void cocos_android_app_init (struct android_app* app) {
LOGD("cocos_android_app_init");
AppDelegate *pAppDelegate = new AppDelegate();
}

static void cocos_init(cocos_dimensions d, struct android_app* app) {
    LOGI("cocos_init(...)");
    pthread_t thisthread = pthread_self();
    LOGI("pthread_self() = %X", thisthread);

    cocos2d::FileUtilsAndroid::setassetmanager(app->activity->assetManager);

    if (!cocos2d::Director::getInstance()->getOpenGLView())
    {
        cocos2d::EGLView *view = cocos2d::EGLView::getInstance();
        view->setFrameSize(d.w, d.h);

        cocos_android_app_init(app);

        cocos2d::Application::getInstance()->run();
    }
    else
    {
        cocos2d::GL::invalidateStateCache();
        cocos2d::ShaderCache::getInstance()->reloadDefaultShaders();
        cocos2d::DrawPrimitives::init();
        cocos2d::VolatileTextureMgr::reloadAllTextures();
        cocos2d::EventCustom foregroundEvent(EVENT_COME_TO_FOREGROUND);
        cocos2d::Director::getInstance()->getEventDispatcher()->dispatchEvent(&foregroundEvent);
        cocos2d::Director::getInstance()->setGLDefaultValues(); 
    }
}

cocos2d::Application::getInstance()->run();
就调用了开发者的代码，游戏就运行起来了，在engine_draw_frame中，调用了cocos2d::Director::getInstance()->mainLoop();

static void engine_draw_frame(struct engine* engine) {
    LOG_RENDER_DEBUG("engine_draw_frame(...)");
    pthread_t thisthread = pthread_self();
    LOG_RENDER_DEBUG("pthread_self() = %X", thisthread);

    if (engine->display == NULL) {
        // No display.
        LOGW("engine_draw_frame : No display.");
        return;
    }

    dispatch_pending_runnables();
    cocos2d::Director::getInstance()->mainLoop();
    LOG_RENDER_DEBUG("engine_draw_frame : just called cocos‘ mainLoop()");

    /* // Just fill the screen with a color. */
    /* glClearColor(((float)engine->state.x)/engine->width, engine->state.angle, */
    /*         ((float)engine->state.y)/engine->height, 1); */
    /* glClear(GL_COLOR_BUFFER_BIT); */    
    
    if (s_pfEditTextCallback && editboxText)
    {
        s_pfEditTextCallback(editboxText, s_ctx);
        free(editboxText);
        editboxText = NULL;
    }    

    eglSwapBuffers(engine->display, engine->surface);
}