Apparently, I can specify source folders using the source.dir property in build.properties - but what if I want to specify multiple source folders ?
The comments below are from the build.xml file generated by the Android SDK tools:
<!-- The build.properties file can be created by you and is never touched
by the 'android' tool. This is the place to change some of the default property values
used by the Ant rules.
Here are some properties you may want to change/update:
application.package
the name of your application package as defined in the manifest. Used by the
'uninstall' rule.
source.dir
the name of the source directory. Default is 'src'.
out.dir
the name of the output directory. Default is 'bin'.
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 in in Version Control Systems.
-->
Note: I dont care about building in Eclipse - Im setting up automated builds using ant.