Undefined reference to AAssetManager_fromJava

Issue

I am trying to access assets from an android apk using AAssetManager. However, I keep getting "Undefined reference to AAssetManager_fromJava" even though I've included asset_manager.h and asset_manager_jni.h Other functions from asset_manager.h, like AAssetManager_openDir(mgr, "") etc also can't be referenced.

Here's the complete code

#define EXPORT_API

#include <string.h>
#include <jni.h>
#include <android\log.h>

#include <sys\types.h>
#include <android\asset_manager.h>
#include <android\asset_manager_jni.h>

#define LOGD(...) __android_log_print(ANDROID_LOG_DEBUG, "com.devin - native", __VA_ARGS__)

JNIEnv* env=0;

#ifdef __cplusplus
extern "C" {
#endif

JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM* vm, void* pvt){
    LOGD("JNI_OnLoad() called");
    vm->AttachCurrentThread(&env, 0);
    return JNI_VERSION_1_2;
}

EXPORT_API void LoadAsset(char* filename, jobject assetManager){
    AAssetManager* mgr = AAssetManager_fromJava(env, assetManager);
        /* More stuff */
}

#ifdef __cplusplus
};
#endif

This code is in a .cpp file and being compiled with NDK R8. Am I doing something terribly wrong here?

Solution

My mistake. I didn't have "android" library added to the linker. I have actually setup NDK dev environment on Visual Studio Express and "android" library wasn't added to my project by default.

If you are using makefiles, be sure to add -landroid to your LOCAL_LDLIBS when using native AssetManager.

Answered By - devin