Sprite *mole4 = Sprite::create("CloseNormal.png");
mole4->setPosition(hole4]);
this->addChild(mole4,2);
这是我创建精灵并加入layer的方法,编译器没有报错,但运行之后会卡住,报错为:Assertion failed: (child != nullptr), function addChild, file /Users/tmesoftware/Documents/workspace/NxGame/NxGame/cocos2d/cocos/2d/CCNode.cpp, line 779.
创建精灵:

报错的函数:

请问怎么解决?