Android中单APK应用多进程

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本人博客[原文][Link 1]

Android中，默认一个APK包就对应一个进程，其进程名就为AndroidManifest.xml文件中 指定的package名。我们可以通过Activity, Service, BroadCastReceiver, ContentProvider的android:process属性来实现单APK多进程

但是需要注意进程间内存的 不可见性 。

**实例1**

文件1   MainActivity.java

package  com . lenovo . robin . test ;

import  android . os . Bundle ;

import  android . app . Activity ;

import  android . content . Intent ;

import  android . util . Log ;

import  android . view . Menu ;

import  android . view . MenuItem ;

import  android . support . v4 . app . NavUtils ;

public  class  MainActivity  extends  Activity  \{

static  boolean  iscreated = false ;

final  static  String  TAG = "robin" ;

@Override

public  void  onCreate ( Bundle  savedInstanceState )  \{

super . onCreate ( savedInstanceState );

setContentView ( R . layout . activity\_main );

iscreated = true ;

Log . i ( TAG , "on create() in MainActivity" );

this . startService ( new  Intent ( this , MyService . class ));

文件2  MyService.java

package  com . lenovo . robin . test ;

import  android . app . Service ;

import  android . content . Intent ;

import  android . os . IBinder ;

import  android . util . Log ;

public  class  MyService  extends  Service  \{

String  tag = "robin" ;

@Override

public  void  onCreate ()  \{

Log . i ( tag , "MyService is oncreate" );

@Override

public  int  onStartCommand ( Intent  intent ,  int  flags ,  int  startId )  \{

Log . i ( tag ,  "MainActivity is created: "  \+  MainActivity . iscreated );

return  START\_STICKY ;

@Override

public  void  onDestroy ()  \{

Log . i ( tag , "OnDestory" );

@Override

public  IBinder  onBind ( Intent  arg0 )  \{

return  null ;

文件 3 layout\\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"  >

<TextView

android:layout\_width = "wrap\_content"

android:layout\_height = "wrap\_content"

android:layout\_centerHorizontal = "true"

android:layout\_centerVertical = "true"

android:text = "@string/hello\_world"

tools:context = ".MainActivity"  />

</RelativeLayout>

文件4  AndroidManifest.xml

<manifest  xmlns:android = "http://schemas.android.com/apk/res/android"

package = "com.lenovo.robin.test"

android:versionCode = "1"

android:versionName = "1.0"  >

<uses-sdk

android:minSdkVersion = "8"

android:targetSdkVersion = "15"  />

<application

android:icon = "@drawable/ic\_launcher"

android:label = "@string/app\_name"

android:theme = "@style/AppTheme"  >

<activity

android:name = ".MainActivity"

android:label = "@string/title\_activity\_main"  >

<intent-filter>

</intent-filter>

</activity>

<service

android:name = ".MyService"

android:label = "@string/title\_activity\_main" >

</service>

</application>

</manifest>

文件5  values\\strings.xml

<string  name = "hello\_world" > Hello world! </string>

<string  name = "menu\_settings" > Settings </string>

<string  name = "title\_activity\_main" > MainActivity </string>

</resources>

运行该应用程序

DDMS截图显示的进程如下：

![Android中如何实现单APK多进程 - hubingforever - 民主与科学][Android_APK_ - hubingforever -]

运行打印出的日志如下：

08-12 21:55:32.365: I/robin(25964): on create() in MainActivity

08-12 21:55:32.435: I/robin(25964): MyService is oncreate

08-12 21:55:32.435: I/robin(25964): MainActivity is created: true

我们对 AndroidManifest.xml文件进行修改，以实现当APK应用多进程。

修改后的 AndroidManifest.xml文件如下

<manifest  xmlns:android = "http://schemas.android.com/apk/res/android"

package = "com.lenovo.robin.test"

android:versionCode = "1"

android:versionName = "1.0"  >

<uses-sdk

android:minSdkVersion = "8"

android:targetSdkVersion = "15"  />

<application

android:icon = "@drawable/ic\_launcher"

android:label = "@string/app\_name"

android:theme = "@style/AppTheme"  >

<activity

android:name = ".MainActivity"

android:label = "@string/title\_activity\_main"  >

<intent-filter>

</intent-filter>

</activity>

<service

android:name = ".MyService"

android:label = "@string/title\_activity\_main"

android:process = "com.lenove.robin.test.service" >

</service>

</application>

</manifest>

DDMS截图显示的进程如下：

![Android中如何实现单APK多进程 - hubingforever - 民主与科学][Android_APK_ - hubingforever - 1]

运行打印出的日志如下：

08-11 06:58:56.917: I/robin(10561): on create() in MainActivity

08-11 06:58:57.037: I/robin(10572): MyService is oncreate

08-11 06:58:57.037: I/robin(10572): MainActivity is created:  false

虽然我们在MainActivity的onCreate中把iscreated变量设置为了true,因为进程间内存的不可见性，，所以才会打印日志“ MainActivity is created:  false”。

简单点说就是 每个进程都是运行在不同的虚拟机上，对于不同的进程，他们载入的Class文件虽然名字一样（比如都是 com.lenovo.robin.test.MainActivity ），但是他们其实是加载到了不同的内存地址空间。

com.lenovo.robin.test.MainActivity 中把 iscreated 变量设置为true,它其实只是把当前进程（ com.lenovo.robin.test ）的MainActivity类的iscreated变量的设置为了true,

com.lenove.robin.test.service 进程中的  com.lenovo.robin.test.MainActivity  类和它位于不同的内存地址空间，当然其变量iscreated也位于不同的内存地址空间，自然也不受影响。

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![这里写图片描述][SouthEast]

[http_blog.csdn.net_jiangjunshow]: https://blog.csdn.net/jiangjunshow/article/details/77338485
[Link 1]: http://hubingforever.blog.163.com/blog/static/17104057920126285951877/
[Android_APK_ - hubingforever -]: http://img1.ph.126.net/BS6nl51SKspHti_BO3_Jng==/6597196210494239661.jpg
[Android_APK_ - hubingforever - 1]: http://img9.ph.126.net/ITOZIQq9n0h4dCYmm7h3dg==/6597156628075641089.jpg
[SouthEast]: /images/20220417/0667540c938e4518a878ca9e7a0533d0.png