He estado siguiendo esta guía sobre cómo portar la biblioteca LAME con Android NDK. http://blog.libertadtech.com/2011/02/porting-lame-encoder-to-android-arm.htmlInvocando funciones nativas de la biblioteca portada
Cada funcionó bien un i tenga el archivo libmp3lame.so.
Ahora, para una primera prueba que quería llamar a la función simple:
void get_lame_version(char *strbuf, size_t buflen, const char *prefix);
He escrito un contenedor para la biblioteca LAME:
package de.goddchen.android.youtubeconverter;
public class LameWrapper {
public static native void get_1lame_1version(char[] buf, int len,
char[] prefix);
}
Y llamo de esta manera:
public class MainActivity extends Activity {
static {
System.loadLibrary("mp3lame");
}
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
char[] buffer = new char[100];
LameWrapper.get_1lame_1version(buffer, 100, "".toCharArray());
((TextView) findViewById(R.id.text)).setText(buffer.toString());
}
}
Pero me sale el siguiente error:
05-05 10:36:11.973: DEBUG/dalvikvm(199): Trying to load lib /data/data/de.goddchen.android.youtubeconverter/lib/libmp3lame.so 0x43757f78
05-05 10:36:12.053: DEBUG/dalvikvm(199): Added shared lib /data/data/de.goddchen.android.youtubeconverter/lib/libmp3lame.so 0x43757f78
05-05 10:36:12.123: DEBUG/dalvikvm(199): No JNI_OnLoad found in /data/data/de.goddchen.android.youtubeconverter/lib/libmp3lame.so 0x43757f78
05-05 10:36:12.573: DEBUG/dalvikvm(199): +++ not scanning '/system/lib/libwebcore.so' for 'get_1lame_1version' (wrong CL)
05-05 10:36:12.693: DEBUG/dalvikvm(199): +++ not scanning '/system/lib/libexif.so' for 'get_1lame_1version' (wrong CL)
05-05 10:36:12.693: DEBUG/dalvikvm(199): +++ not scanning '/system/lib/libFFTEm.so' for 'get_1lame_1version' (wrong CL)
05-05 10:36:12.703: DEBUG/dalvikvm(199): +++ not scanning '/system/lib/libmedia_jni.so' for 'get_1lame_1version' (wrong CL)
05-05 10:36:12.703: DEBUG/dalvikvm(199): +++ not scanning '/system/lib/libsrec_jni.so' for 'get_1lame_1version' (wrong CL)
05-05 10:36:12.703: WARN/dalvikvm(199): No implementation found for native Lde/goddchen/android/youtubeconverter/LameWrapper;.get_1lame_1version ([CI[C)V
05-05 10:36:12.703: DEBUG/AndroidRuntime(199): Shutting down VM
05-05 10:36:12.753: INFO/ActivityManager(52): Start proc com.android.alarmclock for broadcast com.android.alarmclock/.AlarmInitReceiver: pid=213 uid=10017 gids={}
05-05 10:36:12.773: WARN/dalvikvm(199): threadid=3: thread exiting with uncaught exception (group=0x4001aa28)
05-05 10:36:12.783: ERROR/AndroidRuntime(199): Uncaught handler: thread main exiting due to uncaught exception
05-05 10:36:12.883: ERROR/AndroidRuntime(199): java.lang.UnsatisfiedLinkError: get_1lame_1version
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at de.goddchen.android.youtubeconverter.LameWrapper.get_1lame_1version(Native Method)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at de.goddchen.android.youtubeconverter.MainActivity.onCreate(MainActivity.java:19)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2364)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at android.app.ActivityThread.access$2100(ActivityThread.java:116)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at android.os.Handler.dispatchMessage(Handler.java:99)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at android.os.Looper.loop(Looper.java:123)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at android.app.ActivityThread.main(ActivityThread.java:4203)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at java.lang.reflect.Method.invokeNative(Native Method)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at java.lang.reflect.Method.invoke(Method.java:521)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
05-05 10:36:12.883: ERROR/AndroidRuntime(199): at dalvik.system.NativeStart.main(Native Method)
¿Puede alguien indicarme la forma correcta de llamar a las funciones de libmp3lame.so?
¿Quizás necesites agregar palabra final? vacío nativo estático público get_1lame_1version (char [] buf, int len, final char [] prefix); – Pasha
pues no, no funciona :( – Goddchen
vistazo a esto: http://groups.google.com/group/android-ndk/browse_thread/thread/186678942625f46a/557bfe20de389d24 – Pasha