Android已有项目（Android studio下开发）嵌入一个用Cocos做的小游戏，应该怎么接入？
错误代码：
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method ‘void org.cocos2dx.lib.Cocos2dxActivity.runOnGLThread(java.lang.Runnable)’ on a null object reference
at org.cocos2dx.lib.Cocos2dxHelper.runOnGLThread(Cocos2dxHelper.java:109)
at org.cocos2dx.lib.Cocos2dxAudioFocusManager.unregisterAudioFocusListener(Cocos2dxAudioFocusManager.java:121)
at org.cocos2dx.lib.Cocos2dxActivity.onDestroy(Cocos2dxActivity.java:207)
at android.app.Activity.performDestroy(Activity.java:6528)
at android.app.Instrumentation.callActivityOnDestroy(Instrumentation.java:1143)
at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3903)
at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3934)
at android.app.ActivityThread.access$1600(ActivityThread.java:156)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1463)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5637)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:746)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:636)
at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:102)