Equal operator attempting to reference a deleted function, array

Question

I am using SFML to create a space invaders clone with C++. I am quite new to C++ and I'm learning it as I'm working on this project.

I am getting the following error when trying to create a new enemy using the constructor and array to set settings for each created enemy:

1>enemy.cpp
1>C:\Users\dzamm\source\repos\SFML\enemy.cpp(35,1): error C2280: 'Enemy &Enemy::operator =(const Enemy &)': attempting to reference a deleted function
1>C:\Users\dzamm\source\repos\SFML\enemy.h(55): message : compiler has generated 'Enemy::operator =' here
1>C:\Users\dzamm\source\repos\SFML\enemy.h(55,1): message : 'Enemy &Enemy::operator =(const Enemy &)': function was implicitly deleted because a data member invokes a deleted or inaccessible function 'sf::RenderWindow &sf::RenderWindow::operator =(const sf::RenderWindow &)'

Enemy Constructor:

Enemy alienArray[NUMBER_OF_ALIENS];

//constructor sets ID number, loads sprite
Enemy::Enemy(const int id, float sp)
{
    //set alive
    mIsAlive = true;

    //set speed
    enemySpeed = sp;

    // Load an enemy texture
    if (!mEnemyTexture.loadFromFile("Media/Textures/PixelSpaceships/red_01.png")) {
        // Handle loading error
        std::cout << "Oh No! File not loaded." << std::endl;
    }

    //scale sprite and set texture so we know size
    enemySprite.setTexture(mEnemyTexture);
}

Enemy loader method

void Enemy::loader(int noOfAliens) { // might add xPosition;yPosition

    for (int i = 0; i < noOfAliens; i++)
    {
        Enemy alien(i, 10.f); // speed issue
        alien.setLocation(i * 100.f + 50.f, alien.getSprite().getGlobalBounds().height / 2);
line 35     alienArray[i] = alien;
        //alienArray.push_back(alien);
    }
}

1>C:\Users\dzamm\source\repos\SFML\enemy.cpp(35,1): error C2280: 'Enemy &Enemy::operator =(const Enemy &)': attempting to reference a deleted function

Enemy Header file:

#include <SFML/System.hpp>
#include <SFML/Window.hpp>
#include <SFML/Graphics.hpp>
#include <SFML/Network.hpp>
#pragma once

#define NUMBER_OF_ALIENS 4

//class Game;
class Enemy
{
public:
    //constructor sets ID number, loads sprite
    Enemy() {};
    Enemy(const int, float);
    sf::Sprite&             getSprite();
    void                    kill();
    bool                    isAlive();
    void                    load();
    void                    loader(const int noOfAliens);
    void                    setLocation(float xPosition, float yPosition);
    void                    enemyInstantiator(int noOfEnemies, float xPosition, float yPosition);
    void                    update();
    void                    render(sf::RenderWindow& window);

private:

    void                    enemyBehaviour(std::vector<sf::Sprite>& enemyList);
    void                    enemyMovement(std::vector<Enemy>& enemyList);

private:


    sf::Texture             mEnemyTexture;
    sf::Sprite              enemySprite;


    //std::vector<Enemy>        alienArray;
    //std::vector<sf::Sprite> mEnemies;
    sf::RectangleShape      mEnemyBounds;

    sf::RenderWindow        mWindow;


    bool                    mIsShooting;
    bool                    mIsAlive;
    float                   enemySpeed;
};

I read on forums that issue is related to working with a copy of the object instead of the original object, however I am not sure how to handle this to reference the original object I'm modifying.

To reproduce create a constructor for Enemy.cpp class, create an entity Enemy alien using for loop in method as shown in Enemy::loader and store the created entity in the Enemy alienArray as shown by index.

Answer 1

The issue was related to an sf::RenderWindow reference that was not being even utilised in the code.

sf::RenderWindow &sf::RenderWindow::operator =(const sf::RenderWindow &)

Once I removed this all errors disappeared.