NDK in Android Studio not working

Question

I am doing every single step from video: https://www.youtube.com/watch?v=kFtxo7rr2HQ but no shared libraries are generated.

Here is a version, where android-studio should generate shared libraries on his own. However when I create apropraite Makefiles and execute ndk-build, shared libraries are not generated as well.

MainActivity.java:

public native String HelloJNI();

static
{
    System.loadLibrary("HelloJNI");
}

Build->Make Project

[*@* main]$ javah -d jni -classpath {sdk_dir}/platforms/android-14/android.jar:../../build/intermediates/classes/debug com.example.ndker.ndkapp.MainActivity

Creating HelloJNI.c:

#include "com_example_ndker_ndkapp_MainActivity.h"
JNIEXPORT jstring JNICALL Java_com_example_ndker_ndkapp_MainActivity_HelloJNI
        (JNIEnv *, jobject) {
    return (*env)->NewStringUTF(env, "Hello from jni");
}

local.properties:

sdk.dir={sdk_dir}
ndk.dir={ndk_dir}

build.grandle:

apply plugin: 'com.android.application'

android {
compileSdkVersion 21
buildToolsVersion "21.1.2"

defaultConfig {
    applicationId "com.example.ndker.ndkapp"
    minSdkVersion 14
    targetSdkVersion 21
    versionCode 1
    versionName "1.0"

    ndk {
        moduleName "HelloJNI"
    }
}

buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
}
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:21.0.3'
}

Thank You for replies.

score 2 · Accepted Answer · answered Jan 02 '15 at 04:11

I've created a blog post that documents setting up Android Studio, Gradle, and the NDK here: http://www.sureshjoshi.com/mobile/android-ndk-in-android-studio-with-swig/

Also, I've created a sample project in BitBucket with everything already set up for you here: https://bitbucket.org/sureshjoshi/android

Perhaps you could give those a try and see if they work for you?

The key thing is that Gradle will now automatically generate Makefiles and compile for you!

facundofarias · Answer 2 · 2014-12-21T16:35:21.093

0

Right. If you put the video on HD, you can then realize that to generate the native compilation, you should use ";" instead of ":". Like:

[*@* main]$ javah -d jni -classpath {sdk_dir}/platforms/android-14/android.jar;../../build/intermediates/classes/debug com.example.ndker.ndkapp.MainActivity

Here is an screenshot of the screen (taken from the video you've posted)

enter image description here

Let me know if that did the trick!

edited Dec 21 '14 at 16:35

answered Dec 21 '14 at 16:27

facundofarias

2,973
28
27

When I do it in that way, I receive: Error: no classes specified bash: ../../build/intermediates/classes/debug: Is a directory – galvanize Dec 21 '14 at 16:41
The same as here: http://stackoverflow.com/questions/27252712/android-studio-ndk-i-got-an-error-when-javah-d-jni-classpath – galvanize Dec 21 '14 at 16:47

NDK in Android Studio not working

2 Answers2