I am working on a small 2d game engine for android-ndk using opengl.
I am facing difficulty on how to change levels, eg. from menu to game screen.
Because the texture ids are not working when loading new textures for game screen using glGenTextures, glGenTextures keeps returning duplicate ids.

```
// class to bind ndk with java
Renderer.java
void onSurfaceChanged(gl, width, height){
     nativeSurfaceChanged();
}

void onDrawFrame(){
     nativeDrawFrame();
}

// c++ code
Game.cpp
Screen *screen;
void SetScreen(Screen *scrn){
    screen = scrn;

    // load textures and create openGL objects (mesh and textures)
    screen->Initialize();
}
void Update(){
     screen->Update();
     screen->Render();
}

NDKActivity.cpp
Game *game;
void nativeSurfaceChanged(){
    // initlizes stuff like audio engine, rendering engine
    game->Initialize();

    // set current screen to main menu
    game->SetScreen(new MainMenu());
}
void nativeDrawFrame(){
    game->Update();
}

MainMenu.cpp
void Update(){
    // if some button is clicked
    game->SetScreen(new GameScreen());
}

```

Now when menu is initialized, everything works fine. But on loading GameScreen textue ids get all mixed up

I basically ported it from windows app where I was using GLUT for creating OpenGL context and there it was working fine. 

And please let me know if more info is needed