Folks,
I am working on an android application where I need a third party .so library. I built this third party library (with ndk-build) as per their instructions and was then looking to include this .so in to my Android project.
Therefore I followed the steps described in docs/PREBUILTS.html and successfully build the new .so in the jni/prebuilt directory. Now I tried leveraging the .so facilities by using it in a simple test android app. So what i do is :
static {
Log.i("load so > ","load so");
System.loadLibrary("xyz");
}
/* The native functions */
private static native int openFile(String filename);
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
try{
String path = getPathForDownloadDirectoryFile();
Log.i("file path> ", path);
int num= openFile(path);
}catch(Exception e){
Log.e(">", "could not open the file");
}
}
Now when I run my app I get a debug message saying : No JNI_OnLoad found in /data/data/com.example.myfirstapp/lib/xyz.so 0x411e6738, skipping init and then the application shuts down.
For More Info, Here is the error log :
No JNI_OnLoad found in /data/data/com.example.mysecondapp/lib/xyz.so 0x411e67a0, skipping init
W/dalvikvm( 570): No implementation found for native Lcom/example/mysecondapp/MainActivity;.openFile:(Ljava/lang/String;)I
D/AndroidRuntime( 570): Shutting down VM
W/dalvikvm( 570): threadid=1: thread exiting with uncaught exception (group=0x40a13300)
E/AndroidRuntime( 570): FATAL EXCEPTION: main
E/AndroidRuntime( 570): java.lang.UnsatisfiedLinkError: Native method not found: com.example.mysecondapp.MainActivity.openFile:(Ljava/lang/String;)I
E/AndroidRuntime( 570): at com.example.mysecondapp.MainActivity.openFile(Native Method)
E/AndroidRuntime( 570): at com.example.mysecondapp.MainActivity.onCreate(MainActivity.java:31)
E/AndroidRuntime( 570): at android.app.Activity.performCreate(Activity.java:5008)
E/AndroidRuntime( 570): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
E/AndroidRuntime( 570): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
E/AndroidRuntime( 570): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
E/AndroidRuntime( 570): at android.app.ActivityThread.access$600(ActivityThread.java:130)
E/AndroidRuntime( 570): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
E/AndroidRuntime( 570): at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime( 570): at android.os.Looper.loop(Looper.java:137)
E/AndroidRuntime( 570): at android.app.ActivityThread.main(ActivityThread.java:4745)
E/AndroidRuntime( 570): at java.lang.reflect.Method.invokeNative(Native Method)
E/AndroidRuntime( 570): at java.lang.reflect.Method.invoke(Method.java:511)
E/AndroidRuntime( 570): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
E/AndroidRuntime( 570): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
E/AndroidRuntime( 570): at dalvik.system.NativeStart.main(Native Method)
W/ActivityManager( 146): Force finishing activity com.example.mysecondapp/.MainActivity
As I could see that native implementation for the openFile() method was not found but the same xyz.so lib worked pretty neat with the original sample app from the third party. I am pretty much a starter with Android-ndk world.
Java-Android-NDK Ninjas ..any guess on what I might be missing ? I'll highly appreciate any help here :)
