().equals("android.intent.action.lxx")){
            Bundle bundle = intent.getExtras();
            int cmd = bundle.getInt("cmd");

            if(cmd == CMD_SHOW_TOAST){
                String str = bundle.getString("str");
                showToast(str);
            }

            else if(cmd == CMD_SYSTEM_EXIT){
                System.exit(0);
            }

        }
     }
   }

    public void sendCmd(byte command, int value){
        Intent intent = new Intent();//创建Intent对象
        intent.setAction("android.intent.action.cmd");
        intent.putExtra("cmd", CMD_SEND_DATA);
        intent.putExtra("command", command);
        intent.putExtra("value", value);
        sendBroadcast(intent);//发送广播
    }


}

package com.lxx; import android.app.Activity; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.os.Bundle; import android.os.IBinder; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.TextView; import android.widget.Toast; public class BroadcastActivity extends Activity { /** Called when the activity is first created. */ TextView myTextView; Button sendButton; MyReceiver receiver; IBinder serviceBinder; MyService mService; Intent intent; int value = 0; /**************service 命令*********/ static final int CMD_STOP_SERVICE = 0x01; static final int CMD_SEND_DATA = 0x02; static final int CMD_SYSTEM_EXIT =0x03; static final int CMD_SHOW_TOAST =0x04; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); myTextView = (TextView)findViewById(R.id.myTextView); myTextView.setText("Season"); sendButton = (Button)findViewById(R.id.sendButton); sendButton.setOnClickListener(new SendButtonClickListener()); intent = new Intent(BroadcastActivity.this,MyService.class); startService(intent); } public class SendButtonClickListener implements OnClickListener{ @Override public void onClick(View v) { // TODO Auto-generated method stub byte command = 45; int value = 0x12345; sendCmd(command,value); } } @Override protected void onDestroy() { // TODO Auto-generated method stub super.onDestroy(); if(receiver!=null){ BroadcastActivity.this.unregisterReceiver(receiver); } } @Override protected void onResume() { // TODO Auto-generated method stub super.onResume(); receiver = new MyReceiver(); IntentFilter filter=new IntentFilter(); filter.addAction("android.intent.action.lxx"); BroadcastActivity.this.registerReceiver(receiver,filter); } public void showToast(String str){//显示提示信息 Toast.makeText(getApplicationContext(), str, Toast.LENGTH_SHORT).show(); } public class MyReceiver extends BroadcastReceiver{ @Override public void onReceive(Context context, Intent intent) { // TODO Auto-generated method stub if(intent.getAction().equals("android.intent.action.lxx")){ Bundle bundle = intent.getExtras(); int cmd = bundle.getInt("cmd"); if(cmd == CMD_SHOW_TOAST){ String str = bundle.getString("str"); showToast(str); } else if(cmd == CMD_SYSTEM_EXIT){ System.exit(0); } } } } public void sendCmd(byte command, int value){ Intent intent = new Intent();//创建Intent对象 intent.setAction("android.intent.action.cmd"); intent.putExtra("cmd", CMD_SEND_DATA); intent.putExtra("command", command); intent.putExtra("value", value); sendBroadcast(intent);//发送广播 } }

以下主要对代码部分进行详细的说明:

1.为了方便Activity和Service简历起良好的通信关系,需要在各自发送的数据进行命令的解释,这些命令在两者之间是一致的,能够相互读懂对方发送过来的数据.

/**************service 命令*********/
    static final int CMD_STOP_SERVICE = 0x01;//停止服务
    static final int CMD_SEND_DATA = 0x02;//发送数据
    static final int CMD_SYSTEM_EXIT =0x03;//退出程序
    static final int CMD_SHOW_TOAST =0x04;//界面上显示toast

/**************service 命令*********/ static final int CMD_STOP_SERVICE = 0x01;//停止服务 static final int CMD_SEND_DATA = 0x02;//发送数据 static final int CMD_SYSTEM_EXIT =0x03;//退出程序 static final int CMD_SHOW_TOAST =0x04;//界面上显示toast

2.Service传送数据到Activity:

要接收Broadcast首先的有个Receiver:

//接收Activity传送过来的命令
   private class CommandReceiver extends BroadcastReceiver{
       @Override
       public void onReceive(Context context, Intent intent) {
        if(intent.getAction().equals("android.intent.action.cmd")){
            int cmd = intent.getIntExtra("cmd", -1);//获取Extra信息
                 if(cmd == CMD_STOP_SERVICE){
                  stopService();
                 }

                 if(cmd == CMD_SEND_DATA)
                 {
                 byte command = intent.getByteExtra("command", (byte) 0);
                 int value =  intent.getIntExtra("value", 0);
                  sendCmd(command,value);
                 }

        }
       }
   }

//接收Activity传送过来的命令 private class CommandReceiver extends BroadcastReceiver{ @Override public void onReceive(Context context, Intent intent) { if(intent.getAction().equals("android.intent.action.cmd")){ int cmd = intent.getIntExtra("cmd", -1);//获取Extra信息 if(cmd == CMD_STOP_SERVICE){ stopService(); } if(cmd == CMD_SEND_DATA) { byte command = intent.getByteExtra("command", (byte) 0); int value = intent.getIntExtra("value", 0); sendCmd(command,value); } } } }

