在Android的ant中启用`--multi-dex`选项

Question

为gradle构建系统启用multi-dex选项很容易，但我还没有找到如何为ant构建启用此选项的示例。如何存档？

Answer 1

我们有两个选择：

1. 更改DexExecTask [为multi dex引入新参数]，编译ant.jar，使用此jar进行构建。我不喜欢这个选项，因为我们必须为所有团队成员提供更新的ant.jar。
2. 修改项目build.xml文件。我找到了很棒的ant构建文件，它有支持multi-dex的所有修改：https://github.com/ruboto/ruboto-irb/blob/master/build.xml

希望，这有帮助。

Answer 2

我在使用基于Ruboto's build.xml的ant的应用程序中引入了多dex支持（对他们赞不绝口！）。这就是我建议采取的路径。在这种情况下，您不必创建自定义ant jar，只需编辑build.xml并应用https://developer.android.com/tools/building/multidex.html

中的所有非gradle步骤

对于build.xml，如果所有路径都能很好地相互配合，你可能需要查看它们中的一些，并且需要调整ant步骤。

在我的情况下，我还必须生成必须放在第一个生成的dex（默认值）中的类列表，因此应用程序甚至可以在Application的onCreate中加载其他dex时启动。为此，您需要运行脚本mainDexClasses，您可以在构建工具中找到它：

mainDexClasses [--output <output file>] <application path>

Alex Lipov写了很好的帖子。

当您有生成的类列表时，您必须通过添加

指向dx参数中的此列表

<arg value="--main-dex-list="class_list_path" />

执行dx。

值得记住的是，Ruboto的脚本假定只会创建一个额外的dex，这并非总是如此。我生成了两个额外的dexes，所以我实现了添加if exists：

            <if>
                <condition>
                    <available file="${third_dex_path}"/>
                </condition>
                <then>
                    <exec executable="${aapt}" dir="${out.absolute.dir}" failonerror="true">
                        <arg line='add -v "${out.absolute.dir}/${resource.package.file.name}" ${third_dex}'/>
                    </exec> 
                </then>
            </if>

Ant中的multidex支持正在开启！它并不像gradle那么容易，但它是可能的。

更新：我的build.xml（除了与答案无关的部分）：

<!-- Packages the application. Overriden in order to add  "-post-package-resources"" dependency-->
    <target name="-package" depends="-dex, -package-resources, -post-package-resources">
        <!-- only package apk if *not* a library project -->
        <do-only-if-not-library elseText="Library project: do not package apk..." >
            <if condition="${build.is.instrumented}">
                <then>
                    <package-helper>
                        <extra-jars>
                            <!-- Injected from external file -->
                            <jarfile path="${emma.dir}/emma_device.jar" />
                        </extra-jars>
                    </package-helper>
                </then>
                <else>
                    <package-helper />
                </else>
            </if>
        </do-only-if-not-library>
    </target>

    <target name="-post-package-resources">
        <property name="second_dex" value="classes2.dex" />
        <property name="third_dex" value="classes3.dex" />
        <property name="second_dex_path" value="${out.absolute.dir}/${second_dex}" />
        <if>
            <condition>
              <and>
                <available file="${second_dex_path}" />
                <or>
                  <not>
                    <uptodate srcfile="${second_dex_path}" targetfile="${out.absolute.dir}/${resource.package.file.name}" />
                  </not>
                  <uptodate srcfile="${out.absolute.dir}/${resource.package.file.name}" targetfile="${out.absolute.dir}/${resource.package.file.name}.d" />
                </or>
              </and>
            </condition>
            <then>
                <echo>Adding classes2.dex to ${resource.package.file.name}</echo>
                <exec executable="${aapt}" dir="${out.absolute.dir}" failonerror="true">
                    <arg line='add -v "${out.absolute.dir}/${resource.package.file.name}" ${second_dex}'/>
                </exec>
                <if>
                    <condition>
                        <available file="${out.absolute.dir}/classes3.dex"/>
                    </condition>
                    <then>
                        <echo>Adding classes3.dex to ${resource.package.file.name}</echo>
                        <exec executable="${aapt}" dir="${out.absolute.dir}" failonerror="true">
                            <arg line='add -v "${out.absolute.dir}/${resource.package.file.name}" ${third_dex}'/>
                        </exec> 
                    </then>
                </if>
            </then>
        </if>
    </target> 

<!-- builds dex in regular way and if it fails, switches to multidex-->
    <macrodef name="dex-helper">
        <element name="external-libs" optional="yes" />
        <attribute name="nolocals" default="false" />
        <sequential>
            <condition property="verbose.option" value="--verbose" else="">
                <istrue value="${verbose}" />
            </condition>
            <condition property="jumbo.option" value="--force-jumbo" else="">
                <istrue value="${dex.force.jumbo}" />
            </condition>

