2

我是 C++ 新手。我正在使用 SFML 和 Box2D 开发突破克隆，编译时出现此错误。错误详情：

c:\program files (x86)\visual studio express 2013\vc\include\xutility(2420): error C2280: 'Tile &Tile::operator =(const Tile &)' : attempting to reference a deleted function
c:\users\harry\documents\visual studio 2013\projects\cpp-breakout\cpp-breakout\entities\tile.hpp(27) : compiler has generated 'Tile::operator =' here

当我尝试使用 vector.erase 从 std::vector< Tile> 中擦除 Tile 对象时出现错误。

Tile.h

class Tile : public Entity {
public:
    Tile(b2World* world, float posX, float posY);
    void draw(sf::RenderWindow& window);

    const float PTM_RATIO = 32.f;
    const int HALF_WIDTH = 32;
    const int HALF_HEIGHT = 16;
    int armor;
    bool flaggedToErase = false;

    b2Body* tileBody;
    sf::Sprite sprite;
};

Tile.cpp

Tile::Tile(b2World* world, float posX, float posY)
{
    // Define a body.
    b2BodyDef tileBodyDef;
    tileBodyDef.type = b2_staticBody;
    tileBodyDef.position.Set((posX + HALF_WIDTH) / PTM_RATIO, (posY + HALF_HEIGHT) / PTM_RATIO);

    // Use the body definition to create the actual body instance.
    tileBody = world->CreateBody(&tileBodyDef);
    tileBody->SetUserData(this);
    // Define shape.
    b2PolygonShape tileShape;
    tileShape.SetAsBox(HALF_WIDTH / PTM_RATIO, HALF_HEIGHT / PTM_RATIO);

    // Define fixture.
    b2FixtureDef tileFixtureDef;
    tileFixtureDef.shape = &tileShape;
    tileFixtureDef.density = 10.0f;
    tileFixtureDef.restitution = 0.1f;
    tileFixtureDef.friction = 0.0f;
    //tileFixtureDef.isSensor = true;

    bUserData* bud = new bUserData;
    bud->entityType = TILE;
    tileFixtureDef.userData = bud;

    // Create fixture.
    tileBody->CreateFixture(&tileFixtureDef);
}

我将 Tiles 推到向量中

Level.cpp

std::vector<Tile> solidTiles;

void Level::loadLevel(b2World* world) {
    // Loop through the map and set the tile position and sprites to the tiles.
    for(unsigned int i = 0; i < map.size(); i++) {
        for(unsigned int j = 0; j < map[i].size(); j++) {
            // Set sprites to the tiles in every grid cell which is not -1,-1.
            if(map[i][j].x != -1 && map[i][j].y != -1) {
                Tile tempTile(world, j * TILE_WIDTH, i * TILE_HEIGHT);
                tempTile.sprite = tiles;
                tempTile.sprite.setOrigin(sf::Vector2f(HALF_WIDTH, HALF_HEIGHT));
                tempTile.sprite.setTextureRect(sf::IntRect(map[i][j].x * TILE_WIDTH, map[i][j].y * TILE_HEIGHT, TILE_WIDTH, TILE_HEIGHT));
                tempTile.sprite.setPosition(sf::Vector2f(tempTile.tileBody->GetPosition().x * PTM_RATIO, tempTile.tileBody->GetPosition().y * PTM_RATIO));
                solidTiles.push_back(tempTile);
            }
        }
    }
}

我试着擦掉里面的瓷砖

PlayState.cpp

void PlayState::removeSprites() {
    for(unsigned int i = 0; i < level1.solidTiles.size(); i++) {
        if(level1.solidTiles[i].flaggedToErase == true) {
            level1.solidTiles.erase(level1.solidTiles.begin() + i);
        }
    }
}

问题是否与移动构造函数/赋值有关？

4

2 回答 2

9

由于该类Tile具有const 数据成员，因此其由编译器复制赋值运算符隐式定义的定义为已删除。

您必须自己明确定义复制赋值运算符。

于 2014-07-23T21:23:33.823 回答
0

错误清楚地提到Tile &Tile::operator =(const Tile &)了，所以它是关于赋值运算符，而不是移动赋值运算符。您需要为Tile. 您还缺少Tile' 的复制构造函数。

从这里引用：

类 T 的隐式声明或默认复制赋值运算符在以下任何一项为真时定义为已删除：

  • T 有一个非静态数据成员，即 const
  • T 具有引用类型的非静态数据成员。
  • T 具有无法复制分配的非静态数据成员（已删除、不可访问或不明确的复制分配运算符）
  • T 具有无法复制分配的直接或虚拟基类（已删除、不可访问或模棱两可的移动赋值运算符）
  • T 有一个用户声明的移动构造函数
  • T 有一个用户声明的移动赋值运算符
于 2014-07-23T21:20:31.557 回答