Swing 按钮重绘问题答案

【问题标题】：Swing button repaint issueSwing 按钮重绘问题
【发布时间】：2010-04-16 01:39:35
【问题描述】：

我是 Java 新手，我必须在周日之前完成一个学校项目，但遇到了问题。

代码如下：

private abstract class GamePanel {
    JPanel panel = null;
}

private class PutPanel extends GamePanel {

    JButton putShip1 = new JButton("");
    JButton putShip2 = new JButton("");
    JButton putShip3 = new JButton("");
    JButton putShip4 = new JButton("");

    ShipDirection ship1Direction = ShipDirection.NORTH;
    ShipDirection ship2Direction = ShipDirection.NORTH;
    ShipDirection ship3Direction = ShipDirection.NORTH;
    ShipDirection ship4Direction = ShipDirection.NORTH;



    JButton startButton = new JButton("Start game");

    public PutPanel(){
        this.panel = new JPanel();
        panel.setSize(200, Torpedo.session.map.size*Field.buttonSize+300);

        panel.setBackground(Color.blue);

        putShip1.setSize(90, 90);
        putShip1.setLocation(55, 5);
        putShip1.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship1/full_north.png", null));

        putShip2.setSize(90, 90);
        putShip2.setLocation(55, 105);
        putShip2.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship2/full_north.png", null));

        putShip3.setSize(90, 90);
        putShip3.setLocation(55, 205);
        putShip3.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship3/full_north.png", null));

        putShip4.setSize(90, 90);
        putShip4.setLocation(55, 305);
        putShip4.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship4/full_north.png", null));

        startButton.setSize(150, 30);
        startButton.setLocation(20, Torpedo.session.map.size*Field.buttonSize+205);

        panel.add(putShip1);
        panel.add(putShip2);
        panel.add(putShip3);
        panel.add(putShip4);
        panel.add(startButton);

        startButton.addActionListener(startButton());
        startButton.addActionListener(putShip1());
        startButton.addActionListener(putShip2());
        startButton.addActionListener(putShip3());
        startButton.addActionListener(putShip4());

        panel.setLayout(null);
        panel.setVisible(true);
    }

    private ActionListener startButton(){
        return new ActionListener(){
             public void actionPerformed(ActionEvent e) {
                 putPanel.panel.setVisible(false);
                 actionPanel.panel.setVisible(true);
             }
        };

    }

    private ActionListener putShip1(){
        return new ActionListener(){
             public void actionPerformed(ActionEvent e) {
                 selectedShip = 1;
                 putShip1.setBackground(Color.red);
                 putShip2.setBackground(null);
                 putShip3.setBackground(null);
                 putShip4.setBackground(null);
                 switch(ship1Direction){
                    case NORTH: ship1Direction = ShipDirection.EAST;
                                putShip1.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship1/full_east.png", null));
                                break;
                    case EAST:  ship1Direction = ShipDirection.SOUTH;
                                putShip1.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship1/full_south.png", null));
                                break;
                    case SOUTH: ship1Direction = ShipDirection.WEST;
                                putShip1.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship1/full_west.png", null));
                                break;
                    case WEST:  ship1Direction = ShipDirection.NORTH;
                                putShip1.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship1/full_north.png", null));
                                break;
                 }
                 putShip1.repaint();
                 putShip2.repaint();
                 putShip3.repaint();
                 putShip4.repaint();
                 panel.repaint();
                 JOptionPane.showMessageDialog(new JFrame(), "Repaint finished", "Repaint status info", JOptionPane.INFORMATION_MESSAGE); //this here hangs the program when the method is finally called
             }
        };

当点击其中一个 putShip* 按钮时，它应该将自己的图标向右旋转 90°（意味着将其更改为下一个图像），但在单击 startButton 之前它什么也不做，这会将面板更改为另一个. （这里只有第一个按钮的 actionListener ，其他的几乎一样）。该面板位于一个 JFrame 中，其中还有两个尚未执行任何操作的面板。

我怎样才能让它正常工作？

谢谢。

【问题讨论】：

那是因为你没有将监听添加到除了startButton之外的其他按钮
Ohshit :D 那一定很晚了...谢谢 :P
@Chuk Lee 你应该把它作为答案，以便它可以被接受。

标签： java swing button repaint actionlistener

【解决方案1】：

正如用户 Chuk Lee 所说，也将 ActionListeners 添加到 putShip* 按钮。这里有一点代码供您添加：

    startButton.addActionListener(startButton());
    startButton.addActionListener(putShip1());
    startButton.addActionListener(putShip2());
    startButton.addActionListener(putShip3());
    startButton.addActionListener(putShip4());

    putShip1.addActionListener(putShip1());
    putShip2.addActionListener(putShip2());
    putShip3.addActionListener(putShip3());
    putShip3.addActionListener(putShip3());

    panel.setLayout(null);
    panel.setVisible(true);

【讨论】：