android学习-IPC机制之ACtivity绑定Service通信

bindService获得Service的binder对象对服务进行操作

Binder通信过程类似于TCP/IP服务连接过程binder四大架构Server(服务器)，Client(客户端)，ServiceManager(DNS)以及Binder驱动(路由器)

其中Server，Client，ServiceManager运行于用户空间，驱动运行于内核空间。这四个角色的关系和互联网类似：Server是服务器，Client是客户终端，SMgr是域名服务器（DNS），驱动是路由器。

book.java

package com.example.android_binder_testservice;

import android.os.Parcel;
import android.os.Parcelable;

public class Book implements Parcelable {
    private String bookName;
    private String author;
    private int publishDate;

    public Book() {

    }

    public Book(String bookName, String author, int publishDate) {
        super();
        this.bookName = bookName;
        this.author = author;
        this.publishDate = publishDate;
    }

    public String getBookName() {
        return bookName;
    }

    public void setBookName(String bookName) {
        this.bookName = bookName;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public int getPublishDate() {
        return publishDate;
    }

    public void setPublishDate(int publishDate) {
        this.publishDate = publishDate;
    }

    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel out, int flags) {
        out.writeString(bookName);
        out.writeString(author);
        out.writeInt(publishDate);

    }

    public static final Parcelable.Creator<Book> CREATOR = new Creator<Book>() {
        @Override
        public Book[] newArray(int size) {
            return new Book[size];
        }

        @Override
        public Book createFromParcel(android.os.Parcel source) {
            return new Book(source);
        }
    };

    public Book(Parcel in) {
        bookName = in.readString();
        author = in.readString();
        publishDate = in.readInt();
    }
}

上面是一个 实现了parcelable的实体类，就是将book序列化，在putExtra到Service时会被写入内存加快程序速度

mainActivity.java

package com.example.android_binder_testservice;

import android.os.Bundle;
import android.util.Log;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.widget.Button;

public class MainActivity extends Activity {
    Button startServiceButton;// 启动服务按钮
    Button shutDownServiceButton;// 关闭服务按钮
    Button startBindServiceButton;// 启动绑定服务按钮
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        getWidget();
        regiestListener();
    }
    public void getWidget(){
        startServiceButton = (Button) findViewById(R.id.startService);
        startBindServiceButton = (Button) findViewById(R.id.bindService);
        shutDownServiceButton = (Button) findViewById(R.id.stopService);
    }
    public void regiestListener() {
        startServiceButton.setOnClickListener(startService);
        shutDownServiceButton.setOnClickListener(shutdownService);
        startBindServiceButton.setOnClickListener(startBinderService);
    }
    /** 启动服务的事件监听 */
    public Button.OnClickListener startService = new Button.OnClickListener() {
        public void onClick(View view) {
            /** 单击按钮时启动服务 */
            Intent intent = new Intent(MainActivity.this,
                    CountService.class);
            startService(intent);

            Log.v("MainStadyServics", "start Service");
        }
    };
    /** 关闭服务 */
    public Button.OnClickListener shutdownService = new Button.OnClickListener() {
        public void onClick(View view) {
            /** 单击按钮时启动服务 */
            Intent intent = new Intent(MainActivity.this,
                    CountService.class);
            /** 退出Activity是，停止服务 */
            stopService(intent);
            Log.v("MainStadyServics", "shutDown serveice");
        }
    };
    /** 打开绑定服务的Activity */
    public Button.OnClickListener startBinderService = new Button.OnClickListener() {
        public void onClick(View view) {
            /** 单击按钮时启动服务 */
            Intent intent = new Intent(MainActivity.this, UseBrider.class);
            startActivity(intent);
            Log.v("MainStadyServics", "start Binder Service");
        }
    };

}

mainActivity中当使用startService()启动Service时会调用Service的onStartCommand（）

当使用bindService（）则会调用onBind（）方法，可能会觉了看的又看怎么没看到bindService（）这个方法呢

重点在

Intent intent = new Intent(MainActivity.this, UseBrider.class);
startActivity(intent);

继续上代码

UseBrider.java

 /** 通过bindService和unBindSerivce的方式启动和结束服务 */
 public class UseBrider extends FragmentActivity {
     /** 参数设置 */
     CountService countService;

