016_03浅谈远程Service和AIDL

　　 如果需要访问不同进程间service中的数据或者方法，需要使用AIDL(android interface description language)工具，可以通过如下方法： 

        public boolean bindService(Intent intent, ServiceConnection conn, int flags) ； 
        public void unbindService(ServiceConnection conn); 

        intent是跳转到service的intent，conn是与service连接状态的类。如果想要访问service中的数据，可以在onServiceConnected()方法中进行实现。

　　 当开发Service类时，该Service类必须提供一个IBinder onBind(Intent intent)方法，在绑定本地Service的情况下，onBind（Intent intent）方法所返回的Ibinder对象将会传给ServiceConnection对象里onServiceConnected（ComponentName name, IBinder service)方法的service参数，这样访问者就可通过该IBinder对象与service进行通信。

　　如果另外一个进程想访问上图MyService.java中getruntimeinfo()方法

1     public String getruntimeinfo(){
2         String info = "momory usage 5%";
3         return info;
4     }

则需要以下步骤：

1，新建一个interface

1 package com.example.day16_04remoteservicedemo;
2 
3 public interface MyRemoteService {
4      public String forworadgetruntimeinfo();
5 }

2，到源程序目录下找到MyRemoteService.java，直接将后缀名改为.aidl并保存

3，刷新project，可看到eclipse中报错

4，去掉public，保存；可看到在gen下自动生成MyRemoteService.java

5，在MyService.java中新建一个内部类RemoteBinder继承自MyRemoteService.java中的Stub类

1     class RemoteBinder extends  Stub{
2         @Override
3         public String forworadgetruntimeinfo() throws RemoteException {    
4             return getruntimeinfo();
5         }
6     }

 6，在AndroidManifest.xml中配置service

1         <service android:name=".MyService">
2              <intent-filter>
3                     <action android:name="com.cskaoyan.service" />
4              </intent-filter>           
5         </service>

被访问的service源代码如下：

 1 package com.example.day16_04remoteservicedemo;
 2 
 3 import com.example.day16_04remoteservicedemo.MyRemoteService.Stub;
 4 import android.app.Service;
 5 import android.content.Intent;
 6 import android.os.IBinder;
 7 import android.os.RemoteException;
 8  
 9 public class MyService extends Service {
10     IBinder binder ;
11     @Override
12     public IBinder onBind(Intent intent) {
13         // TODO Auto-generated method stub
14         System.out.println("MyService.onBind()");
15         //当且仅当此处返回一个非空的Ibinder对象时，bindservice一端的Connection内的onserviceConnected函数才会被系统call到
16         return  new RemoteBinder();
17     }
18     
19     public String getruntimeinfo(){
20         String info = "momory usage 5%";
21         return info;
22     }
23 
24     @Override
25     public boolean onUnbind(Intent intent) {
26         // TODO Auto-generated method stub
27         System.out.println("MyService.onUnbind()");
28         return super.onUnbind(intent);
29     }
30 
31     @Override
32     public void onRebind(Intent intent) {
33         // TODO Auto-generated method stub
34         super.onRebind(intent);
35         System.out.println("MyService.onRebind()");
36     }
37 
38     @Override
39     public void onCreate() {
40         // TODO Auto-generated method stub
41         super.onCreate();
42         System.out.println("MyService.onCreate()");
43     }
44 
45     @Override
46     public void onDestroy() {
47         // TODO Auto-generated method stub
48         super.onDestroy();
49         System.out.println("MyService.onDestroy()");
50     }
51 
52     class RemoteBinder extends  Stub{
53         @Override
54         public String forworadgetruntimeinfo() throws RemoteException {
55             // TODO Auto-generated method stub
56             return getruntimeinfo();
57         }    
58     }
59 }

MyRemoteService.aidl

1 package com.example.day16_04remoteservicedemo;
2 
3  interface MyRemoteService {
4      String forworadgetruntimeinfo();
5 }
 1 <?xml version="1.0" encoding="utf-8"?>
 2 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
 3     package="com.example.day16_04remoteservicedemo"
 4     android:versionCode="1"
 5     android:versionName="1.0" >
 6 
 7     <uses-sdk
 8         android:minSdkVersion="14"
 9         android:targetSdkVersion="21" />
10 
11     <application
12         android:allowBackup="true"
13         android:icon="@drawable/ic_launcher"
14         android:label="@string/app_name"
15         android:theme="@style/AppTheme" >
16         <service android:name=".MyService">
17             <intent-filter>
18                 <action android:name="com.cskaoyan.service" />
19              </intent-filter>           
20         </service>
21     </application>
22 
23 </manifest>

