ANDROID_MARS学习笔记_S01原始版_019_SERVICE之Transact

一、代码
1.xml
(1)activity_main.xml

<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.transact.MainActivity" >

    <Button
        android:id="@+id/btn1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="绑定" />
     <Button
        android:id="@+id/btn2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="发送请求" 
        android:layout_below="@id/btn1"/>

</RelativeLayout>

(2)AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.transact"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <service android:name=".ThirdService"></service>
    </application>

</manifest>

2.java
(1)MainActivity.java

package com.transact;

import android.app.Activity;
import android.content.ComponentName;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Binder;
import android.os.Bundle;
import android.os.IBinder;
import android.os.Parcel;
import android.os.RemoteException;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity {

    private Button btn1,btn2;
    private Binder binder;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        btn1 = (Button) findViewById(R.id.btn1);
        btn2 = (Button) findViewById(R.id.btn2);
        btn1.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent();
                intent.setClass(MainActivity.this, ThirdService.class);
                bindService(intent, conn, BIND_AUTO_CREATE);
            }
        });
        
        btn2.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                Parcel data = Parcel.obtain();
                Parcel reply = Parcel.obtain();
                data.writeString("data from activity");
                try {
                    //Transact()会等待service的onTransact()方法往reply写数据，service的onTransact()执行完后会返回这里
                    binder.transact(0, data, reply, 0);
                    System.out.println("activity's replya data -->"+reply.readString());
                } catch (RemoteException e) {
                    e.printStackTrace();
                }
            }
        });
    }
    
    ServiceConnection conn = new ServiceConnection() {
        @Override
        public void onServiceDisconnected(ComponentName name) {
            
        }
        
        @Override
        public void onServiceConnected(ComponentName name, IBinder service) {
            MainActivity.this.binder = (Binder) service;
        }
    };
}

(2)ThirdService.java

package com.transact;

import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.os.Parcel;
import android.os.RemoteException;

public class ThirdService extends Service {

    @Override
    public IBinder onBind(Intent intent) {
        return new MyBinder();
    }

    class MyBinder extends Binder {
        @Override
        protected boolean onTransact(int code, Parcel data, Parcel reply,
                int flags) throws RemoteException {
            System.out.println("code---->"+code);
            System.out.println("flags---->"+flags);
            System.out.println("data---->"+data.readString());
            reply.writeString("add data from thirdService");
            return super.onTransact(code, data, reply, flags);
        }
    }
}