Object具有与成员函数不兼容的类型限定符

My class Game has a member EntityManager entityManager_.

我的类Game有一个成员EntityManager entityManager_。

The class EntityManager has a private member Player player_ and the public getter function Player &EntityManager::getPlayer() which returns player_.

EntityManager类有一个私有成员Player player_和公共getter函数Player&EntityManager :: getPlayer(),它返回player_。

The class Player has for example the functions void startMoving() and sf::Vector2f getPosition() const.

类Player具有例如void startMoving()和sf :: Vector2f getPosition()const的函数。

Now, I can without problems call entityManager_.getPlayer().startMoving(); from within my Game class, but when I try for example the following code to get the player's position:

现在,我可以毫无问题地调用entityManager_.getPlayer()。startMoving();从我的Game类中,但是当我尝试以下代码来获取玩家的位置时:

sf::Vector2f playerPosition = entityManager_.getPlayer().getPosition();

sf :: Vector2f playerPosition = entityManager_.getPlayer()。getPosition();

I get the following error:

我收到以下错误:

IntelliSense:

EntityManager Game::entityManager_

Error: the object has type qualifiers that are not compatible with the member function

object type is: const EntityManager

Output:

game.cpp(261): error C2662: 'EntityManager::getPlayer' : cannot convert 'this' pointer from 'const EntityManager' to 'EntityManager &'
          Conversion loses qualifiers

I tried removing the const from the player's getPosition function but nothing changed.

我尝试从播放器的getPosition函数中删除const,但没有任何改变。

I know it probably has something to do with the const but I can't figure out what to change! Could someone please help me?

我知道它可能与const有关但我无法弄清楚要改变什么!有人可以帮帮我吗?

1 个解决方案

#1

The error message is quite explicit:

错误消息非常明确:

game.cpp(261): error C2662: 'EntityManager::getPlayer' : 
               cannot convert 'this' pointer from 'const EntityManager' to 
                                                  'EntityManager &'
          Conversion loses qualifiers

In the context where you are calling getPlayer the object/reference is const. You cannot call a non-const member function on a const object or through a const reference or pointer to const.

在您调用getPlayer的上下文中,对象/引用是const。您不能在const对象上调用非const成员函数,也不能通过const引用或指向const的指针调用非const成员函数。

Because the error refers to this, the most likely reason is that this code is inside a member function that is const.

因为错误引用了这个,最可能的原因是这个代码在const的成员函数中。

#1