怎样用AIDL Service 传递复杂数据

大家都知道在Android中通过AIDL可以跨进程调用Service中的数据，网上也有很多实例，但是大部分实例都是关于基本数据类型的远程调用，很少讲到复杂数据的调用，今天我用一个例子来演示一下怎样用AIDL Service 传递复杂数据。

我们分2步开始：

第一步：部署我们的服务端，也就是Service端：

1：在Service端我先自定义2个类型：Person和Pet。因为我们需要跨进程传递Person对象和Pet对象，所以Person类和Pet类都必须实现Parcelable接口，并要求在实现类中定义一个名为CREATER，类型为Parcelable.creator的静态Field。

代码如下：

 package com.example.remoteservice;

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

 public class Person implements Parcelable {
     int id;
     String name;
     String pass;

     public Person() {

     }

     public Person(int id, String name, String pass) {
         this.id = id;
         this.name = name;
         this.pass = pass;
     }

     @Override
     public boolean equals(Object o) {
         if (this == o) {
             return true;
         }
         if (o == null) {
             return false;
         }

         if (getClass() != o.getClass()) {
             return false;
         }
         Person other = (Person) o;

         if (name == null) {
             if (other.name != null) {
                 return false;
             }
         } else if (!name.equals(other.name)) {
             return false;
         }

         if (pass == null) {
             if (other.pass != null) {
                 return false;
             }
         } else if (!pass.equals(other.pass)) {
             return false;
         }

         return true;
     }

     @Override
     public int hashCode() {
         final int prime = 31;
         int result = 1;
         result = prime * result + (name == null ? 0 : name.hashCode());
         result = prime * result + (pass == null ? 0 : pass.hashCode());
         return result;
     }

     @Override
     public int describeContents() {

         return 0;
     }

     @Override
     public void writeToParcel(Parcel arg0, int arg1) {
         arg0.writeInt(id);
         arg0.writeString(name);
         arg0.writeString(pass);
     }

     public static final Parcelable.Creator<Person> CREATOR = new Creator<Person>() {

         @Override
         public Person createFromParcel(Parcel source) {

             return new Person(source.readInt(), source.readString(), source.readString());
         }

         @Override
         public Person[] newArray(int size) {

             return new Person[size];
         }
     };

     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 String getPass() {
         return pass;
     }

     public void setPass(String pass) {
         this.pass = pass;
     }

 }

因为我们会对Person进行比较，所以在Person类中我重写了

public int hashCode() 和 public boolean equals(Object o)方法

 package com.example.remoteservice;

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

 public class Pet implements Parcelable {
     String name;
     float weight;

     public Pet(String name, float weight) {
         this.name = name;
         this.weight = weight;
     }

     public String getName() {
         return name;
     }

     public void setName(String name) {
         this.name = name;
     }

     public float getWeight() {
         return weight;
     }

     public void setWeight(float weight) {
         this.weight = weight;
     }

     @Override
     public int describeContents() {

         return 1;
     }

     @Override
     public void writeToParcel(Parcel dest, int flags) {
         dest.writeString(name);
         dest.writeFloat(weight);

     }

     public static final Parcelable.Creator<Pet> CREATOR = new Creator<Pet>() {

         @Override
         public Pet createFromParcel(Parcel source) {

             return new Pet(source.readString(), source.readFloat());
         }

         @Override
         public Pet[] newArray(int size) {

             return new Pet[size];
         }
     };

     @Override
     public String toString() {

         return "name:" + this.name + ";weight:" + this.weight;
     }

 }

2：创建完自定义类型之后还需要用AIDL来定义它们，Person.aidl和Pet.aidl的代码如下：

 package com.example.remoteservice;
 parcelable Person;

 package com.example.remoteservice;
 parcelable Pet;

3：完成1,2之后就可以使用AIDL定义通信接口了，在这里我定义一个IPet.aidl的接口，代码如下：

 package com.example.remoteservice; //必须导入包
 import com.example.remoteservice.Person; //指定自定义类的位置
 import com.example.remoteservice.Pet;

 interface IPet
 {
 List<Pet> getPets(in Person owner);//这里的in表示Person对象是输入的参数
 }

4：服务端的最后一步就是实现Service了，当然不要忘了注册Service，代码如下：

 package com.example.remoteservice;

 import com.example.remoteservice.IPet.Stub;

 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;

 import android.app.Service;
 import android.content.Intent;
 import android.os.IBinder;
 import android.os.RemoteException;
 import android.util.Log;

 public class RemoteService extends Service {

     private PetBinder petBinder;

     private static Map<Person, List<Pet>> pets = new HashMap<Person, List<Pet>>();
     static {
         ArrayList<Pet> list1 = new ArrayList<Pet>();
         list1.add(new Pet("candy", 2.2f));
         list1.add(new Pet("sandy", 4.2f));
         pets.put(new Person(1, "sun", "sun"), list1);

         ArrayList<Pet> list2 = new ArrayList<Pet>();
         list2.add(new Pet("moon", 5.2f));
         list2.add(new Pet("hony", 6.2f));
         pets.put(new Person(1, "csx", "csx"), list2);

