Android远程服务

一、远程服务主要代码

1.IService.aidl

package com.shz.remoteservice;

interface IService {
    String getTicketInfoById(int id);
}

编译aidl文件自动生成的IService.java文件（存在于gen目录下）

/*
 * This file is auto-generated.  DO NOT MODIFY.
 * Original file: E:\\Code\\Java\\远程服务\\src\\com\\shz\\remoteservice\\IService.aidl
 */
package com.shz.remoteservice;
public interface IService extends android.os.IInterface
{
/** Local-side IPC implementation stub class. */
public static abstract class Stub extends android.os.Binder implements com.shz.remoteservice.IService
{
private static final java.lang.String DESCRIPTOR = "com.shz.remoteservice.IService";
/** Construct the stub at attach it to the interface. */
public Stub()
{
this.attachInterface(this, DESCRIPTOR);
}
/**
 * Cast an IBinder object into an com.shz.remoteservice.IService interface,
 * generating a proxy if needed.
 */
public static com.shz.remoteservice.IService asInterface(android.os.IBinder obj)
{
if ((obj==null)) {
return null;
}
android.os.IInterface iin = obj.queryLocalInterface(DESCRIPTOR);
if (((iin!=null)&&(iin instanceof com.shz.remoteservice.IService))) {
return ((com.shz.remoteservice.IService)iin);
}
return new com.shz.remoteservice.IService.Stub.Proxy(obj);
}
@Override public android.os.IBinder asBinder()
{
return this;
}
@Override public boolean onTransact(int code, android.os.Parcel data, android.os.Parcel reply, int flags) throws android.os.RemoteException
{
switch (code)
{
case INTERFACE_TRANSACTION:
{
reply.writeString(DESCRIPTOR);
return true;
}
case TRANSACTION_getTicketInfoById:
{
data.enforceInterface(DESCRIPTOR);
int _arg0;
_arg0 = data.readInt();
java.lang.String _result = this.getTicketInfoById(_arg0);
reply.writeNoException();
reply.writeString(_result);
return true;
}
}
return super.onTransact(code, data, reply, flags);
}
private static class Proxy implements com.shz.remoteservice.IService
{
private android.os.IBinder mRemote;
Proxy(android.os.IBinder remote)
{
mRemote = remote;
}
@Override public android.os.IBinder asBinder()
{
return mRemote;
}
public java.lang.String getInterfaceDescriptor()
{
return DESCRIPTOR;
}
@Override public java.lang.String getTicketInfoById(int id) throws android.os.RemoteException
{
android.os.Parcel _data = android.os.Parcel.obtain();
android.os.Parcel _reply = android.os.Parcel.obtain();
java.lang.String _result;
try {
_data.writeInterfaceToken(DESCRIPTOR);
_data.writeInt(id);
mRemote.transact(Stub.TRANSACTION_getTicketInfoById, _data, _reply, 0);
_reply.readException();
_result = _reply.readString();
}
finally {
_reply.recycle();
_data.recycle();
}
return _result;
}
}
static final int TRANSACTION_getTicketInfoById = (android.os.IBinder.FIRST_CALL_TRANSACTION + 0);
}
public java.lang.String getTicketInfoById(int id) throws android.os.RemoteException;
}

2.TicketService.java

package com.shz.remoteservice;

import java.util.ArrayList;
import java.util.List;

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

/**
 * 后台服务（组件），提供查询电影票相关信息
 * @author SHZ
 *
 */
public class TicketService extends Service {

    private final static String TAG = "TicketService";
    private List<Ticket> tickets;

    @Override
    public IBinder onBind(Intent intent) {
        Log.i(TAG, "onBind 服务绑定成功");
        // 2.Activity绑定服务成功之后，服务返回给Activity一个IBinder类型的对象，
        // 通过该对象，Activity就可以和服务进行交互了，就像一个代理一样
        return new TicketBinder();
    }

    @Override
    public void onCreate() {
        super.onCreate();
        Log.i(TAG, "onCreate 服务创建成功");
        this.tickets = new ArrayList<Ticket>();
        this.tickets.add(new Ticket(1, "变形金刚4", 103));
        this.tickets.add(new Ticket(2, "窃听风云3", 86));
        this.tickets.add(new Ticket(3, "反腐风暴", 75));
    }

    @Override
    public void onStart(Intent intent, int startId) {
        Log.i(TAG, "onStart 服务启动");
        super.onStart(intent, startId);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.i(TAG, "onStartCommand 服务启动");
        return super.onStartCommand(intent, flags, startId);
    }

    @Override
    public boolean onUnbind(Intent intent) {
        Log.i(TAG, "onUnbind 服务解绑成功");
        return super.onUnbind(intent);
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        Log.i(TAG, "onDestroy 服务销毁成功");
    }

    private Ticket getTicket(int id)
    {
        for(Ticket ticket:this.tickets)
        {
            if(ticket.Id == id)
            {
                return ticket;
            }
        }

        return null;
    }

    /**
     * 服务内部方法：查询电影票信息
     * @param id
     * @return
     */
    public String getTicketInfo(int id)
    {
        Ticket ticket = this.getTicket(id);
        if(ticket == null)
        {
            return "未查询到该电影票信息";
        }
        else
        {
            return ticket.toString();
        }
    }

