Android NDK with build.gradle example

Android.mk

LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

LOCAL_MODULE := su

LOCAL_FORCE_STATIC_EXECUTABLE := true

LOCAL_STATIC_LIBRARIES := sqlite3 libcutils libc

LOCAL_C_INCLUDES := $(LOCAL_PATH)/sqlite3

LOCAL_SRC_FILES := super/su.c super/activity.c super/db.c super/utils.c super/daemon.c super/pts.c

include $(BUILD_EXECUTABLE)

include $(CLEAR_VARS)

LOCAL_MODULE := reboot

LOCAL_LDFLAGS := -llog

LOCAL_STATIC_LIBRARIES := sqlite3

LOCAL_C_INCLUDES := $(LOCAL_PATH)/sqlite3

LOCAL_SRC_FILES := reboot/reboot.c

include $(BUILD_EXECUTABLE)

include $(CLEAR_VARS)

LOCAL_MODULE := sqlite3

LOCAL_SRC_FILES := sqlite3/sqlite3.c

LOCAL_CFLAGS := -DSQLITE_OMIT_LOAD_EXTENSION

include $(BUILD_STATIC_LIBRARY)

build.gradle

--------------

import org.apache.tools.ant.taskdefs.condition.Os

import com.android.build.gradle.internal.api.ApplicationVariantImpl 

 apply plugin: 'com.android.application'

    android {

        compileSdkVersion 23

        buildToolsVersion  "23.0.1"

        defaultConfig.with {

            applicationId "com.iamsafe"

            minSdkVersion 15

            targetSdkVersion 23

        }

     buildTypes {

            debug {

                minifyEnabled = false

                useProguard = true

                proguardFiles.add(file('proguard-rules.txt'))

            }

        }

    }

dependencies {

    compile 'com.android.support:support-v4:23.0.1'

    compile files('libs/asmack-android-8-0.8.10.jar')

    compile files('libs/commons-io-2.0.1.jar')

    compile files('libs/httpclient-osgi-4.2.1-sources.jar')

    compile files('libs/httpcore-4.3.2.jar')

    compile files('libs/httpmime-4.1.2.jar')

}

buildscript {

    repositories {

        jcenter()

    }

    dependencies {

        classpath 'com.android.tools.build:gradle:2.1.2'

        classpath 'com.android.tools.build:gradle-experimental:0.7.2'

        // NOTE: Do not place your application dependencies here; they belong

        // in the individual module build.gradle files

    }

}

allprojects {

    repositories {

        jcenter()

    }

}

   project.ext.versionCodes = ['armeabi':1, 'armeabi-v7a':2, 'arm64-v8a':3, 'mips':5, 'mips64':6, 'x86':8, 'x86_64':9] //versionCode digit for each supported ABI, with 64bit>32bit and x86>armeabi-*

    

    // call regular ndk-build(.cmd) script from app directory

    task ndkBuild(type: Exec) {

        if (Os.isFamily(Os.FAMILY_WINDOWS)) {

 

            commandLine 'ndk-build.cmd', '-C', file('./').absolutePath

        } else {

            commandLine 'ndk-build', '-C', file('$buildFile.parent.name').absolutePath

        }

    }

    tasks.withType(JavaCompile) {

        compileTask -> compileTask.dependsOn ndkBuild

    }

Application.mk
--------------------
APP_ABI := x86 armeabi mips
APP_PIE = true


hello-jni.c
------------

//
// Created by vpilaka on 6/22/2016.
//

#include "hello-jni.h"

#include
#include

jstring
Java_com_example_android_camera2video_CameraActivity_getJniString(JNIEnv* env, jobject thiz){
    return (*env)->NewStringUTF(env, "Hello from JNI from Venkata Sitaram!");
}

Note: make sure that you activity.java class that should be in the same package as com.example.android.camera2video 

public class CameraActivity extends Activity{

public native String getJniString();

  

   public void onCreate(Bundle savendnInstance){

  //to do your code goes here 

}

}