android - build.xml 和 project_name.xml 之间的区别

Question

我现在花了几个小时试图了解 Android 的构建过程。

我正在使用适用于 Android 的 IntelliJ Idea（这是一个很棒的工具）。我在 IntelliJ 名称“Hello Android”中打开了一个测试项目。该项目有这个文件名build.xml，代码如下

<?xml version="1.0" encoding="UTF-8"?>
<project name="HelloAndroid" default="help">

    <!-- The local.properties file is created and updated by the 'android' tool.
         It contains the path to the SDK. It should *NOT* be checked into
         Version Control Systems. -->
    <property file="local.properties" />

    <!-- The ant.properties file can be created by you. It is only edited by the
         'android' tool to add properties to it.
         This is the place to change some Ant specific build properties.
         Here are some properties you may want to change/update:

         source.dir
             The name of the source directory. Default is 'src'.
         out.dir
             The name of the output directory. Default is 'bin'.

         For other overridable properties, look at the beginning of the rules
         files in the SDK, at tools/ant/build.xml

         Properties related to the SDK location or the project target should
         be updated using the 'android' tool with the 'update' action.

         This file is an integral part of the build system for your
         application and should be checked into Version Control Systems.

         -->
    <property file="ant.properties" />

    <!-- if sdk.dir was not set from one of the property file, then
         get it from the ANDROID_HOME env var.
         This must be done before we load project.properties since
         the proguard config can use sdk.dir -->
    <property environment="env" />
    <condition property="sdk.dir" value="${env.ANDROID_HOME}">
        <isset property="env.ANDROID_HOME" />
    </condition>

    <!-- The project.properties file is created and updated by the 'android'
         tool, as well as ADT.

         This contains project specific properties such as project target, and library
         dependencies. Lower level build properties are stored in ant.properties
         (or in .classpath for Eclipse projects).

         This file is an integral part of the build system for your
         application and should be checked into Version Control Systems. -->
    <loadproperties srcFile="project.properties" />

    <!-- quick check on sdk.dir -->
    <fail
            message="sdk.dir is missing. Make sure to generate local.properties using 'android update project' or to inject it through the ANDROID_HOME environment variable."
            unless="sdk.dir"
    />

    <!--
        Import per project custom build rules if present at the root of the project.
        This is the place to put custom intermediary targets such as:
            -pre-build
            -pre-compile
            -post-compile (This is typically used for code obfuscation.
                           Compiled code location: ${out.classes.absolute.dir}
                           If this is not done in place, override ${out.dex.input.absolute.dir})
            -post-package
            -post-build
            -pre-clean
    -->
    <import file="custom_rules.xml" optional="true" />

    <!-- Import the actual build file.

         To customize existing targets, there are two options:
         - Customize only one target:
             - copy/paste the target into this file, *before* the
               <import> task.
             - customize it to your needs.
         - Customize the whole content of build.xml
             - copy/paste the content of the rules files (minus the top node)
               into this file, replacing the <import> task.
             - customize to your needs.

         ***********************
         ****** IMPORTANT ******
         ***********************
         In all cases you must update the value of version-tag below to read 'custom' instead of an integer,
         in order to avoid having your file be overridden by tools such as "android update project"
    -->
    <!-- version-tag: 1 -->
    <import file="${sdk.dir}/tools/ant/build.xml" />

</project>

然后我在 IntelliJ Idea Build -> Generate Ant Build中做了以下操作并选择了以下选项

1. 生成多文件 ant build
2. 输出文件名：helloandroid
3. 启用 UI 表单编译
4. 使用项目文件中的 JSDK 定义

这导致创建了三个额外的文件

1. 你好android.properties
2. 你好android.xml
3. module_helloandroid.xml

你好android.properties

path.variable.maven_repository=C\:\\Users\\abc\\.m2\\repository
jdk.home.android_4.1_platform=C\:/Program Files (x86)/Android/android-sdk

你好android.xml

<?xml version="1.0" encoding="UTF-8"?>
<project name="HelloAndroid" default="help">

    <!-- The local.properties file is created and updated by the 'android' tool.
         It contains the path to the SDK. It should *NOT* be checked into
         Version Control Systems. -->
    <property file="local.properties" />

    <!-- The ant.properties file can be created by you. It is only edited by the
         'android' tool to add properties to it.
         This is the place to change some Ant specific build properties.
         Here are some properties you may want to change/update:

         source.dir
             The name of the source directory. Default is 'src'.
         out.dir
             The name of the output directory. Default is 'bin'.

