// Geeft true als kleur schaak staat
//Kleur (color) is the parameter to decide for what color to check
//if the king of that color is checked
bool game::schaak(zw kleur) {
    //Getting the opposite color
    //If kleur = white (wit), oppositeColor
    //is black (zwart)
    zw oppositeColor = zwart;

    //Setting the king (white or black)
    //in variable schaakStuk* king;
    schaakStuk* king = witKoning;
    string color = "Wit staat schaak!!"; //String to display in message
    if (kleur == zwart) {
        //If the color-parameter is black, oppositeColor
        //and king should be changed related to color
        oppositeColor = wit;
        king = zwartKoning;
        color = "Zwart staat schaak!!!";
    }

    //Vector holding valid moves (read more below)
    vector<string> v;
    //Iterating over all chess pieces on the board
    for (auto i : schaakStukken) {
        //If chess-piece is of opposite color
        if (i.second->getKleur() == oppositeColor) {
            //Setting all valid moves of chess-piece
            //in current iteration
            v = i.second->geldige_zetten(*this, i.first);

            //Iterating over all valid positions of chess-piece
            //in current iteration
            for (auto j : v) {
                //if one of the valid possible positions equals to
                //the enemy's king position
                if (j == king->getCurrentPositie().str()) {
                    //Show message and return
                    QMessageBox joehoe;
                    joehoe.setText(QString::fromStdString(color));
                    joehoe.exec();

                    //Outputting all valid positions
                    cout << "j " << j << endl;

                    //Temporarily commented out
                    //return true;
                }
            }
        }
    }

    return false;
}

MainWindow::setPiece()

void MainWindow::update()

MainWindow::clicked()