你好我有三个班
PlayerSoccerTeam 是 AbstSoccerTeam 的子类。
bool AlanSoccerTeam::isClosestTeamMemberToSupportingPlayer(FieldPlayer* plyr)
是球员足球队的一种方法。
我试图用这个在 PlayersFieldPlayerStates 类中调用该方法
PlayersSoccerTeam* sTeam;
sTeam->isClosestTeamMemberToSupportingPlayer(player);
我运行它时会遇到这个问题
使用了未初始化的局部变量“sTeam”
我不知道发生了什么或为什么我收到此错误。
非常感谢您的帮助
The problem is you have created a pointer to a PlayersSoccerTeam but you have not actually created the object itself yet.
I would suggest doing this.
PlayersSoccerTeam sTeam;
sTeam.isClosestTeamMemberToSupportingPlayer(player);
You could alternatively do this.
PlayersSoccerTeam* sTeam = new PlayersSoccerTeam()
sTeam->isClosestTeamMemberToSupportingPlayer(player);
As perhaps an interesting education experience create a constructor that prints something to stdout when it is run and then try doing these two options and yours to see what happens. A constructor will be run whenever a new object is created.
PlayersSoccerTeam* sTeam;
这一行声明了一个指向 a 的指针，仅此PlayersSoccerTeam而已。你从这一行得到的只是一个指针。由于您尚未初始化，因此它没有特别指向任何地方。没有PlayersSoccerTeam任何地方可以指向。
如果你想要一个类型的对象PlayersSoccerTeam，那么你只想要：
PlayersSoccerTeam sTeam;
sTeam.isClosestTeamMemberToSupportingPlayer(player);
由于您告诉我们您的层次结构，因此您可能希望将您的PlayersSoccerTeam多态用作AbstSoccerTeam. 在这种情况下，您将需要使用指针或引用。这可以这样做：
AbstSoccerTeam* sTeam = new PlayersSoccerTeam();
// ...
delete sTeam;
请注意，这仍然只声明了一个指针，但该表达式new PlayersSoccerTeam还创建了一个PlayersSoccerTeam指针指向的对象。请注意，将指向 aPlayersSoccerTeam的指针分配给指向其父级的指针是完全可以的AbstSoccerTeam——这就是多态性。如果你这样做，你必须确保你delete sTeam;以后，否则对象将被泄露。
处理动态分配对象的用户的一种更安全的方法是使用智能指针，您可以这样做：
std::unique_ptr<AbstSoccerTeam> sTeam(new PlayersSoccerTeam());
现在您将不必这样做delete，因为它std::unique_ptr会为您处理。