扩展的JPanel废墟GridLayout

Question

我想要像这样修改我的JPanel：

public class Square extends JPanel {
    private Checker fromChecker;
    private int x;
    private int y;

    Square(int x, int y){
        this.x = x;
        this.y = y;
    }

    public int getX(){ return this.x; }
    public int getY(){ return this.y; }

    void setPossibleMoveChecker(Checker fromChecker){ this.fromChecker = fromChecker; }
    Checker getPossibleMoveChecker(){ return this.fromChecker; }
}

我在这里打电话给Square ：

JPanel panel = new JPanel();
panel.setLayout(new GridLayout(Game.grid_size, Game.grid_size));

for(int x=1; x <= Game.grid_size; x ++){
    for(int y=1; y <= Game.grid_size; y ++) {
        Square square = new Square(x, y);

        // grid colour
        Color square_color = Game.grid1_colour;
        if((x + y) % 2 == 0){
            square_color = Game.grid2_colour;
        }
        square.setBackground(square_color);
        square.addMouseListener(new Mouse());
        panel.add(square);
    }
}

不幸的是，这就像：

好像我换线了：

Square square = new Square(x, y);

至

JPanel square = new JPanel();

它完美地像：

Answer 1

您正在覆盖两个关键的JComponent方法， getX()和getY() ，这会弄乱组件的位置，因为这是布局管理器用于组件放置的关键行为之一。

解决方案： 重命名这些方法！

public class Square extends JPanel {
    private Checker fromChecker;
    private int column;
    private int row;

    Square(int column, int row){
        this.column = column;
        this.row = row;
    }

    public int getColumn(){ 
        return this.column; 
    }

    public int getRow(){ 
        return this.row; 
    }

    // ....

支持组合优于继承的另一个原因，特别是在处理具有许多可能可重写方法的复杂类时。