AndroidのService与Activity的及时通信

以前发表的博文一直都是没公布到博客园首页，因为怕高手笑话，但是想了想，如果一起讨论一起学习，不耻下问对自己无疑是更好，收获将更多。

希望各位看官不要喷我。

先看图片：

这里有四个按钮，第一个是绑定服务，绑定后，服务里的线程开始运行；第二个是解除绑定，解除绑定貌似只会回调Service的unBind()方法，所以还是要在服务的unBind()或destroy()方法里结束服务线程；第三个就是获取服务里的数据，并同步到Activity的标题；第三就是停止轮询调用获取服务线程的方法，这样就会停止轮询，你讲看到标题的字不会变化了，但是服务里的线程还在继续，因为还没有解除绑定服务。

这里有一个Activity和一个Service，里面各开一个线程，Activity线程用来刷新标题，Service线程用来改变数据，然后通过绑定服务获取服务的实例，然后就可以调用Service的方法了(笔者yy:要是可以在Activity里调用Service的方法多好啊，拉进了Activity和Service的距离，从此他们不再是交叉线而是螺线线！)

其中设计的知识还是挺多的，特别是多线程通信的内容，在Acitity里面我们需要用线程来更新界面，少不了要用到Handler和Message，接下来看代码，因为公司人都走了，就剩我还在这写博客，很想回家所以写的比较乱。

Activity的代码：

package com.bvin.demo.service;

import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.LinearLayout;

import com.bvin.demo.service.BoundService.LocalBinder;

public class MainActivity extends Activity {
    /** Called when the activity is first created. */
    Intent intent;
    BoundService service;
    boolean isBound;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT,ViewGroup.LayoutParams.WRAP_CONTENT);
     
        LinearLayout layout = new LinearLayout(this);
        layout.setOrientation(LinearLayout.VERTICAL);
        Button btStart = new Button(this);
        btStart.setText("开始绑定");
        Button btStop = new Button(this);
        btStop.setText("解除绑定");
        Button btGet = new Button(this);
        btGet.setText("获取Service的内容");
        Button btEnd = new Button(this);
        btEnd.setText("停止获取");
        layout.addView(btStart, params);
        layout.addView(btStop, params);
        layout.addView(btGet, params); 
        layout.addView(btEnd, params); 
        setContentView(layout);
        intent  = new Intent(this,BoundService.class);
        btStart.setOnClickListener(new View.OnClickListener() {
            
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                MainActivity.this.bindService(intent, conn, Context.BIND_AUTO_CREATE);
            }
        });
        btStop.setOnClickListener(new View.OnClickListener() {
            
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                MainActivity.this.unbindService(conn);
            }
        });
        btGet.setOnClickListener(new View.OnClickListener() {
            
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                handler.post(runnable);
            }
        });
        btEnd.setOnClickListener(new View.OnClickListener() {
            
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                handler.removeCallbacks(runnable);
            }
        });
        
    }
    
    private Handler handler = new Handler(){

        @Override
        public void handleMessage(Message msg) {
            // TODO Auto-generated method stub
            super.handleMessage(msg);
            setTitle(msg.what+"");
        }
        
    };
    
    Runnable runnable = new Runnable(){

        @Override
        public void run() {
            // TODO Auto-generated method stub
            Message msg = new Message();
            msg.what = MainActivity.this.service.getInt();
            handler.sendMessage(msg);
            handler.postDelayed(runnable, 2000);
        }
        
    };
    
    
    
    @Override
    protected void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        unbindService(conn);
    }

    private ServiceConnection conn = new ServiceConnection(){

        @Override
        public void onServiceConnected(ComponentName name, IBinder service) {
            // TODO Auto-generated method stub
            LocalBinder binder = (LocalBinder)service;
            MainActivity.this.service = binder.getService();
            
            
            isBound = true;
        }

        @Override
        public void onServiceDisconnected(ComponentName name) {//连接断开服务里的线程就会摧毁
            // TODO Auto-generated method stub
            isBound = false;
        }
        
    };
}

Service的代码：

package com.bvin.demo.service;

import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.util.Log;

public class BoundService extends Service{

    private Handler handler  = new Handler(){

        @Override
        public void handleMessage(Message msg) {
            // TODO Auto-generated method stub
            super.handleMessage(msg);
        }
        
    };
    
    int x = 0;
    
    private Runnable runable = new Runnable(){

        @Override
        public void run() {
            // TODO Auto-generated method stub
            Log.e("数值", x+"");
            x++;
            handler.postDelayed(runable, 2000);
        }
        
    };
    
    public int getInt(){
        return x;
    }
     
    private Binder binder = new LocalBinder();
    
    @Override
    public IBinder onBind(Intent intent) {
        // TODO Auto-generated method stub
        Log.e("BoundService", "onBind");
        return binder;
    }

    public class LocalBinder extends Binder{
        BoundService getService(){
            return BoundService.this;
        }
    }
    
    @Override
    public void onCreate() {//首次创建才调用
        // TODO Auto-generated method stub
        super.onCreate();
        Log.e("BoundService", "onCreate");
        handler.post(runable);
    }

    @Override
    public void onDestroy() {//final摧毁
        // TODO Auto-generated method stub
        super.onDestroy();
        Log.e("BoundService", "onDestroy");
        //handler.removeCallbacks(runable);
    }

    @Override
    public void onStart(Intent intent, int startId) {//开始，可能调用多次
        // TODO Auto-generated method stub
        super.onStart(intent, startId);
        Log.e("BoundService", "onStart");
    }

    @Override
    public boolean onUnbind(Intent intent) {//接触绑定
        // TODO Auto-generated method stub
        Log.e("BoundService", "onUnbind");
        handler.removeCallbacks(runable);
        return super.onUnbind(intent);
    }

    @Override
    public void onRebind(Intent intent) {//重新绑定
        // TODO Auto-generated method stub
        super.onRebind(intent);
        Log.e("BoundService", "onRebind");
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {//服务开始连接
        // TODO Auto-generated method stub
        Log.e("BoundService", "onStartCommand");
        return super.onStartCommand(intent, flags, startId);
    }

    
    
    
}

记得在Manifest里注册上服务哦！