How to add a new .cpp file to, and then build, a c++ library for Android?

Question

I'm making a Unity3d plugin for this c++ library for Android. Ive gotten it to work in windows by opening the visual studio project the library makers provided, adding a new .cpp file to it with my API code and building to a dll. I'm wondering now how I can add this new .cpp file to the library and build it for Android. So far I have installed the Android sdk and ndk on a machine with ubuntu and successfully built the original library using ndk-build (as per these instructions) I'm guessing it is not as simple as copying my .cpp file into the folder and building as there are AndroidManifest.xml files and so on.

Answer 1

The AndroidManifest.xml file is not pertinent for an NDK build.

You will need to find the appropriate Android.mk file. You may need to add the file name into the LOCAL_SRC_FILES in that make file, although they may have it set up to compile all the .cpp files in the directory or something more intelligent along those lines. It is, after all, a regular make file.

See here for info on the Android.mk file specifics.

Edit:

I suppose I should add that it would be the LOCAL_SRC_FILES preceding the relevant include $(BUILD_SHARED_LIBRARY) for the library you intend to build. Each make file may contain an arbitrary number of targets, although in the simplest case it's usually one make file to build a library.