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native function renderFrame to return jstring

By rorlich on Wed, 06/20/2012 - 17:10
Hello, i'm trying to modify the renderFrame function to return me the trackable name as jstring the changes: JNIEXPORT jstring JNICALL Java_com_qualcomm_QCARSamples_ImageTargets_ImageTargetsRenderer_renderFrame(JNIEnv* env, jobject obj) { jstring nameJ; nameJ = env->NewStringUTF("empty"); for(int tIdx = 0; tIdx < state.getNumActiveTrackables(); tIdx++) { .... nameJ = env->NewStringUTF(trackable->getName()); .... } ... ... Log("Done"); return nameJ; } I get an fatal from the logcat: 03-19 13:46:42.179: I/IMAGE_TARGETS(19903): Java_com_qualcomm_QCARSamples_ImageTargets_ImageTargetsRenderer_initRendering 03-19 13:46:42.218: D/QCAR(19903): GLRenderer::onSurfaceChanged 03-19 13:46:42.218: I/IMAGE_TARGETS(19903): Java_com_qualcomm_QCARSamples_ImageTargets_ImageTargetsRenderer_updateRendering 03-19 13:46:42.218: I/IMAGE_TARGETS(19903): Configure Video Background : Video (640,480), Screen (1196,720), mSize (1196,897) 03-19 13:46:42.226: I/IMAGE_TARGETS(19903): Done 03-19 13:46:42.226: A/libc(19903): Fatal signal 11 (SIGSEGV) at 0x0000001f (code=1) Any ideas how this can be done will be very helpful , Thanks from advance.

That's strange, I just tested this on a few different devices and it seems to work fine. Have you changed anything else? Did you update the method signature in the ImageTargetsRenderer class to reflect the new return type? [CODE] /** The native render function.