            <!-- Regular DEX process.  We would prefer to use the Android SDK
                 ANT target, but we need to detect the "use multidex" error.
                 https://android.googlesource.com/platform/sdk/+/tools_r21.1/anttasks/src/com/android/ant/DexExecTask.java
            -->
            <mapper id="pre-dex-mapper" type="glob" from="libs/*.jar" to="bin/dexedLibs/*-dexed.jar"/>

            <apply executable="${dx}" failonerror="true" parallel="false" dest="${out.dexed.absolute.dir}" relative="true">
                        <arg value="--dex" />
                        <arg value="--output" />
                        <targetfile/>
                        <arg line="${jumbo.option}" />
                        <arg line="${verbose.option}" />
                        <fileset dir="." includes="libs/*" />
                        <external-libs />
                        <mapper refid="pre-dex-mapper"/>
            </apply>

            <apply executable="${dx}" resultproperty="dex.merge.result" outputproperty="dex.merge.output" parallel="true">
                <arg value="--dex" />
                <arg value="--output=${intermediate.dex.file}" />
                <arg line="${jumbo.option}" />
                <arg line="${verbose.option}" />
                <path path="${out.dex.input.absolute.dir}"/>
                <path refid="out.dex.jar.input.ref" />
                <external-libs />
            </apply>

            <if>
                <condition>
                    <or>
                        <contains string="${dex.merge.output}" substring="Too many field references"/>
                        <contains string="${dex.merge.output}" substring="Too many method references"/>
                    </or>
                </condition>
                <then>
                    <echo message="Number of field or method references is too big.  Switching to multi-dex build." />
                    <multi-dex-helper>
                        <external-libs>
                        <external-libs/>
                        </external-libs>
                    </multi-dex-helper>
                </then>
                <else>
                    <echo message="${dex.merge.output}"/>
                    <fail status="${dex.merge.result}">
                        <condition>
                            <not>
                                <equals arg1="${dex.merge.result}" arg2="0"/>
                            </not>
                        </condition>
                    </fail>
                </else>
            </if>

      </sequential>
    </macrodef>

    <macrodef name="multi-dex-helper">
        <element name="external-libs" optional="yes" />
        <sequential>
            <property name="mainDexClasses" location="${android.build.tools.dir}/mainDexClasses" />

            <exec executable="${mainDexClasses}" failonerror="true" >
                <arg line="--output ${out.absolute.dir}/classes_to_kepp_in_main_dex"/>
                <arg file="${out.absolute.dir}/proguard/obfuscated.jar"/>
            </exec>
            <echo>Converting compiled files and external libraries into ${out.absolute.dir} (multi-dex)</echo>
            <echo>Dexing ${out.classes.absolute.dir} and ${toString:out.dex.jar.input.ref}</echo>
            <apply executable="${dx}" failonerror="true" parallel="true">
                <arg value="--dex" />
                <arg value="--multi-dex" />
                <arg value="--main-dex-list=${out.absolute.dir}/classes_to_kepp_in_main_dex" />
                <arg value="--output=${out.absolute.dir}" />

                <arg line="${jumbo.option}" />
                <arg line="${verbose.option}" />
                <arg path="${out.absolute.dir}/proguard/obfuscated.jar" />
                <path refid="out.dex.jar.input.ref" />
                <external-libs />
            </apply>
        </sequential>
    </macrodef>

Answer 3

我还在ANT版本中添加了multidex，但是在类* .dex支持方面稍微不同的方式更灵活。

无论如何，我分两个阶段完成：1）让DX输出multidex然后2）使用aapt来包含multidex类。在此发布结束时有一个可选步骤用于生成主类列表，但基本实现没有必要。

这是build.xml中的实现，其中包含以下注释：

... your build script ...
<!-- version-tag: custom -->
<!-- (1) Override -package target to add additional JAR to the apk -->
<property name="multidex-secondary-classes.jar" value="classes-secondary.jar" />
<target name="-package" depends="-dex, -package-resources, -create-multidex-secondary-classes-jar">
    <!-- Copied from SDK/tools/ant/build.xml -->
    <!-- only package apk if *not* a library project -->
    <do-only-if-not-library elseText="Library project: do not package apk..." >
        <if condition="${build.is.instrumented}">
            <then>
                <package-helper>
                    <extra-jars>
                        <!-- Injected from external file -->
                        <jarfile path="${emma.dir}/emma_device.jar" />
                    </extra-jars>
                </package-helper>
            </then>
            <else>
                <!-- We can finesse apkbuilder by putting secondary classes file(s) in a jar file -->
                <if condition="${build.is.multidex}">
                    <then>
                        <package-helper>
                            <extra-jars>
                                <jarfile path="${out.dir}/${multidex-secondary-classes.jar}" />
                            </extra-jars>
                        </package-helper>
                    </then>
                    <else>
                        <package-helper>
                            <extra-jars />
                        </package-helper>
                    </else>
                 </if>
            </else>
        </if>
    </do-only-if-not-library>
</target>

