使用 Ant 打包 Android 应用

http://www.oschina.net/question/54100_30501?sort=default&p=2#answers

通常我们习惯用eclipse来开发Android程序，它会自动帮我们打包当前的应用程序。如果在Navigator视图下，我们可以看到以下几个文件：

在上图中，com包放置的是我们的class文件，classes.dex是class文件经过转换后的可以在dalvik上跑的精简类文件，resources.ap_是经过打包的资源文件，ant.apk就是最终的打包文件。

使用ANT来对应用打包，一般会经过以下几个步骤：

1.用aapt命令生成R.java文件

2.用aidl命令生成相应java文件

3.用javac命令编译java源文件生成class文件

4.用dx.bat将class文件转换成classes.dex文件

5.用aapt命令生成资源包文件resources.ap_

6.用apkbuilder.bat打包资源和classes.dex文件,生成unsigned.apk

7.用jarsinger命令对apk认证,生成signed.apk

为了便于理解和记忆，下面来用一张流程图来说明以上的几个过程：

以上就是整体的流程，下面我们就对其每个部分进行做出详细讲解，把每一个步骤都弄清楚了。

我们需要先熟悉一下每一个步骤所使用到的命令：

1.aapt（Android Asset Packaging Tool）命令，根据资源文件生成R.java文件

参数说明：

-f  强制覆盖已存在的文件。
-m  在-J指定的位置下自动生成相应的包的目录。
-J  指定R.java文件生成的目录。
-S  指定资源目录。
-M  指定清单文件。
-I  引入类库。

注意，我们当前所在的位置是ant项目根目录，所以必要时需要输入很多关于命令的路径，以下示例也是一样。

2.aidl（Android Interface Definition Language）命令，根据.aidl定义文件生成java文件

上面的示例所在位置为com/scott/ant下，根据包中的Person.aidl文件，在gen对应的目录中生成Person.java文件，示例中只是处理单一文件，下文中会讲述如何处理目录中的多个aidl文件。

3.javac（Java Compiler）命令，根据源文件生成对应的class文件

参数说明：

-d <目录>      指定存放生成的类文件的位置
-bootclasspath <路径>     覆盖引导类文件的位置

示例中并没有考虑到引用类路径下面的类库，复杂的情况会在稍后遇到的。

4.dx命令，将class文件转换成.dex文件

以上示例是将bin目录下的class文件转换成classes.dex文件，输出到bin目录，我们也许会用到第三方类库，等一会就会看到。

5.aapt将资源文件打包

参数说明：

-f 强制覆盖

-M 指定Manifest文件

-S 指定资源目录

-A 指定资产目录

-I 指定引入的类库

-F 指定要生成的包

6.apkbuilder命令，根据classes.dex文件和resources.ap_生成为签证的apk包

参数说明：

-rf 参照源文件的目录的结构

7.jarsigner命令，对上面生成的apk包进行签证

在签证的过程中，需要使用到证书文件，需要注意的是最后的release是证书的别名，关于如何创建证书，请看下图：

当然也可以在eclipse里使用ADT提供的图形界面完成以上步骤，选中项目，点击右键，“Android Tools=>Export Signed Application Package”，然后再其中的Keystore selection环节选择“Create new keystore”，然后按照提示填写信息就可以了。

以上是我们使用到的命令，接下来我们就该来分析一下ANT所必须的build.xml：

首先我们需要定义大量的变量属性，用来表示使用到的路径、目录等，如下：

< project name = "ant" default = "release" >

    < property environment = "env" />

    < property name = "appName" value = "${ant.project.name}" />

    < property name = "sdk-folder" value = "${env.ANDROID_SDK_HOME}" />

    < property name = "sdk-platform-folder" value = "${sdk-folder}/platforms/android-8" />

    < property name = "sdk-tools" value = "${sdk-folder}/tools" />

    < property name = "sdk-platform-tools" value = "${sdk-platform-folder}/tools" />


    < property name = "aapt" value = "${sdk-platform-tools}/aapt" />
    < property name = "aidl" value = "${sdk-platform-tools}/aidl" />
    < property name = "dx" value = "${sdk-platform-tools}/dx.bat" />
    < property name = "apkbuilder" value = "${sdk-tools}/apkbuilder.bat" />
    < property name = "jarsigner" value = "${env.JAVA_HOME}/bin/jarsigner" />


    < property name = "android-jar" value = "${sdk-platform-folder}/android.jar" />
    < property name = "android-maps-jar" value = "${sdk-folder}/add-ons/addon_google_apis_google_inc_8/libs/maps.jar" />


    < property name = "framework-aidl" value = "${sdk-platform-folder}/framework.aidl" />


    < property name = "outdir-gen" value = "gen" />

    < property name = "outdir-bin" value = "bin" />


    < property name = "manifest-xml" value = "AndroidManifest.xml" />

    < property name = "resource-dir" value = "res" />
    < property name = "asset-dir" value = "assets" />

    < property name = "srcdir" value = "src" />
    < property name = "srcdir-ospath" value = "${basedir}/${srcdir}" />

    < property name = "external-lib" value = "lib" />
    < property name = "external-lib-ospath" value = "${basedir}/${external-lib}" />


    < property name = "outdir-classes" value = "${outdir-bin}" />
    < property name = "outdir-classes-ospath" value = "${basedir}/${outdir-classes}" />


    < property name = "dex-file" value = "classes.dex" />
    < property name = "dex-path" value = "${outdir-bin}/${dex-file}" />
    < property name = "dex-ospath" value = "${basedir}/${dex-path}" />


    < property name = "resources-package" value = "${outdir-bin}/resources.ap_" />
    < property name = "resources-package-ospath" value = "${basedir}/${resources-package}" />


