我有一个名为BoardSquare的类，它是JButton的继承类。每个BoardSquare对象都存储在数组BoardSquare[][] boardsquares中。我使用了以下代码
BoardSquare.boardSquares[j][i].add(new JLabel((j+1)+":"+(i+1)));
根据坐标为数组中的每个方块添加标签。我需要他们拥有这些标签（我认为）以便我可以识别它们和addActionListeners等。如何让JLabel隐藏起来以便它们不会出现在我的JFrame中？
或者，如何让每个按钮的JLabel成为一个实例变量，以便我可以调用JLabel.setVisible(false)但在添加动作侦听器时仍然使用它们？
编辑：如果有人有兴趣，那就是跳棋游戏。
以下是我的课程：
GameWindow
BoardSquare
Checker
MyListener
答案 0 :(得分：3)
感谢您的编辑。如果这是我的申请，我可能会做的事情非常不同，包括
请注意，如果您必须使用JButtons，则不要向其添加JLabel。而只需将JButton的Icon设置为null或适当的Checker ImageIcon。
修改
例如，一个糟糕的代码示例作为概念证明。尝试编译并运行它。
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.GridLayout;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.util.EnumMap;
import java.util.Map;
import javax.swing.*;
@SuppressWarnings("serial")
public class Checkers extends JPanel {
public static final int SIDE_LENGTH = 60;
public static final int ROW_COUNT = 8;
private static final String ROW = "row";
private static final String COLUMN = "column";
private static final Color LIGHT_COLOR = new Color(210, 180, 140);
private static final Color DARK_COLOR = new Color(107, 68, 35);
private Map<Checker, Icon> checkerIconMap = new EnumMap<Checker, Icon>(
Checker.class);
private JLabel[][] labelGrid = new JLabel[ROW_COUNT][ROW_COUNT];
private Checker[][] checkerGrid = new Checker[ROW_COUNT][ROW_COUNT];
public Checkers() {
for (Checker checker : Checker.values()) {
checkerIconMap.put(checker, createCheckerIcon(checker));
}
setLayout(new GridLayout(ROW_COUNT, ROW_COUNT));
for (int row = 0; row < labelGrid.length; row++) {
for (int col = 0; col < labelGrid[row].length; col++) {
checkerGrid[row][col] = Checker.EMPTY;
JLabel gridCell = new JLabel(checkerIconMap.get(Checker.EMPTY));
gridCell.setOpaque(true);
gridCell.putClientProperty(ROW, row);
gridCell.putClientProperty(COLUMN, col);
Color c = row % 2 == col % 2 ? LIGHT_COLOR : DARK_COLOR;
gridCell.setBackground(c);
add(gridCell);
labelGrid[row][col] = gridCell;
}
}
for (int i = 0; i < labelGrid.length / 2 - 1; i++) {
for (int j = 0; j < labelGrid.length / 2; j++) {
int row = i;
int col = j * 2;
col += row % 2 == 0 ? 1 : 0;
labelGrid[row][col].setIcon(checkerIconMap.get(Checker.BLACK));
checkerGrid[row][col] = Checker.BLACK;
row = ROW_COUNT - row - 1;
col = ROW_COUNT - col - 1;
labelGrid[row][col].setIcon(checkerIconMap.get(Checker.RED));
checkerGrid[row][col] = Checker.RED;
}
}
MyMouseAdapter myMouseAdapter = new MyMouseAdapter();
addMouseListener(myMouseAdapter);
addMouseMotionListener(myMouseAdapter);
}
private Icon createCheckerIcon(Checker checker) {
BufferedImage img = new BufferedImage(SIDE_LENGTH, SIDE_LENGTH,
BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = img.createGraphics();
g2.setColor(checker.getColor());
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
int x = 3;
int y = x;
int width = SIDE_LENGTH - 2 * x;
int height = width;
g2.fillOval(x, y, width, height);
g2.dispose();
return new ImageIcon(img);
}
private class MyMouseAdapter extends MouseAdapter {
private int selectedRow = -1;
private int selectedCol = -1;
private Checker selectedChecker = null;
private JPanel glassPane = null;
private Point p = null;
private JLabel movingLabel = new JLabel(checkerIconMap.get(Checker.EMPTY));
public MyMouseAdapter() {
movingLabel.setSize(movingLabel.getPreferredSize());
movingLabel.setVisible(false);
}
@Override