     }

     public class PetBinder extends Stub {// 继承IPet接口中的Stub类，Stub类继承了Binder类,所有PetBinder也间接的继承了Binder类

         @Override
         public List<Pet> getPets(Person owner) throws RemoteException {

             return pets.get(owner);
         }

     }

     @Override
     public IBinder onBind(Intent intent) {

         Log.i("csx", "onBind");
         return petBinder;
     }

     @Override
     public void onCreate() {

         super.onCreate();
         Log.i("csx", "onCreate");
         petBinder = new PetBinder();// 实例化Binder

     }

     @Override
     public boolean onUnbind(Intent intent) {

         Log.i("csx", "onUnbind");
         return super.onUnbind(intent);
     }

     @Override
     public void onDestroy() {

         super.onDestroy();
         Log.i("csx", "onDestroy");
     }

 }

这是我Service端的部署情况（其中MainActivity可以不用去实现，因为我们只提供服务，没有窗口显示）：

第二步：部署客户端：

1.在客户端新建一个包，命名需要和服务端放置aidl文件的包名相同（我这里是com.example.remoteservice），然后把服务端的Person.java,Pet.java,Person.aidl,Pet.aidl,IPet.aidl复制到这个包下面

2.在activity中绑定远程服务进行数据交换，layout布局和activity代码如下：

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:paddingBottom="@dimen/activity_vertical_margin"
     android:paddingLeft="@dimen/activity_horizontal_margin"
     android:paddingRight="@dimen/activity_horizontal_margin"
     android:paddingTop="@dimen/activity_vertical_margin"
     tools:context="com.example.remoteclient.RemoteClient" >

     <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:orientation="vertical" >

         <LinearLayout
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:orientation="horizontal" >

             <EditText
                 android:id="@+id/editText_person"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:layout_gravity="bottom"
                 android:ems="10" >
             </EditText>

             <Button
                 android:id="@+id/button_ok"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:layout_gravity="bottom"
                 android:text="确定" />
         </LinearLayout>

         <ListView
             android:id="@+id/listView_pet"
             android:layout_width="match_parent"
             android:layout_height="wrap_content" >
         </ListView>
     </LinearLayout>

 </RelativeLayout>

 package com.example.remoteclient;

 import android.app.Service;
 import android.content.ComponentName;
 import android.content.Intent;
 import android.content.ServiceConnection;
 import android.os.Bundle;
 import android.os.IBinder;
 import android.os.RemoteException;
 import android.support.v7.app.ActionBarActivity;
 import android.util.Log;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.widget.ArrayAdapter;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.ListView;

 import com.example.remoteservice.IPet;
 import com.example.remoteservice.Person;
 import com.example.remoteservice.Pet;

 import java.util.List;

 public class RemoteClient extends ActionBarActivity {

     public static final String REMOTE_SERVICE_ACTION = "com.example.remoteservice.RemoteService.ACTION";
     EditText editText;
     Button button;
     ListView listView;

     IPet petService;// 声明IPet接口
     List<Pet> pets;
     ServiceConnection conn = new ServiceConnection() {

         @Override
         public void onServiceDisconnected(ComponentName name) {
             Log.i("csx", "onServiceDisconnected");
             conn = null;
         }

         @Override
         public void onServiceConnected(ComponentName name, IBinder service) {
             Log.i("csx", "onServiceConnected");
             petService = IPet.Stub.asInterface(service);// 通过远程服务的Binder实现接口

         }
     };

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.remote_client_layout);
         editText = (EditText) findViewById(R.id.editText_person);
         button = (Button) findViewById(R.id.button_ok);
         listView = (ListView) findViewById(R.id.listView_pet);

         Intent service = new Intent();
         service.setAction(REMOTE_SERVICE_ACTION);

         bindService(service, conn, Service.BIND_AUTO_CREATE);// 绑定远程服务

         button.setOnClickListener(new OnClickListener() {

             @Override
             public void onClick(View v) {
                 String personName = editText.getText().toString();
                 if (personName == null || personName.equals("")) {

                     return;
                 }

                 try {
                     pets = petService.getPets(new Person(1, personName, personName));// 调用远程service的getPets方法
                     updataListView();

                 } catch (RemoteException e) {

                     e.printStackTrace();
                 } catch (NullPointerException e) {
                     e.printStackTrace();
                 }

             }
         });

     }

     public void updataListView() {
         listView.setAdapter(null);

         if (pets == null || pets.isEmpty()) {
             return;

         }
         ArrayAdapter<Pet> adapter = new ArrayAdapter<Pet>(RemoteClient.this,
                 android.R.layout.simple_list_item_1, pets);
         listView.setAdapter(adapter);

     }

     @Override
     protected void onDestroy() {

         unbindService(conn);// 解除绑定
         super.onDestroy();
     }

 }

到此为止所有的工作都完成了，下面我们看一下效果：我在编辑框中输入“csx”，点击确定，就会显示出服务端RemoteService中pets的相应数据。