然后再来写客户端：

将com.example.day16_04remoteservicedemo下的MyRemoteService.aidl直接拷贝过来，放置位置如下图：

最重要的一步是如何在OnServiceConnected方法中得到一个IBinder对象

 1     class MyConnection implements ServiceConnection{
 2 
 3         @Override
 4         public void onServiceConnected(ComponentName name, IBinder service) {
 5             //binder= (Stub) service;不可行    
 6             //因为绑定远程Service的ServiceConnection并不能直接获取Service的OnBind()
 7             //方法返回的对象，它只能返回OnBind()方法所返回的对象的代理
 8             myRemoteService = MyRemoteService.Stub.asInterface(service);
 9             // TODO Auto-generated method stub
10             System.out.println("MainActivity.MyConnection.onServiceConnected()");
11         }

源代码如下：

 1 package com.example.day16_05otherapplication;
 2 
 3 import com.example.day16_04remoteservicedemo.MyRemoteService;
 4 import android.app.Activity;
 5 import android.content.ComponentName;
 6 import android.content.Context;
 7 import android.content.Intent;
 8 import android.content.ServiceConnection;
 9 import android.os.Bundle;
10 import android.os.IBinder;
11 import android.os.RemoteException;
12 import android.view.View;
13 
14 public class MainActivity extends Activity {
15 
16     MyConnection conn;
17     MyRemoteService myRemoteService;
18     
19     @Override
20     protected void onCreate(Bundle savedInstanceState) {
21         super.onCreate(savedInstanceState);
22         setContentView(R.layout.activity_main);
23     }
24     
25     public void bindservice(View v){
26         Intent intent = new Intent();
27         intent.setAction("com.cskaoyan.service");
28         conn=new MyConnection();
29         bindService(intent, conn, Context.BIND_AUTO_CREATE);
30         
31     }
32     public void unbindservice(View v){
33         unbindService(conn);
34         conn=null;    
35     }
36     
37     public void remotecall(View v) throws RemoteException{    
38         System.out.println(myRemoteService.forworadgetruntimeinfo());
39         String info = myRemoteService.forworadgetruntimeinfo();
40         System.out.println("MainActivity.remotecall()"+info);
41     }
42     
43     @Override
44     protected void onDestroy() {
45         // TODO Auto-generated method stub
46         super.onDestroy();
47         if (conn!=null) {
48            unbindService(conn);    
49         }
50     }
51     
52     class MyConnection implements ServiceConnection{
53 
54         @Override
55         public void onServiceConnected(ComponentName name, IBinder service) {
56             //binder= (Stub) service;不可行    
57             //因为绑定远程Service的ServiceConnection并不能直接获取Service的OnBind()
58             //方法返回的对象，它只能返回OnBind()方法所返回的对象的代理
59             myRemoteService = MyRemoteService.Stub.asInterface(service);
60             // TODO Auto-generated method stub
61             System.out.println("MainActivity.MyConnection.onServiceConnected()");
62         }
63 
64         @Override
65         public void onServiceDisconnected(ComponentName name) {
66             // TODO Auto-generated method stub
67             System.out.println("MainActivity.MyConnection.DisConnected()");
68         }    
69     }     
70 }
 1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:paddingBottom="@dimen/activity_vertical_margin"
 6     android:paddingLeft="@dimen/activity_horizontal_margin"
 7     android:paddingRight="@dimen/activity_horizontal_margin"
 8     android:paddingTop="@dimen/activity_vertical_margin"
 9     tools:context="com.example.day16_05otherapplication.MainActivity"
10     android:orientation="vertical" >
11 
12     <TextView
13         android:layout_width="wrap_content"
14         android:layout_height="wrap_content"
15         android:text="@string/hello_world" />
16     
17      <Button
18         android:layout_width="wrap_content"
19         android:layout_height="wrap_content"
20         android:text="绑定服务" 
21         android:onClick="bindservice"/>
22         
23      <Button
24         android:layout_width="wrap_content"
25         android:layout_height="wrap_content"
26         android:text="解除绑定"
27         android:onClick="unbindservice" />
28      <Button
29         android:layout_width="wrap_content"
30         android:layout_height="wrap_content"
31         android:text="调用远程的方法" 
32         android:onClick="remotecall"/>
33 </LinearLayout>

当点击“绑定服务后”，再点击“调用远程的方法”，就可以获取MyService.java中 getruntimeinfo()方法中的String  “momory usage 5%”

物随心转，境由心造，一切烦恼皆由心生。
【推广】 免费学中医，健康全家人
原文地址：https://www.cnblogs.com/woodrow2015/p/4533300.html