How to set up JNI sub directories in Android Studio

Question

Let's say we got codes with structure as bellow

src/
├── androidTest
├── app.iml
├── build.gradle
├── main
│   ├── AndroidManifest.xml
│   ├── java
│   ├── jni
│   │   ├── common
│   │   │   ├── inc
│   │   │   │   ├── common.h
│   │   │   │   ├── ...
│   │   │   └── src
│   │   │       ├── common.cc
│   │   │       ├── ...
│   │   └── native-media.cc
│   └── res
├── proguard-rules.pro
└── test

I want to tell Gradle all the sources in main/jni should be compiled. If I just leave it, AS(Android Studio) will use all the files in jni directory to compile. But if there's some sub directories, like common/inc and common/src here, AS will get confused.

I googled a lot, but all the ways I found does not work.(e.g. Gradle-experimental, actually Android Studio will complain and strike if I follow that.)

So, what's the right way to talk about JNI directories with Gradle, as if I'm talking with CMake or GNUMake ...

score 0 · Accepted Answer · edited May 23 '17 at 12:31

0

AS will by default compile all C/C++ files under jni directory. If you need more control, either use the experimental plugin, or disable the built-in task and run ndk-build, see define LOCAL_SRC_FILES in ndk{} DSL for example.

edited May 23 '17 at 12:31

Community

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answered Apr 12 '16 at 15:16

Alex Cohn

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Seems like the recent version of Visual Studio and experimental Gradle changed a lot. – Galaxy Apr 14 '16 at 13:03
*Android Studio* you mean, don't you? – Alex Cohn Apr 14 '16 at 14:11
Yes, Android Studio 2.0 – Galaxy Apr 15 '16 at 06:37
No, AS 2.0 changed nothing; all credit goes to the experimental gradle plugin – Alex Cohn Apr 16 '16 at 15:59

score 0 · Answer 2 · answered Jun 16 '16 at 04:19

Android Studio gradle-experimental plugin uses ${app}/src/main/jni as default for native code, and the processing is recursive: all sub-directories will be included to build native shared lib. If there is some specific file(s) you do not want, you could try "exclude" as in:
https://github.com/googlesamples/vulkan-basic-samples/blob/master/LunarGSamples/Demos/Hologram/android/build.gradle

Note that exclude is for file name, does not matter in which directory it sits or having multiple file of the same name. In the above link, it also includes source code from other directories NOT inside "jni" folder.

You may also see this example:
https://github.com/googlesamples/android-ndk/tree/master/Teapot/app/src/main/jni it builds and runs, have sub-directory under jni too, but does not use "exclude".

Your issue might be something else, Android Studio could handle nested directories. If you could add a ling to your code, that would be great.

How to set up JNI sub directories in Android Studio

2 Answers2