# Android, C++, C4droid, and makefiles

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mynameisnafe    258
Hello !

Okay here's the deal!

The NativeActivity example that comes with the NDK - awesome! Now I can build an app without dealing with Java.

What I'd like to know is a simple thing, but alas I am still noobing my way around Linux distros, to be honest.

How do I take this makefile, for a single C file, which links to GLES, and turn it into a makefile for n * .cpp and .h files?

[CODE]
all: libcube.so
libcube.so: cube.o
$(CC) -o libcube.so cube.o -shared -lEGL -lGLESv1_CM -lm clean: rm libcube.so cube.o [/CODE] The thing that's got me stuck is the lack of a mention of the NativeActivity.c file For example, I just wanna stick a bunch of stuff from that C file into a header file for now! Any help would be greatly appreciated! Oooh by the by, just to really make you screwface, this makefile came from an example that came with the C4Droid App (Though I've seen it in the NDK) - If I have to compile on C4droid then so be it.. in fact, I'd prefer it - the app that creates apps, I mean, how awesome is that? Many thanks! #### Share this post ##### Link to post ##### Share on other sites frob 44902 Make files are a complete programming language in themselves. There are automatic rules in place that know .o files are generated from their source files. Just add the new .o file to the list of dependencies and the magic should happen. Details for make and how the rules work are [url="http://www.gnu.org/software/make/manual/make.html#Implicit-Rules"]available in the documentation[/url]. #### Share this post ##### Link to post ##### Share on other sites gfxgangsta 806 This is an Android.mk makefile taken from the NATIVE_ACTIVITY.HTML help doc: 8/ Create an Android.mk file in the jni/ directory of your project to describe your native module to the build system. An Android.mk file is essentially a snippet of a GNU Make file. For example: LOCAL_PATH :=$(call my-dir)
include $(CLEAR_VARS) LOCAL_MODULE := my_native_module LOCAL_SRC_FILES := my_native_code.c include$(BUILD_SHARED_LIBRARY)

To add more .c or .cpp files, you can add them to the LOCAL_SRC_FILES section like so:

LOCAL_SRC_FILES := my_native_code.c my_native_code_2.c my_native_code_3.c my_native_code_N.c

OR like so:

LOCAL_SRC_FILES := my_native_code.c \
my_native_code_2.c \
my_native_code_3.c \
my_native_code_N.c

There's also the "wildcard" keyword so you can avoid listing all the files manually:

http://stackoverflow.com/questions/8350878/using-makes-wildcard-function-in-android-mk

Hope this helps!

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mynameisnafe    258
[quote name='gfxgangsta' timestamp='1351272081' post='4994208']
This is an Android.mk makefile taken from the NATIVE_ACTIVITY.HTML help doc:
[/quote]

How did I not go and find that? *faceplam*

Two beaut answers guys thank you!

Hope this style of makefile compiles with C4Droid, I shall try it out!

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mynameisnafe    258
I cant seem to make the magic happen within c4droid, could somebody show me how to extend the makefile i've put above, just to include another .h and .cpp?

I did try on Mint and managed to compile a .cpp and its .h, which was cool however I didnt have a LOCAL_SOURCE_FILES field..

Sorry to be picky / a git.

Thanks!

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