<!-- (2) Create a JAR file of the secondary classes*.dex files -->
<target name="-create-multidex-secondary-classes-jar" if="${build.is.multidex}">
    <jar destfile="${out.dir}/${multidex-secondary-classes.jar}"
         basedir="${out.dir}"
         includes="classes*.dex"
         excludes="classes.dex"
         filesonly="true"
         />
</target>

<!-- Standard import of Android build.xml -->
<import file="${sdk.dir}/tools/ant/build.xml" />

<!-- (3) Replacement of "dex-helper" to support multidex -->
<macrodef name="dex-helper">
    <element name="external-libs" optional="yes" />
    <attribute name="nolocals" default="false" />
    <sequential>
        <!-- sets the primary input for dex. If a pre-dex task sets it to
             something else this has no effect -->
        <property name="out.dex.input.absolute.dir" value="${out.classes.absolute.dir}" />

        <!-- set the secondary dx input: the project (and library) jar files
             If a pre-dex task sets it to something else this has no effect -->
        <if>
            <condition>
                <isreference refid="out.dex.jar.input.ref" />
            </condition>
            <else>
                <path id="out.dex.jar.input.ref">
                    <path refid="project.all.jars.path" />
                </path>
            </else>
        </if>

        <if condition="${build.is.multidex}" >
            <then>
                <if condition="${dex.force.jumbo}" >
                    <else>
                        <fail message="The following assumes dex.force.jumbo is true" />
                    </else>
                </if>
                <apply executable="${dx}" failonerror="true" parallel="true">
                    <arg value="--dex" />
                    <arg value="--force-jumbo" />

                    <!-- Specify a multi-dex APK -->
                    <arg value="--multi-dex" />

                    <!-- For multidex output to a folder -->
                    <arg value="--output" />
                    <arg value="${out.dir}" />

                    <path path="${out.dex.input.absolute.dir}" />
                </apply>
            </then>
            <else>
                <!-- The value from SDK/tools/ant/build.xml -->
                <dex executable="${dx}"
                        output="${intermediate.dex.file}"
                        dexedlibs="${out.dexed.absolute.dir}"
                        nolocals="@{nolocals}"
                        forceJumbo="${dex.force.jumbo}"
                        disableDexMerger="${dex.disable.merger}"
                        verbose="${verbose}">
                    <path path="${out.dex.input.absolute.dir}"/>
                    <path refid="out.dex.jar.input.ref" />
                    <external-libs />
                </dex>
            </else>
        </if>
    </sequential>
</macrodef>

修改（1）替换-package目标以允许将额外的jar传递给ApkBuilder。事实证明，ApkBuilder只是将JAR文件的内容复制到APK中，所以如果我们将类[1-N] .dex放入JAR中，我们就可以让ApkBuilder将这些额外的jar包装到APK中。

（2）使用所有类* .dex构建额外的JAR文件，除了classes.dex，因此支持任意数量的额外classes.dex文件

（3）解决这个事实的问题是＆＃34; dex＆＃34; AntTask不支持任何方式将--multi-dex传递给＆＃34; dx.bat＆＃34;，它知道如何使用它。我查看了dx.bat正在调用的内容并直接在这里添加（修改：michaelbrz在他的脚本中有更好的实现，所以我借了它。谢谢你）

顺便说一句，我们总是运行Proguard（混淆或未混淆）以获得类和方法缩减。这对于生成一个＆＃34;主类＆＃34;非常方便。名单。在我们的案例中，我们添加了Google Play服务并且我们的DEX文件方法限制已经破坏，所以决定将这些类和方法放在次要dex中。从Proguard输出生成该类列表是一个简单的过滤dump.txt：

<property name="multidex-main-dex-list.file"
          value="bin/multidex-main-dex-list.txt" />

<target name="-create-multidex-main-list" if="${build.is.multidex}">
    <delete file="${multidex-main-dex-list.file}" />
    <copy file="${out.dir}/proguard/dump.txt"
          tofile="${multidex-main-dex-list.file}" >
        <filterchain>

            <!-- Convert classes to the right format -->
            <tokenfilter>
                <containsregex
                    pattern="^..Program class..(.*)"
                    replace="\1.class"/>
            </tokenfilter>

            <!-- Exclude Google Play Services -->
            <linecontains negate="true">
                <contains value="com/google/android/gms/"/>
            </linecontains>

        </filterchain>
    </copy>
</target>