设置面板背景的 MouseClicked 事件答案

【问题标题】：MouseClicked event to setBackground of a panel设置面板背景的 MouseClicked 事件
【发布时间】：2013-06-05 05:08:20
【问题描述】：

我正在制作一个带有 9x12 面板的 GUI 配对猜谜游戏，每个面板都包含一个随机数。我已经做到了，所以当您将鼠标悬停在每个单独的面板上时，它会从红色变为黄色，一旦您的鼠标离开面板区域，它就会变回红色。我现在的问题是将单击的面板的颜色更改为绿色，并且将任何以前单击的面板变回原来的红色。它按预期变为绿色，但不知道如何在单击新面板后将先前单击的面板重置为红色。我希望有一个明显的答案，但这里有一些相关代码（未删减）：

public class NumberPanel extends JPanel {
    int rand;
    Random generator = new Random();
    JLabel numbers;
    boolean mouseEntered = false;
    boolean mouseClicked = false;
    boolean mouseUnClicked = false;
    MainPanel mp;


    public NumberPanel() {
        setBackground(Color.RED);
        setPreferredSize (new Dimension(40,40));            
        rand = generator.nextInt(8) +1;    
        addMouseListener(new NumberListener());    
    }

    public NumberPanel (MainPanel mp) {
         //Callback method for MainPanel
            this.mp = mp;
    }


    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        Font font = new Font("Verdana", Font.BOLD, 18);
        g.setFont(font);
        g.drawString("" +rand, 14,24);            
        if (mouseEntered) {
            setBackground(Color.YELLOW);
        }
        else {
            setBackground(Color.RED);
        }
        if (mouseClicked) {
            setBackground(Color.GREEN);
        } 
    }

    //represents the listener for mouse events
    private class NumberListener implements MouseListener {

        public void mouseEntered (MouseEvent event) {
            mouseEntered=true;
            repaint();
        }
        public void mouseExited(MouseEvent event) {
            mouseEntered=false;
            repaint();
        }
        public void mouseClicked(MouseEvent event) {
        }
        public void mouseReleased(MouseEvent event) {  
        }
        public void mousePressed(MouseEvent event) { 
            mouseClicked=true;
            repaint();
        }            
    }        
}

【问题讨论】：

“我现在的问题是..” ..形成一个问题？你的问题是什么？

标签： java swing awt mouselistener

【解决方案1】：

只需在NumberPanel 中创建一个名为current 的静态NumberPanel 字段：

private static NumberPanel current;

...
// create a static MouseListener instead of creating a new one for each
// NumberPanel instance.
private static final MouseAdapter mouseListener = new MouseAdapter(){

    public void mousePressed(MouseEvent event) {
        NumberPanel panel = (NumberPanel) event.getSource(); 
        if(current != null) { 
            current.mouseClicked = false;
        }
        current = panel;
        panel.mouseClicked = true;
        // repaint number panels container
    }
}
...
addMouseListener(mouseListener);

类似的东西应该跟踪当前点击的面板。

【讨论】：