为了能够接收到数据,首先得把这个Receiver注册:

public class MyReceiver extends BroadcastReceiver{
    @Override
    public void onReceive(Context context, Intent intent) {
        // TODO Auto-generated method stub
        if(intent.getAction().equals("android.intent.action.lxx")){
            Bundle bundle = intent.getExtras();
            int cmd = bundle.getInt("cmd");

            if(cmd == CMD_SHOW_TOAST){
                String str = bundle.getString("str");
                showToast(str);
            }

            else if(cmd == CMD_SYSTEM_EXIT){
                System.exit(0);
            }

        }
     }
   }

public class MyReceiver extends BroadcastReceiver{ @Override public void onReceive(Context context, Intent intent) { // TODO Auto-generated method stub if(intent.getAction().equals("android.intent.action.lxx")){ Bundle bundle = intent.getExtras(); int cmd = bundle.getInt("cmd"); if(cmd == CMD_SHOW_TOAST){ String str = bundle.getString("str"); showToast(str); } else if(cmd == CMD_SYSTEM_EXIT){ System.exit(0); } } } }

 

其中doJob是启动一个线程,定时的去读取蓝牙串口的数据,然后根据里面的数据解析就可以实现不同的操作了,这个反过来就是外设直接控制手机了.因为这个线程是一直在后台运行着的,只要不结束Service,它就一直保持这与外设串口蓝牙模块的通讯.

public class MyThread extends Thread{
        @Override
        public void run() {
            // TODO Auto-generated method stub
            super.run();
            connectDevice();//连接蓝牙设备
         while(threadFlag){
             int value = readByte();//从蓝牙模块读取一个字节的数据,解释命令用
            if(value != -1){
                DisplayToast(value + "");
            }

            try{
                Thread.sleep(50);
            }catch(Exception e){
                e.printStackTrace();
            }
         }
       }
    }

public class MyThread extends Thread{ @Override public void run() { // TODO Auto-generated method stub super.run(); connectDevice();//连接蓝牙设备 while(threadFlag){ int value = readByte();//从蓝牙模块读取一个字节的数据,解释命令用 if(value != -1){ DisplayToast(value + ""); } try{ Thread.sleep(50); }catch(Exception e){ e.printStackTrace(); } } } }

3.Activity传送数据到Service:

 Activity上有一个按钮,点击一下就可以发送数据到蓝牙串口模块,工作原理是这样的:界面上实现按钮的点击事件

public class SendButtonClickListener implements OnClickListener{

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        byte command = 45;
        int value = 0x12345;
           sendCmd(command,value);
    }
   }

public class SendButtonClickListener implements OnClickListener{ @Override public void onClick(View v) { // TODO Auto-generated method stub byte command = 45; int value = 0x12345; sendCmd(command,value); } }

这里的sendCmd是关键,里面通过建立起一个广播消息,Service里会负责接收他

public void sendCmd(byte command, int value){
        Intent intent = new Intent();//创建Intent对象
        intent.setAction("android.intent.action.cmd");
        intent.putExtra("cmd", CMD_SEND_DATA);
        intent.putExtra("command", command);
        intent.putExtra("value", value);
        sendBroadcast(intent);//发送广播
    }

public void sendCmd(byte command, int value){ Intent intent = new Intent();//创建Intent对象 intent.setAction("android.intent.action.cmd"); intent.putExtra("cmd", CMD_SEND_DATA); intent.putExtra("command", command); intent.putExtra("value", value); sendBroadcast(intent);//发送广播 }

Service中

//前台Activity调用startService时，该方法自动执行
    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        // TODO Auto-generated method stub
        cmdReceiver = new CommandReceiver();
        IntentFilter filter = new IntentFilter();//创建IntentFilter对象
        //注册一个广播，用于接收Activity传送过来的命令，控制Service的行为，如：发送数据，停止服务等
        filter.addAction("android.intent.action.cmd");
        //注册Broadcast Receiver
        registerReceiver(cmdReceiver, filter);
        doJob();//调用方法启动线程
        return super.onStartCommand(intent, flags, startId);

    }

//前台Activity调用startService时，该方法自动执行 @Override public int onStartCommand(Intent intent, int flags, int startId) { // TODO Auto-generated method stub cmdReceiver = new CommandReceiver(); IntentFilter filter = new IntentFilter();//创建IntentFilter对象 //注册一个广播，用于接收Activity传送过来的命令，控制Service的行为，如：发送数据，停止服务等 filter.addAction("android.intent.action.cmd"); //注册Broadcast Receiver registerReceiver(cmdReceiver, filter); doJob();//调用方法启动线程 return super.onStartCommand(intent, flags, startId); }

通过以上步骤就可以建立起蓝牙模块发送数据到Activity,Activity也可以发送数据到蓝牙模块了;

本例子的源码:

http://download.csdn.net/source/3557026 

博文转自：http://blog.csdn.net/cen616899547/article/category/1133607