Android项目中的C++ Firebase链接错误

我正在尝试将firebase c ++ sdk添加到我的cocos2d-x 3.14游戏中.到目前为止,我在firebase_cpp_sdk目录中创建了Android.mk:

LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)
LOCAL_MODULE := firebase-prebuilt
LOCAL_SRC_FILES := libs/android/$(TARGET_ARCH_ABI)/c++/libapp.a
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
include $(PREBUILT_STATIC_LIBRARY)


include $(CLEAR_VARS)
LOCAL_MODULE := firebase-analytics
LOCAL_SRC_FILES := libs/android/$(TARGET_ARCH_ABI)/c++/libanalytics.a
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
include $(PREBUILT_STATIC_LIBRARY)

然后在Android.mk的项目中我添加了:

LOCAL_C_INCLUDES += /Users/piotr/Documents/pierdoly/firebase_cpp_sdk/include

LOCAL_STATIC_LIBRARIES += firebase-prebuilt firebase-analytics

$(call import-add-path, /Users/piotr/Documents/pierdoly/firebase_cpp_sdk)

我可以同步gradle和构建项目.我也可以

#include  

在AppDelegate.cpp(或h)中,它工作正常.即使Android工作室也能看到所有的firebase标题,我可以检查它们.

现在,在applicationDidFinishLaunching中我添加了这个:

#if (CC_TARGET_PLATFORM != CC_PLATFORM_ANDROID)
    ::firebase::App* app = ::firebase::App::Create(::firebase::AppOptions());
#else
    ::firebase::App* firebaseApp = ::firebase::App::Create(::firebase::AppOptions(), cocos2d::JniHelper::getEnv(), cocos2d::JniHelper::getActivity());
#endif

还有来自AppActivity.java的JNICALL的替代版本(传递正确的活动,因为有人说上面的解决方案不起作用):

#if (CC_TARGET_PLATFORM == CC_PLATFORM_ANDROID)
JNIEXPORT void JNICALL Java_org_cocos2dx_cpp_AppActivity_initFirebase(JNIEnv* env, jobject thiz)
{
    ::firebase::App* app = ::firebase::App::Create(::firebase::AppOptions(), env, thiz);
}
#endif

但我的问题是:它甚至不会编译.有链接器错误:

Error:(141) undefined reference to 'firebase::App::Create(firebase::AppOptions const&, _JNIEnv*, _jobject*)'

我可以在Android Studio中清楚地"进入"此功能,并且我已经重新检查了两次我给的参数.他们很好.链接器对我大吼大叫.

我该如何修复链接器？我在这里错过了什么？