Android - How do I dynamically set the package name at build time for an Open-source project?

Question

I'm working on an Open-source project. As it is intended that anyone can download the source and build it themselves, I do not want to hard-code the package name anywhere - including the directory structure.

I use ant for building. Apparently I can modify build.xml, but I believe this is overwritten by android update. Whatever is used will be committed to the Git repo, and it should not be too complicated.

Currently the process to build the code straight from the Git repo is fairly simple. Here's an excerpt from the README file:

$ cd ~/src/isokeys/IsoKeys
$ android list targets # I build against API level 10.
$ android update project --name IsoKeys --target 1 --path ./ # Only needed first time.
$ ant debug && adb -d install -r bin/IsoKeys-debug.apk

To me, it makes sense to put the package name in local.properties, because this is .gitignore'd. As the package name won't be anywhere else, the build will fail without doing this. So there needs to be at least 1 extra step in the README, but I want to keep it to a minimum.

Edit: Of course, another requirement is that diffs make sense - which they don't if you manually rename the package name.

Answer 1

I did something similar (but not for this reason) which required updating the manifest at build time. The way I accomplished this was by making a second AndroidManifest and putting it under a directory named config. So in config/AndroidManifest you could have something like this:

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="@CONFIG.APP_PACKAGE_NAME@"
      android:versionCode="@CONFIG.APP_VERSION_CODE@"
      android:versionName="@CONFIG.APP_VERSION@">


<!-- EVERYTHING ELSE GOES HERE -->


</manifest>

Then you can use the regular bare bones build.xml ant script with just a few modifications (no need to copy the whole script from the android build system as they added some hooks for you to use without reinventing the wheel). The build script should be reading local.properties by default, but if not add (or uncomment) a line like this:

<property file="local.properties" />

In your build script you should see a task called "-pre-build", change it like this:

<target name="-pre-build">
     <copy file="config/AndroidManifest.xml" todir="." overwrite="true" encoding="utf-8">
       <filterset>
          <filter token="CONFIG.APP_PACKAGE_NAME" value="${app.packagename}" />
          <filter token="CONFIG.APP_VERSION" value="${app.version}" />
          <filter token="CONFIG.APP_VERSION_CODE" value="${app.versioncode}" />
       </filterset>
     </copy>           
</target>

Then your local.properties file you would put the package name, version name/code like so:

app.version=1.0
app.versioncode=1
app.packagename=com.mypackage.name

Now you just need to make sure in your manifest that you fully qualify all of your activities/services/broadcast listeners etc.. That means you always specify the full package of your source code. If you want the package for your own source code to be dynamic you could replace out each of the prefixes to each class.. But that seems kind of silly.. It is easy enough to package your code up under your own package name and they can use it from any project by simply including the source or a jar in their project.

-- UPDATE -- Oh and one other thing you can do to notify the user that they must define a package name is use the fail tag in your build xml like this:

<fail message="app.packagename is missing. This must be defined in your local.properties file" unless="app.packagename" />

Put this after the line which reads the local.properties file

Answer 2

With thanks to Matt Wolfe for his help, I'm posting a partial answer with my efforts so far.

I noticed that the default barebones build.xml would also import custom_rules.xml:

<import file="custom_rules.xml" optional="true" />

So I created this file and started tinkering. This is what I have come up with so far:

<?xml version="1.0" encoding="UTF-8"?>
<project name="custom_rules" default="debug">
    <target name="-pre-build">
        <fail message="Please define app.packagename in your local.properties file." unless="app.packagename" />
        <taskdef resource="net/sf/antcontrib/antcontrib.properties">
            <classpath>
                <pathelement location="/usr/share/java/ant-contrib.jar"/>
            </classpath>
        </taskdef>
        <!-- How do I check for propertyregex?
        <fail message="Depends on ant-contrib's propertyregex for app.packagename.path." unless="propertyregex" />
        -->
        <propertyregex property="app.packagename.path"
            input="${app.packagename}/"
            regexp="\."
            replace="/"
            global="true"
        />
        <copy todir="build/" overwrite="true" encoding="utf-8">
            <fileset dir="./">
                <include name="AndroidManifest.xml" />
                <include name="res/**" />
                <include name="lib/**" />
            </fileset>
            <filterset>
                <filter token="CONFIG.APP_PACKAGE_NAME" value="${app.packagename}" />
            </filterset>
        </copy>
        <copy todir="build/src/${app.packagename.path}" overwrite="true" encoding="utf-8">
            <fileset dir="./src/isokeys/">
                <include name="**" />
            </fileset>
            <filterset>
                <filter token="CONFIG.APP_PACKAGE_NAME" value="${app.packagename}" />
            </filterset>
        </copy>
    </target>
    <target name="-pre-clean" description="Removes output files created by -pre-build.">
        <delete file="build/AndroidManifest.xml" verbose="${verbose}" />
        <delete dir="build/res/" verbose="${verbose}" />
        <delete dir="build/lib/" verbose="${verbose}" />
        <delete dir="build/src/" verbose="${verbose}" />
    </target>
    <!-- NOW CHANGE DIRECTORY TO build/ BEFORE HANDING BACK OVER TO build.xml!!! -->
</project>

This sets everything up in build/ (which has the added bonus of keeping things neat and tidy), now the intention is for the sdk tools build.xml to run from this build/ directory. However, I can't find any way of cd'ing.

Answer 3

Easiest way might be replace the package name as late as possible. This way, you don't even have to touch your code. There is a nice article named Renaming the Android Manifest package(http://www.piwai.info/renaming-android-manifest-package/). Summary:

• You can use aapt --rename-manifest-package to modify the package name

• Alternatively, if you want package name replacement to be a part of the ant build process, you can override the -package-resources target:

  • copy the -package-resources target from SDK's build.xml
  • add manifestpackage parameter