         For other overridable properties, look at the beginning of the rules
         files in the SDK, at tools/ant/build.xml

         Properties related to the SDK location or the project target should
         be updated using the 'android' tool with the 'update' action.

         This file is an integral part of the build system for your
         application and should be checked into Version Control Systems.

         -->
    <property file="ant.properties" />

    <!-- if sdk.dir was not set from one of the property file, then
         get it from the ANDROID_HOME env var.
         This must be done before we load project.properties since
         the proguard config can use sdk.dir -->
    <property environment="env" />
    <condition property="sdk.dir" value="${env.ANDROID_HOME}">
        <isset property="env.ANDROID_HOME" />
    </condition>

    <!-- The project.properties file is created and updated by the 'android'
         tool, as well as ADT.

         This contains project specific properties such as project target, and library
         dependencies. Lower level build properties are stored in ant.properties
         (or in .classpath for Eclipse projects).

         This file is an integral part of the build system for your
         application and should be checked into Version Control Systems. -->
    <loadproperties srcFile="project.properties" />

    <!-- quick check on sdk.dir -->
    <fail
            message="sdk.dir is missing. Make sure to generate local.properties using 'android update project' or to inject it through the ANDROID_HOME environment variable."
            unless="sdk.dir"
    />

    <!--
        Import per project custom build rules if present at the root of the project.
        This is the place to put custom intermediary targets such as:
            -pre-build
            -pre-compile
            -post-compile (This is typically used for code obfuscation.
                           Compiled code location: ${out.classes.absolute.dir}
                           If this is not done in place, override ${out.dex.input.absolute.dir})
            -post-package
            -post-build
            -pre-clean
    -->
    <import file="custom_rules.xml" optional="true" />

    <!-- Import the actual build file.

         To customize existing targets, there are two options:
         - Customize only one target:
             - copy/paste the target into this file, *before* the
               <import> task.
             - customize it to your needs.
         - Customize the whole content of build.xml
             - copy/paste the content of the rules files (minus the top node)
               into this file, replacing the <import> task.
             - customize to your needs.

         ***********************
         ****** IMPORTANT ******
         ***********************
         In all cases you must update the value of version-tag below to read 'custom' instead of an integer,
         in order to avoid having your file be overridden by tools such as "android update project"
    -->
    <!-- version-tag: 1 -->
    <import file="${sdk.dir}/tools/ant/build.xml" />

</project>

module_helloandroid.xml

<copy todir="${helloandroid.output.dir}">
  <fileset dir="${module.helloandroid.basedir}/src">
    <patternset refid="compiler.resources"/>
    <type type="file"/>
    <patternset refid="excluded.from.compilation.helloandroid"/>
  </fileset>
  <fileset dir="${module.helloandroid.basedir}/gen">
    <patternset refid="compiler.resources"/>
    <type type="file"/>
    <patternset refid="excluded.from.compilation.helloandroid"/>
  </fileset>
</copy>

我的问题

1. 为什么我们有不同的 build.xml 和 helloandroid.xml 等两个文件？
2. 这些文件可以在构建过程中使用吗？
3. 我们可以编辑这些文件以添加更多的 Ant 构建脚本吗？
4. 为什么 build.xml 在 处显示错误env.ANDROID_HOME？
5. 什么 helloandroid.xml 显示错误jdk.home.1.6？

Answer 1

1. 构建文件可以包含其他构建文件，这是一种正常做法。您的项目与文件helloandroid.xml完全相同build.xml，您可以修改您喜欢的任何一个并丢弃另一个。该build.xml文件是 Ant 的首选约定。您的属性文件仅用于设置属性，并且模块文件看起来不会被调用，但可能存在，以便您可以包含它并按照它的指定进行文件复制。

2. 是的，只需包括它们。可以使用该helloandroid.properties文件来代替对通用project.properties文件的调用，或者您可以保持原样。

3. 是的，请编辑它们，尽管它们应该足以让您轻松开始。

4. 看起来您的 ANDROID_HOME 环境变量尚未设置。您可以通过 IntelliJ 进行设置，但我建议在您的操作系统级别进行设置。

5. 看起来您的 JAVA_HOME 环境变量尚未设置。您可以通过 IntelliJ 进行设置，但我建议在您的操作系统级别进行设置。