从jpanel中绘制和删除jlabels

Question

我正在制作一个国际象棋游戏gui，方法是设置一个顶部有jlabels的jpanels网格（棋子图像）。我设置了板，每个正方形（jpanel）都有一个空的jlabel w/visibility设置为false。然后，我浏览每个jpanel，并将jlabel图片设置为与我的一个作品相对应的图像。我知道是否画一幅，因为我有一个变量_board[8][8]，它告诉我这个位置是否被占用以及被谁占用。这就是我创建原始板的方式：

编辑：

事实上，我把它改了很多，这样我就不必每次都重新加载图像：

public ChessGameGUI(Square[][] board) throws IOException 
    {
        Dimension size = new Dimension(500, 400);
        Dimension boardSize = new Dimension(400, 400);
        layeredPane = new JLayeredPane();
        getContentPane().add(layeredPane);
        layeredPane.setPreferredSize(size);
        theBoard = new JPanel();
        layeredPane.add(theBoard, JLayeredPane.DEFAULT_LAYER);
        layeredPane.addMouseListener(this);
        GridLayout chessBoardLayout = new GridLayout(8,8);
        theBoard.setLayout(chessBoardLayout);
        theBoard.setPreferredSize(boardSize);
        theBoard.setBounds(0, 0, boardSize.width, boardSize.height);
        boolean drawWhite = true;
        // setup initial squares
        for(int y = 0; y < 8; y++)
        {
            for(int x = 0; x < 8; x++)
            {
                BorderLayout squareBorder = new BorderLayout();
                JPanel aChessSquare = new JPanel(squareBorder);
                if(drawWhite) aChessSquare.setBackground(Color.WHITE);
                else aChessSquare.setBackground(Color.GRAY);
                // load initial images
                if(board[x][y]._isOccupied)
                {
                    BufferedImage logo = null;
                    try{
                        // load the image
                        String path = findPieceImagePath(board, x, y);
                        logo = ImageIO.read(new File(path));
                        ImageIcon pieceImage = new ImageIcon(logo);
                        JLabel pieceJLabel = new JLabel();
                        pieceJLabel.setIcon(pieceImage); // new
                        pieceJLabel.setVisible(true); // new
                        aChessSquare.add(pieceJLabel);
                    } 
                    catch (IOException e)
                    { 
                        e.printStackTrace(); 
                    } // end try catch
                }// end if
                else
                {
                    JLabel pieceJLabel = new JLabel();
                    pieceJLabel.setVisible(false);
                    aChessSquare.add(pieceJLabel);
                }
                theBoard.add(aChessSquare);
                // alternate background colors
                if(x == 7);
                else drawWhite = !drawWhite;
            }
        }
        System.out.println("the number of components = " + theBoard.getComponentCount());
    }

这加载了最初的板很好，但我似乎无法获得特定的组件。当我点击其中一块时，那个方块应该会亮起来。唯一得到绿色轮廓的正方形是左上角的那个（0，0）。

public void mousePressed(MouseEvent e) 
    {
        System.out.println("mouse press x = " + e.getX() + " y = " + e.getY());
        // find which piece on the board is being clicked
        int gameX, gameY;
        gameX = e.getX() / 50;
        gameY = e.getY() / 50;
        System.out.println("gameX = " + gameX + " gameY = " + gameY);
        // out of bounds
        if(gameX < 0 || gameY < 0) return;
        // true if selected a piece on this team
        if(myGame._board[gameX][gameY]._isOccupied && !_pieceSelected && myGame._board[gameX][gameY]._team == myGame._turn) 
        {
            System.out.println("selected new piece");
            JPanel curSquare = (JPanel)theBoard.getComponentAt(gameX, gameY);
            curSquare.setBorder(BorderFactory.createLineBorder(Color.green));
            _pieceSelected = !_pieceSelected;

            return;
        }

我想我这行有问题：JPanel curSquare=（JPanel）theBoard。getComponentAt（gameX，gameY）；

然而，gameX和gameY值被正确设置。

感谢

Answer 1

我认为您缺少一行将标签添加到每个面板。在"//设置初始方块"期间：

curLabel.setVisible（false）；

应为：

curLabel.setVisible（false）；aChessSquare.add（curLabel）；