学步园

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;
	
	@Override
	protected 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{
		@Override
		public void onServiceConnected(ComponentName name, IBinder service) {
			ibinder = Stub.asInterface(service);
		}
		
		@Override
		public void onServiceDisconnected(ComponentName name) {
			ibinder = null;
			conn = null;
		}
	}
	
	@Override
	protected 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());
	}
	
	@Override
	public 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)
	};
	
	@Override
	public 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();
	}

	@Override
	public String toString() {
		return "Student [id=" + id + ", name=" + name + ", age=" + age + "]";
	}

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

	@Override
	public 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>