PowenKo, NDK Tutorial 05, my first NDK on Eclipse

#. create a Android project “MyAndroidProject”

#. In file manager create  “jni” directory in your project directory

#. create a jni/Android.mk

Simple example of Android.mk file:
LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

LOCAL_LDLIBS    := -llog

LOCAL_MODULE    := native
LOCAL_SRC_FILES := native.c

include $(BUILD_SHARED_LIBRARY)



and place your C/C++ sources file here. Also put here Android.mk file which is a makefile that tells Android build-system how to build your files.
#.  create a jni/native.c
 
#include
#include

/* This is a trivial JNI example where we use a native method
 * to return a new VM String. See the corresponding Java source
 * file located at:
 *
 *   apps/samples/hello-jni/project/src/com/example/HelloJni/HelloJni.java
 */
//jstring Java_com_example_hellojni_HelloJni_stringFromJNI( JNIEnv* env, jobject thiz )
jstring Java_com_powenko_Tutorial_NDK_MyAndroidProject_Tutorial_NDK_MyAndroidProjectActivity_stringFromJNI( JNIEnv* env, jobject thiz )
{
    return (*env)->NewStringUTF(env, "Hello PowenKo from JNI ! My first NDK");
}


#.Now create a folder called jni, and change perspective to C/C++. Right click the project in the Project Explorer tab and choose New->Convert to a C/C++ project. ChooseC++ Project, check Specify Project Type, set it to Makefile project and –Other Toolchain–. Click Finish.

 
After doing this Eclipse will ask you if you want to switch to C/C++ perspective. ChooseYes because otherwise you wouldn’t be able to set C/C++ build preferences.
 
 
#. Click on your project with right button and select Properties or press Alt+Enter
Properties windows will appear. Here you have to configure use of ndk-build instead of make all command and set proper include paths.
 
#. Choose C/C++ Build and configure ndk-build as a build command
In Builder settings fill ndk-build into Build command entry. You have to uncheck Use default build command. You also need to have ndk-build script in your PATH.

 

 
Click Apply to save settings.
8) Choose C/C++ General->Paths and Symbols and configure include path
In Includes tab choose GNU C or GNU C++ and click Add… button. Add path to include directory which is located in platforms/android-4/arch/arm/usr/include subdirectory of place where you’ve unpacked Android ndk. Include path depends on target for which you are compiling (android-4 in my case — i.e. Android 1.6).
 
 
 

sample code:

Tutorial_NDK_MyAndroidProject