     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(new UseBriderFace(this));

         Intent intent = new Intent(UseBrider.this, CountService.class);
         intent.putExtra("book", new Book("name", "an", 1999));

 　　　　/** 进入Activity开始服务

 　　　　　* conn
 　　　　　*/
         bindService(intent, conn, Context.BIND_AUTO_CREATE);

     }

     private ServiceConnection conn = new ServiceConnection() {
         /*
          * 这个方法会获取到CountService的onBind方法中返回的Binder对象
          * 然后就可以对服务进行某种操作了
          */
         public void onServiceConnected(ComponentName name, IBinder service) {
             // TODO Auto-generated method stub
             countService = ((CountService.ServiceBinder) service).getService();
             countService.callBack();
         }

         /** 无法获取到服务对象时的操作 */
         public void onServiceDisconnected(ComponentName name) {
             // TODO Auto-generated method stub
             countService = null;
         }

     };

     protected void onDestroy() {
         super.onDestroy();
         this.unbindService(conn);
         Log.v("MainStadyServics", "out");
     }
 }

UseBriderFace.java

 public class UseBriderFace extends View{
             /**创建参数*/
         public UseBriderFace(Context context){
             super(context);
         }
         public void onDraw(Canvas canvas){
             canvas.drawColor(Color.WHITE);//画白色背景
                 /**绘制文字*/
             Paint textPaint = new Paint();
             textPaint.setColor(Color.RED);
             textPaint.setTextSize(30);
             canvas.drawText("使用绑定服务", 10, 30, textPaint);
             textPaint.setColor(Color.GREEN);
             textPaint.setTextSize(18);
             canvas.drawText("使用绑定服务后，这个Activity关闭后", 20, 60, textPaint);
             canvas.drawText("绑定的服务也会关闭", 5, 80, textPaint);

         }
     }

UseBriderFace.java类其实就是用java定义的布局可以用xml文件代替

countService.java

 package com.example.android_binder_testservice;

 /**引入包*/
 import android.app.Service;// 服务的类
 import android.os.IBinder;
 import android.os.Parcel;
 import android.os.RemoteException;
 import android.os.Binder;
 import android.content.Intent;
 import android.util.Log;

 /** 计数的服务 */
 public class CountService extends Service {
     private String TAG = CountService.class.getSimpleName();
     /** 创建参数 */
     boolean threadDisable;
     int count;
     Book book;
 /*
  * 当通过bindService()启动CountService时会调用这个方法并返回一个ServiceBinder对象
  * 这个Binder对象封装着一个CountService实例，
  * 客户端就可以通过ServiceBinder对服务端进行一些操作
  */
     public IBinder onBind(Intent intent) {
         Log.i(TAG, "onBind");
         book = intent.getParcelableExtra("book");
         return new ServiceBinder();
     }

     @Override
     public int onStartCommand(Intent intent, int flags, int startId) {
         Log.i(TAG, "onStartCommand");
         return super.onStartCommand(intent, flags, startId);
     }

     @Override
     public boolean onUnbind(Intent intent) {
         Log.i(TAG, "onUnbind");
         return super.onUnbind(intent);
     }

     @Override
     public void onRebind(Intent intent) {
         Log.i(TAG, "onRebind");
         super.onRebind(intent);
     }

     public void onCreate() {
         super.onCreate();
         /** 创建一个线程，每秒计数器加一，并在控制台进行Log输出 */
         new Thread(new Runnable() {
             public void run() {
                 while (!threadDisable) {
                     try {
                         Thread.sleep(1000);
                     } catch (InterruptedException e) {

                     }
                     count++;
                     Log.v("CountService", "Count is" + count);
                 }
             }
         }).start();
         Log.i(TAG, "onCreate");
     }

     public void onDestroy() {
         super.onDestroy();
         /** 服务停止时，终止计数进程 */
         this.threadDisable = true;
         Log.i(TAG, "onDestroy");
     }

     public int getConunt() {
         return count;
     }
     public void callBack(){
         Log.i(TAG, "hello,i am a method of CountService");
     }

     class ServiceBinder extends Binder {
         public CountService getService() {

             return CountService.this;
         }

     }
 }

代码解释有了，想不出来了

源码下载地址：http://git.oschina.net/zwh_9527/Binder