    /**
     * 服务内部方法（测试用，没有意义）：更新电影票价格
     * @param id
     * @param newPrice
     */
    public void updateTicketPrice(int id, float newPrice)
    {
        Ticket ticket = this.getTicket(id);
        if(ticket != null)
        {
            ticket.Price = newPrice;
        }
    }

    /**
     * 自定义一个代理类，继承Binder并实现IService接口。
     * 服务会返回该类的一个实例给调用者，调用者可通过该实例调用相应的类方法
     * @author SHZ
     *
     */
    private class TicketBinder extends IService.Stub
    {
        /**
         * 实现IService接口中的方法，调用服务内部的方法，这样调用服务的Activity就可以获取电影票信息了
         */
        @Override
        public String getTicketInfoById(int id) {
            return getTicketInfo(id);
        }

        /**
         * 由于该方法并未在IService接口中定义，故调用者无法使用该方法
         * @param id
         * @param newPrice
         */
        public void updateTicketPrice(int id,float newPrice)
        {
            updateTicketPrice(id, newPrice);
        }

    }

}

3.Ticket.java(实体类)

package com.shz.remoteservice;

public class Ticket {
    public int Id;
    public String Name;
    public float Price;

    public Ticket(int id, String name, float price) {
        Id = id;
        Name = name;
        Price = price;
    }

    @Override
    public String toString() {
        return "您查询的电影是："+this.Name+"，票价为："+this.Price;
    }
}

4.清单配置文件AndroidManifest.xml

<service android:name="com.shz.remoteservice.TicketService">
            <intent-filter>
                <!-- 如果用于远程服务，则需指定action -->
                <action android:name="com.shz.TICKETSERVICE"/>
            </intent-filter>
        </service>

二、调用远程服务的代码

1.把远程服务工程里面的IService.aidl文件（包括包名）拷贝到调用者的工程中

2.调用代码

package com.shz.callremoteservice;

import android.app.Activity;
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.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import com.shz.remoteservice.IService;

public class MainActivity extends Activity {

    private TicketServiceConnection conn;
    private IService ticketBinder;
    private EditText txtTicketId;
    private TextView lblTicketInfo;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        txtTicketId = (EditText) findViewById(R.id.txtTicketId);
        lblTicketInfo = (TextView) findViewById(R.id.lblTicketInfo);

    }

    private class TicketServiceConnection implements ServiceConnection
    {

        @Override
        public void onServiceConnected(ComponentName name, IBinder service) {
            // 2.绑定服务成功之后，后台服务会返回IBinder类型的 service 对象，通过该对象可以间接调用后台服务的方法
            ticketBinder = IService.Stub.asInterface(service);
        }

        @Override
        public void onServiceDisconnected(ComponentName name) {

        }

    }

    /**
     * 绑定服务
     * @param view
     */
    public void bindService(View view) {
        Intent service = new Intent();
        service.setAction("com.shz.TICKETSERVICE");    // 通过action指定要调用的服务
        // 1.绑定服务
        // service：服务意图
        // new TicketServiceConnection()：与后台服务连接的对象，接收后台服务信息
        // BIND_AUTO_CREATE：如果服务没有被创建，则自动创建并绑定
        conn = new TicketServiceConnection();
        bindService(service, conn, BIND_AUTO_CREATE);
    }

    @Override
    protected void onDestroy() {
        try {
            unbindService(conn);
        } catch (Exception e) {
        }
        super.onDestroy();
    }

    public void callServiceMethod(View view) {
        if(this.ticketBinder == null)
        {
            Toast.makeText(this, "请先绑定服务", 1).show();
        }
        else
        {
            String strTicketId = this.txtTicketId.getText().toString().trim();
            if(TextUtils.isEmpty(strTicketId))
            {
                Toast.makeText(this, "请输入电影票Id", 1).show();
                return;
            }

            try {
                // 3.调用IBinder对象的方法
                String ticketInfo = this.ticketBinder.getTicketInfoById(Integer.parseInt(strTicketId));
                this.lblTicketInfo.setText(ticketInfo);
            } catch (NumberFormatException e) {
                e.printStackTrace();
            } catch (RemoteException e) {
                e.printStackTrace();
            }
        }
    }

}

3.前台UI布局代码

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.shz.localservice.MainActivity"
    tools:ignore="MergeRootFrame" >

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="bindService"
        android:text="绑定服务" />

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="请输入电影票Id"
        android:id="@+id/txtTicketId"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="callServiceMethod"
        android:text="查询" />

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/lblTicketInfo"
        android:textColor="#ff0000"/>

</LinearLayout>

调用服务前必须先绑定服务（当然了，远程服务必须首先启动起来）

调用结果截图：