Android NDK RegisterNatives more full example

Issue

I'm try to make Android Native C++ project in Android Studio 2020.3.1. Here and here provided common tips for using RegisterNatives in JNI_OnLoad. But in this examples i can't understand what is nativeFoo and nativeBar ? These are methods or functions of c++ code? And what is doing MyClass in example ? I want more full and clear code example for Android NDK C++ native. Thank you!

Solution

Going backwards from the RegisterNatives call in the first link, it hooks up native C++ methods to the following Java class:

package com.example.app.package;

class MyClass {
    public native void nativeFoo();
    public native bool nativeBar(String, int);
}

and it expects that you defined the following C++ functions earlier:

JNIEXPORT void JNICALL nativeFoo(JNIEnv *env, jobject object) { ... }
JNIEXPORT jboolean JNICALL nativeBar(JNIEnv *env, jobject object, jstring a, jint b) { ... }

Answered By - Botje