假设有两个类,一个是abstract class Insect,另一个是class Beetle extends Insect。因此,在main中实例化Beetle对象时,可以使用Insect beetle = new Beetle();或Beetlebeetle = new Beetle();。但是如果使用Insect beetle = new Beetle();实例化,则需要强制转换才能使用子Beetle类中的
lateinit var listView: ListViewlateinit var beetleList:MutableList<Beetleval beetleName=intent.getStringExtra("Beetle")
ref = FirebaseDatabase.getInstance().getReference("
1>Bettle_Dice.obj : error LNK2019: unresolved external symbol "public: int __thiscall Beetle::checkcomcheckcom@Beetle@@QAEHXZ) referenced in function _main下面是我的代码main.cpp#include "beetle.h