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