Android – multiple custom versions of the same app

What I did for something similar to this is to just use an antlib task and then go through all java and xml files to replace my old package string to the new package string. It didn't matter if the files were not in the correct src paths according to the package. Just doing a regex replace for all the files was enough for me to get this working...

For example to replace it in all your java files under the src directory:

 <replaceregexp flags="g" byline="false">
    <regexp pattern="old.package.string" /> 
    <substitution expression="new.package.string" />
    <fileset dir="src" includes="**/*.java" /> 
 </replaceregexp>

The linked-to solution does not have to be done by hand. Bear in mind that the package attribute in the <manifest> element does not have to be where the code resides, so long as you spell out the fully-qualified classes elsewhere in the manifest (e.g., activity android:name="com.commonsware.android.MyActivity" rather than activity android:name=".MyActivity"). Script your manifest change and use Ant to build a new APK. AFAIK, that should work.

I wound up with a script that patches the sources; patching the source sounds risky, but in presence of version control the risk is acceptable.

So I made one version, committed the source, made the other version, committed the source, and looking at diffs wrote a patching script in Python.

I am not sure if it is the best solution. (And the code misses some os.path.joins)

The heart of the script is the following function:

# In the file 'fname',
# find the text matching "before oldtext after" (all occurrences) and
# replace 'oldtext' with 'newtext' (all occurrences).
# If 'mandatory' is true, raise an exception if no replacements were made.
def fileReplace(fname,before,newtext,after,mandatory=True):
    with open(fname, 'r+') as f:
    read_data = f.read()
    pattern = r"("+re.escape(before)+r")\w+("+re.escape(after)+r")"
    replacement = r"\1"+newtext+r"\2"
    new_data,replacements_made = re.subn(pattern,replacement,read_data,flags=re.MULTILINE)
    if replacements_made and really:
        f.seek(0)
        f.truncate()
        f.write(new_data)
        if verbose:
            print "patching ",fname," (",replacements_made," occurrence", "s" if 1!=replacements_made else "",")"
    elif replacements_made:
        print fname,":"
        print new_data
    elif mandatory:
        raise Exception("cannot patch the file: "+fname)

And you may find the following one of use:

# Change the application resource package name everywhere in the src/ tree.
# Yes, this changes the java files. We hope that if something goes wrong,
# the version control will save us.
def patchResourcePackageNameInSrc(pname):
    for root, dirs, files in os.walk('src'):
    if '.svn' in dirs:
        dirs.remove('.svn')
    for fname in files:
        fileReplace(os.path.join(root,fname),"import com.xyz.",pname,".R;",mandatory=False)

There is also a function that copies assets from x-assets-cfgname to assets (earlier it turned out that for me it is more convenient to have a subdirectory in assets).

def copyAssets(vname,force=False):
    assets_source = "x-assets-"+vname+"/xxx"
    assets_target = "assets/xxx"
    if not os.path.exists(assets_source):
        raise Exception("Invalid variant name: "+vname+" (the assets directory "+assets_source+" does not exist)")
    if os.path.exists(assets_target+"/.svn"):
        raise Exception("The assets directory must not be under version control! "+assets_target+"/.svn exists!")
    if os.path.exists(assets_target):
        shutil.rmtree(assets_target)
    shutil.copytree(assets_source, assets_target, ignore=shutil.ignore_patterns('.svn'))

Well, you get the idea. Now you can write your own script.