远程服务的绑定

原理图：

1、访问远程服务的原理图

2、AIDL介绍

3、IPC原理图

二、实现步骤

上面的操作(之前的那一篇博客)是一个本地的服务。在开发的时候有可能还会去调用别人应用里面提供好的服务。
远程绑定服务，调用服务里面的方法。
1 编写一个接口，再把接口文件修改为aidl,不能有修饰符。
  如果我们使用了自定义对象需要实现Parcelable接口，还需要定义个一个aidl文件对这个类进行一个描述(Student.aidl).
  编译器就会在gen目录下面生成对应的xx.java文件
2 在服务里面创建一个内部类：extends  Stub 实现未实现的方法。
  生成这个类的对象通过onBind()方法返回。


3 在客户端绑定服务。
  注意：
public void onServiceConnected(ComponentName name, IBinder service) {
// TODO Auto-generated method stub
ibinder = Stub.asInterface(service);
}

三、代码如下：

1、client端

1)main.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical" >       <TextView         android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="学号"        />    <EditText         android:id="@+id/et_no"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        />        <Button         android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="查询1"        android:onClick="query1"        />        <TextView         android:id="@+id/tv_info"        android:layout_width="fill_parent"        android:layout_height="fill_parent"                /></LinearLayout>

2)MainActivity

package com.njupt.client1;import com.njupt.domain.Student;import com.njupt.inter.IStudentQueryService;import com.njupt.inter.IStudentQueryService.Stub;import android.os.Bundle;import android.os.IBinder;import android.os.RemoteException;import android.app.Activity;import android.content.ComponentName;import android.content.Intent;import android.content.ServiceConnection;import android.view.Menu;import android.view.View;import android.widget.EditText;import android.widget.TextView;public class MainActivity extends Activity {private EditText et_no;private TextView tv_info;private MyServiceConnection conn;private IStudentQueryService ibinder;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);et_no = (EditText) findViewById(R.id.et_no);tv_info = (TextView) findViewById(R.id.tv_info);conn = new MyServiceConnection();Intent intent = new Intent();intent.setAction("com.njupt.action.myservice");bindService(intent,conn,BIND_AUTO_CREATE);}private class MyServiceConnection implements ServiceConnection{@Overridepublic void onServiceConnected(ComponentName name, IBinder service) {ibinder = Stub.asInterface(service);}@Overridepublic void onServiceDisconnected(ComponentName name) {ibinder = null;conn = null;}}@Overrideprotected void onDestroy() {super.onDestroy();    unbindService(conn);}public void query1(View v)throws RemoteException{String no = et_no.getText().toString();Student student = ibinder.queryStudent(Integer.parseInt(no));tv_info.setText(student.toString());}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.main, menu);return true;}}

2、server端

这里,server端不需要创建Activity文件

1)MyService

package com.njupt.service;import com.njupt.domain.Student;import com.njupt.inter.IStudentQueryService.Stub;import android.app.Service;import android.content.Intent;import android.os.IBinder;public class MyService extends Service {private StudentBinder ibinder = new StudentBinder();private Student[] students = new Student[]{new Student(1,"刘亦菲",25),new Student(2,"章泽天",21),new Student(3,"allen",21),new Student(4,"刘诗诗",25)};@Overridepublic IBinder onBind(Intent intent) {return ibinder;}private class StudentBinder extends Stub{public Student queryStudent(int no){return query(no);}}private Student query(int no){return students[no - 1];}}

2)IStudentQueryService

package com.njupt.inter;import com.njupt.domain.Student;interface IStudentQueryService {Student queryStudent(int no);}

3)Student

package com.njupt.domain;import android.os.Parcel;import android.os.Parcelable;public class Student implements Parcelable {private int id;private String name;private int age;public int getId() {return id;}public void setId(int id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getAge() {return age;}public void setAge(int age) {this.age = age;}public Student(int id, String name, int age) {super();this.id = id;this.name = name;this.age = age;}public Student() {super();}@Overridepublic String toString() {return "Student [id=" + id + ", name=" + name + ", age=" + age + "]";}@Overridepublic int describeContents() {return 0;}@Overridepublic void writeToParcel(Parcel dest, int flags) {dest.writeInt(id);dest.writeString(name);dest.writeInt(age);}public static final Parcelable.Creator<Student> CREATOR = new Parcelable.Creator<Student>() {public Student createFromParcel(Parcel in) {return new Student(in);}public Student[] newArray(int size) {return new Student[size];}};private Student(Parcel in) {id = in.readInt();name = in.readString();age = in.readInt();}}

4)创建一个Student.aidl文件，并在里面写上以下代码：

package com.njupt.domain;parcelable Student;

并将IStudentQueryService.java文件的后缀名改成.aidl

5)将.aidl文件所在的包由Server端拷一份到Client端

6)AndroidManifest.xml

在清单文件上注册service组件,并暴露服务的接口

<service android:name="com.njupt.service.MyService">          <intent-filter >              <action android:name="com.njupt.action.myservice"/>          </intent-filter>            </service>