public void mousePressed(MouseEvent e) {
p = e.getPoint();
for (int row = 0; row < labelGrid.length; row++) {
for (int col = 0; col < labelGrid[row].length; col++) {
JLabel gridCell = labelGrid[row][col];
if (gridCell == getComponentAt(p)) {
if (checkerGrid[row][col] != Checker.EMPTY) {
selectedRow = row;
selectedCol = col;
selectedChecker = checkerGrid[row][col];
checkerGrid[row][col] = Checker.EMPTY;
labelGrid[row][col].setIcon(checkerIconMap.get(Checker.EMPTY));
JRootPane rootPane = SwingUtilities.getRootPane(Checkers.this);
glassPane = (JPanel) rootPane.getGlassPane();
glassPane.setVisible(true);
glassPane.setLayout(null);
movingLabel.setIcon(checkerIconMap.get(selectedChecker));
movingLabel.setVisible(true);
glassPane.add(movingLabel);
int x = p.x - SIDE_LENGTH / 2;
int y = p.y - SIDE_LENGTH / 2;
movingLabel.setLocation(x, y);
}
}
}
}
}
@Override
public void mouseReleased(MouseEvent e) {
if (selectedChecker == null) {
return;
}
p = e.getPoint();
if (!Checkers.this.contains(p)) {
// if mouse releases and is totally off of the grid
returnCheckerToOriginalCell();
clearGlassPane();
return;
}
for (int row = 0; row < labelGrid.length; row++) {
for (int col = 0; col < labelGrid[row].length; col++) {
JLabel gridCell = labelGrid[row][col];
if (gridCell == getComponentAt(p)) {
if (isMoveLegal(row, col)) {
checkerGrid[row][col] = selectedChecker;
labelGrid[row][col].setIcon(checkerIconMap.get(selectedChecker));
// todo: check for jumped pieces...
} else {
// illegal move
returnCheckerToOriginalCell();
}
}
}
}
clearGlassPane();
}
// this code would go in the model class
private boolean isMoveLegal(int row, int col) {
if (checkerGrid[row][col] != Checker.EMPTY) {
// trying to put a checker on another checker
returnCheckerToOriginalCell();
} else if (row == selectedRow && col == selectedCol) {
// trying to put checker back in same position
returnCheckerToOriginalCell();
} else if (row % 2 == col % 2) {
// invalid square
returnCheckerToOriginalCell();
} else {
// TODO: more logic needs to go here to test for a legal move
// and to remove jumped pieces
return true;
}
return false;
}
@Override
public void mouseDragged(MouseEvent e) {
if (selectedChecker == null || p == null) {
return;
}
p = e.getPoint();
int x = p.x - SIDE_LENGTH / 2;
int y = p.y - SIDE_LENGTH / 2;
movingLabel.setLocation(x, y);
}
private void clearGlassPane() {
glassPane.setVisible(false);
movingLabel.setVisible(false);
selectedChecker = null;
p = null;
selectedCol = -1;
selectedRow = -1;
}
private void returnCheckerToOriginalCell() {
checkerGrid[selectedRow][selectedCol] = selectedChecker;
labelGrid[selectedRow][selectedCol].setIcon(checkerIconMap.get(selectedChecker));
}
}
private static void createAndShowGui() {
Checkers mainPanel = new Checkers();
JFrame frame = new JFrame("JLabelGrid");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class CheckerModel {
}
enum Checker {
EMPTY(new Color(0, 0, 0, 0)), RED(Color.red), BLACK(Color.black);
private Color color;
private Checker(Color color) {
this.color = color;
}
public Color getColor() {
return color;
}
}
更好的模型 - 视图示例正在进行...
答案 1 :(得分：0)
不是直接将新的Jlabel（）添加到数组中，而是首先创建一个实例，然后添加...我想这是在循环中完成的，例如：
JLabel lbl;
for(....) {
lbl = new JLabel(new JLabel((j+1)+":"+(i+1));
lbl.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent evt()){
// TODO here
}
});
BoardSquare.boardSquares[j][i].add(lbl);