从列表中删除和删除指针

Question

我有这段代码（它是复制错误的代码的 smol 版本），它给出了某种内存错误。 idk 请帮我解决它。它删除了对象，因此只剩下 nullptr。不知道为什么，但它不想从列表中删除指针。

#include <iostream>
#include <list>
// casual include

我在这里创建了一个 class 这是我所有其他 classes

的基础

class Object // a virtual class
{
public:
    bool needs_delete = false;

    virtual void tick() {}
    virtual void render() {}
};

一个播放器class继承自我之前创建的对象class

class Player : public Object
{
public:
    float x, y; // <-- just look at da code dont read dis

    Player(float x, float y) : // i initialize the "x" & "y" with the x & y the user has set in the constructor
        x(x), y(y)
    {}

    void tick() override // just look at the code
    {
        x++;
        if (x > 10000)
        {
            needs_delete = true;
        }
    }

    void render() override // just look at the code
    {
        // nothing...
    }
};

只是主要功能。在这一点上，我只是在写文字，因为 Whosebug 不会让我 post 这种持续的沮丧。请帮助:)

int main()
{
    std::list<Object*>* myObjs = new std::list<Object*>; // a list that will contain the objects

    for (int i = 0; i < 1000; i++) // i create 1k player just for testing
    {
        myObjs->push_back(new Player(i, 0));
    }

    while (true)
    {
        if (myObjs->size() == 0) // if there are no objects i just break out of the loop
            break;
        
        for (Object* obj : *myObjs) // update the objects
        {
            obj->tick();
            obj->render();

            // some other stuff
        }


        // DA PART I HAVE NO IDEA HOW TO DO
        // pls help cuz i suck

        for (Object* obj : *myObjs) // help pls :)
        {
            // baisicly here i want to delete the object and remove it from the list
            if (obj->needs_delete)
            {
                std::cout << "deleted object\n";
                delete obj;
                myObjs->remove(obj);
            }
        }

    }
}

Answer 1

怎么样：

myObjs->remove_if([](auto& pObj)
{
    if ( pObj->needs_delete )
    {
        delete pObj;
        return true;
    }
    else 
        return false;
});

从列表中删除和删除指针

Delete and remove a pointer from a list

c++

memory

pointers

list