showOptionDialog选择了drawString选项

Question

我在JLabel内有一个JPanel，当我在showOptionDialog输入一些消息并选择＆＃34; OK＆＃34;按钮，JLabel应该打印出我输入的消息。但是，我所拥有的代码甚至没有进入paintComponent()类中的TextLabel方法（我使用了一个简单的跟踪语句来检查这一点）。我还尝试向MouseListener添加新的tagPanel，但它仍然无效。

我的程序代码太冗长，所以我只显示相关的代码。

主要类别：

//...list of global variables

public void go()
{       
    //...other codes

    image = new DrawLabel();
    imgPanel.add(image);
    imgPanel.setBorder(new LineBorder(Color.BLACK));
    image.addMouseListener(new MouseHandler());

    text = new TextLabel();
    tagPanel.add(text);
    tagPanel.setBorder(new LineBorder(Color.BLACK));
    tagPanel.setPreferredSize(new Dimension(200, 480));

    frame.add(imgPanel, BorderLayout.WEST);
    frame.add(tagPanel, BorderLayout.EAST);
    frame.setExtendedState(frame.getExtendedState() | JFrame.MAXIMIZED_BOTH);
    frame.setVisible(true);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}

MouseHandler类中的

showOptionDialog：

String[] options = {"OK"};
JPanel popOut = new JPanel();
JLabel lbl = new JLabel("Enter keywords: ");
JTextField txt = new JTextField(50);
popOut.add(lbl);
popOut.add(txt);
int selectedOption = JOptionPane.showOptionDialog(null, popOut, "Tag", JOptionPane.NO_OPTION, JOptionPane.QUESTION_MESSAGE, null, options , options[0]);

if(selectedOption == 0)
{
    String entered = txt.getText();
    String[] parts = entered.split(", ");

    for(int i=0; i<parts.length; i++)
    {
        keywords.add(parts[i]);
    }

}
else
{
    System.out.println("untitled");
}

TextLabel类：

private class TextLabel extends JLabel
{
    public void paintComponent(Graphics g)
    {
        if(keywords != null)
        {
            super.paintComponent(g);

            String words = "";

            for(int i=0; i<keywords.size(); i++)
            {
                words = words + keywords.get(i) + ", "; 
            }

            int fontSize = 20;
            g.setFont(new Font("TimesRoman", Font.PLAIN, fontSize));
            g.setColor(Color.BLACK);

            g.drawString(words, 50, 50);
            repaint();

            System.out.println("here");
        }
        else
        {
            super.paintComponent(g);
            repaint();
        }
    }
}