Note that there is an android-ndk Google Group for NDK-related questions. On Wed, Oct 19, 2011 at 4:51 PM, BBB <[email protected]> wrote: > Hi Everyone, > > I have an issue where (*env)->CallStaticVoidMethod is crashing. I am > caching the jvm, class and method id on JNI_OnLoad. In JNI_OnLoad i > start a thread! in that thread I want to call back a java method which > I am having problems with. Also should I be using JNI_VERSION_1_2 or > JNI_VERSION_1_4? > > JavaVM *cached_jvm; > jclass Class_C; > jmethodID MID_C_callback; > > > JNIEXPORT jint JNICALL > JNI_OnLoad(JavaVM *jvm, void *reserved) > { > __android_log_print(ANDROID_LOG_DEBUG, "JNI_OnLoad", > "JNI_OnLoad - start"); > > JNIEnv *env; > jclass cls; > // cache the jvm > cached_jvm = jvm; > > if ((*jvm)->GetEnv(jvm, (void **)&env, JNI_VERSION_1_2)) { > __android_log_print(ANDROID_LOG_DEBUG, "JNI_OnLoad", > "ERROR: GetEnv failed "); > > return JNI_ERR; // JNI version not supported; > } > > cls = (*env)->FindClass(env, > "com/bla/bla/xxxActivity"); > > if (cls == NULL) { > __android_log_print(ANDROID_LOG_DEBUG, "JNI_OnLoad", > "ERROR: FindClass failed"); > > return JNI_ERR; > } > > /* Use weak global ref to allow C class to be unloaded */ > Class_C = (*env)->NewWeakGlobalRef(env, cls); > if (Class_C == NULL) { > __android_log_print(ANDROID_LOG_DEBUG, "JNI_OnLoad", > "ERROR; NewWeakGlobalRef failed "); > > return JNI_ERR; > } > > /* Compute and cache the method ID */ > MID_C_callback = (*env)->GetStaticMethodID(env, cls, "callback", > "()V"); > if (MID_C_callback == NULL) { > __android_log_print(ANDROID_LOG_DEBUG, "JNI_OnLoad", > "ERROR:GetStaticMethod failed > "); > return JNI_ERR; > } > > startMyThread(); > > return JNI_VERSION_1_2; > } > > void startMyThread() > { > pthread_t myThread; > int rc; > rc = pthread_create(&myThread, NULL, (void *) &workerFunction, NULL); > if (rc) { > __android_log_print(ANDROID_LOG_DEBUG, GENERAL_LOG, > "ERROR starting pulse detection thread "); > } > } > > static void workerFunction() > { > JNIEnv *env; > int status = (*cached_jvm)->AttachCurrentThread(cached_jvm, &env, > NULL); > // status is 0 which means success > (*env)->CallStaticVoidMethod(env, Class_C, MID_C_callback); // > this crashes > > } > > -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/android-developers?hl=en >
-- Mark Murphy (a Commons Guy) http://commonsware.com | http://github.com/commonsguy http://commonsware.com/blog | http://twitter.com/commonsguy _Android Programming Tutorials_ Version 4.0 Available! -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
