Using objects in different classes

[bacondude95]

I have a question. I have been learning SFML and know C++ pretty well, But one thing I have never understood too well was using objects in different classes.
I've heard that you make a reference to the object and then use it in other classes but I don't understand how to do this with constructors because when I try the, constructor wont get called, But the program runs. What I'm mainly trying to do is use sf::RenderWindow in my other classes. I'm sorry if you get mad but this is something that never gets explained well.

[MikeyBoy]

You can use a class just like any other type. So if you know how to have a class own a data member of type int, you know how to make it own an object of a class type.

[3qX21hU5]

Are you trying to basically make a base Game class that handles the window and game flow?

If so here is a minor example of using sf::RenderWindow in a class which can give you a idea. Basically this is just taking the main game loop out of the main file and putting it inside of a class.

#include <SFML/Graphics.hpp>

class Game
{
    public:
        Game();
        void run();     // Runs the game

        void processEvents();   // This is where event handling goes
        void update(sf::Time deltaTime);        // Update logic here
        void render();      // Render stuff here.

    private:
        void handlePlayerInput(sf::Keyboard::Key key, bool isPressed);  // Helper for processing player input

    private:
        sf::RenderWindow window;
}

Game::Game() : window(sf::VideoMode(640, 480), "SFML Application")
{
}

void Game::run()
{
    // Main game loop here.
    // I left out managing deltatime and fps
    while (window.isOpen())
    {
        processEvents();
        update();       // You should pass deltatime to the update function
        render();
    }

}

void Game::processEvents()
{
    // Handle events here
    sf::Event event;
    while (window.pollEvent(event))
    {
        switch(event)
        {
            case sf::Event::Closed:
                window.close();
                break;

            case sf::Event::KeyPressed:
                handlePlayerInput(event.key.code, true);
                break;

            case sf::Event::KeyReleased:
                handlePlayerInput(event.key.code, false);
                break;
        }
    }
}

void Game::update(sf::Time deltaTime)
{
    // Update your game logic here.
    // Again remember to include deltatime
}

void Game::render()
{
    window.clear();
    window.displayer();
}

void Game::handlePlayerInput(sf::Keyboard::Key key, bool isPressed)
{
    // Handle key presses here. 
}

If you want more info we might need to know exactly what you are trying to do with your sf::RenderWindow objects in order to help.