Important: Please read the Qt Code of Conduct -

Callback C++ function from Java: object references mismatch

  • I have QAndroidJniObject (CppClass::jniObject) with class instance. MyJavaClass calls native callback anSignalFromJava()

    static native void anSignalFromJava();

    Callback function on C++ side:

    extern "C" {
    JNIEXPORT void JNICALL Java_org_example_MyJavaClass_anSignalFromJava(JNIEnv* env, jobject object) {
      qDebug() << "callback object=" << object << "CppClass::jniObject.object()=" << CppClass::jniObject.object(); 
    //output: callback object=0xbea037fc CppClass::jniObject.object()=0x572
      Q_ASSERT(object == CppClass::jniObject.object()); //fail

    References to same Java object provided by QAndroidJniObject and object parameter of callback function differs, but they should be same

Log in to reply