    < property name = "out-unsigned-package" value = "${outdir-bin}/${appName}-unsigned.apk" />
    < property name = "out-unsigned-package-ospath" value = "${basedir}/${out-unsigned-package}" />


    < property name = "keystore-file" value = "${basedir}/release.keystore" />


    < property name = "out-signed-package" value = "${outdir-bin}/${appName}.apk" />
    < property name = "out-signed-package-ospath" value = "${basedir}/${out-signed-package}" />
        ...
project >

然后，我们分步骤来进行，首先是初始化：

    < target name = "init" >
        < echo >Initializing all output directories... echo >
        < delete dir = "${outdir-bin}" />
        < mkdir dir = "${outdir-bin}" />
        < mkdir dir = "${outdir-classes}" />
    target >

其次是生成R.java文件：

    < target name = "gen-R" depends = "init" >
        < echo >Generating R.java from the resources... echo >
        < exec executable = "${aapt}" failonerror = "true" >
            < arg value = "package" />
            < arg value = "-f" />
            < arg value = "-m" />
            < arg value = "-J" />
            < arg value = "${outdir-gen}" />
            < arg value = "-S" />
            < arg value = "${resource-dir}" />
            < arg value = "-M" />
            < arg value = "${manifest-xml}" />
            < arg value = "-I" />
            < arg value = "${android-jar}" />
        exec >
    target >

接着是aidl生成java源文件：

    < target name = "aidl" depends = "gen-R" >
        < echo >Compiling .aidl into java files... echo >
        < apply executable = "${aidl}" failonerror = "true" >

            < arg value = "-p${framework-aidl}" />

            < arg value = "-I${srcdir}" />

            < arg value = "-o${outdir-gen}" />

            < fileset dir = "${srcdir}" >
                < include name = "**/*.aidl" />
            fileset >
        apply >
    target >

我们指定了一个framework.aidl，里面定义了很多android内置对象，然后我们指定了aidl所在目录和输出目录，组后指定编译后缀为aidl的文件。

接下来是将源文件编译成class文件：

    < target name = "compile" depends = "aidl" >
        < echo >Compiling java source code... echo >
        < javac encoding = "utf-8" target = "1.5" srcdir = "." destdir = "${outdir-classes}" bootclasspath = "${android-jar}" >
            < classpath >
                < fileset dir = "${external-lib}" includes = "*.jar" />
                < filelist >
                    < file name = "${android-maps-jar}" />
                filelist >
            classpath >
        javac >
    target >

如果使用到了第三方类库，我们可以在classpath标签下配置。

接着是将class文件转换成classes.dex：

    < target name = "dex" depends = "compile" >
        < echo >Converting compiled files and external libraries into a .dex file... echo >
        < exec executable = "${dx}" failonerror = "true" >
            < arg value = "--dex" />

            < arg value = "--output=${dex-ospath}" />

            < arg value = "${outdir-classes-ospath}" />
            < arg value = "${external-lib-ospath}" />
        exec >
    target >

就像上面的代码一样，如果使用到第三方类库，可以在最后一参数的形式追加进去。

然后是将资源文件打包：

    < target name = "package-res-and-assets" >
        < echo >Packaging resources and assets... echo >
        < exec executable = "${aapt}" failonerror = "true" >
            < arg value = "package" />
            < arg value = "-f" />
            < arg value = "-M" />
            < arg value = "${manifest-xml}" />
            < arg value = "-S" />
            < arg value = "${resource-dir}" />
            < arg value = "-A" />
            < arg value = "${asset-dir}" />
            < arg value = "-I" />
            < arg value = "${android-jar}" />
            < arg value = "-F" />
            < arg value = "${resources-package}" />
        exec >
    target >

接着是打包成未签证的apk包：

    < target name = "package" depends = "dex, package-res-and-assets" >
        < echo >Packaging unsigned apk for release... echo >
        < exec executable = "${apkbuilder}" failonerror = "true" >
            < arg value = "${out-unsigned-package-ospath}" />
            < arg value = "-u" />
            < arg value = "-z" />
            < arg value = "${resources-package-ospath}" />
            < arg value = "-f" />
            < arg value = "${dex-ospath}" />
            < arg value = "-rf" />
            < arg value = "${srcdir-ospath}" />
        exec >
        < echo >It will need to be signed with jarsigner before being published. echo >
    target >

然后是对apk签证：

    < target name = "jarsigner" depends = "package" >
        < echo >Packaging signed apk for release... echo >
        < exec executable = "${jarsigner}" failonerror = "true" >
            < arg value = "-keystore" />
            < arg value = "${keystore-file}" />
            < arg value = "-storepass" />
            < arg value = "123456" />
            < arg value = "-keypass" />
            < arg value = "123456" />
            < arg value = "-signedjar" />
            < arg value = "${out-signed-package-ospath}" />
            < arg value = "${out-unsigned-package-ospath}" />

            < arg value = "release" />
        exec >
    target >

最后发布：

    < target name = "release" depends = "jarsigner" >

        < delete file = "${out-unsigned-package-ospath}" />
        < echo >APK is released. path:${out-signed-package-ospath} echo >
    target >

这样就完成了build.xml的编辑，eclipse继承了ANT，所以我们可以在eclipse中直接运行，也可以在代码中调用。

首先我们需要下载ANT，然后配置相应的环境变量信息，最后我们这样调用：

Process p = Runtime.getRuntime().exec( "ant.bat -buildfile d:/workspace/ant/build.xml" );
InputStream is = p.getInputStream();
BufferedReader br = new BufferedReader( new InputStreamReader(is));
String line = null ;
while ((line = br.readLine()) != null ) {
    System.out.println(line);
}
System.out.println( "SUCCESS." );

全文完！

原文出处：http://blog.csdn.net/liuhe688/article/details/6679879