java - JTextArea 不显示我告诉它的内容

Question

由于某种原因，我无法让 JTextArea“answersTA”显示任何内容。调用append() 和setText() 不会更新框中的信息。

这是我的程序的目标:接收一个字符串并将其存储到“word”，接收一个字符串并从中解析一个 int 并将其存储到“num”，将它们输入到solutions()方法中，然后显示solutions()返回的数组。我一生都无法展示任何东西。

public class CWGui extends JFrame
{
    private static final int WIDTH = 800;
    private static final int HEIGHT = 400;

    private JLabel pattern, number, answers;
    private JTextField patternTF, numberTF;
    private JButton execute, exitB;
    private JTextArea answersTA;

    //Button handlers:
    private ExecuteButtonHandler eHandler;
    private ExitButtonHandler ebHandler;

    public CWGui()
    {
        pattern = new JLabel("Enter the pattern: ", SwingConstants.RIGHT);
        number = new JLabel("Enter the number of solutions: ", SwingConstants.RIGHT);
        answers = new JLabel("Solutions: ", SwingConstants.LEFT);

        patternTF = new JTextField(10);
        numberTF = new JTextField(10);
        answersTA = new JTextArea();

        //SPecify handlers for each button and add (register) ActionListeners to each button.
        execute = new JButton("Execute");
        eHandler = new ExecuteButtonHandler();
        execute.addActionListener(ebHandler);
        exitB = new JButton("Exit");
        ebHandler = new ExitButtonHandler();
        exitB.addActionListener(ebHandler);

        setTitle("Crossword Solution Generator");
        Container pane = getContentPane();
        pane.setLayout(new GridLayout(4, 2));

        //Add things to the pane in the order you want them to appear (left to right, top to bottom)
        pane.add(pattern);
        pane.add(patternTF);
        pane.add(number);
        pane.add(numberTF);

        pane.add(execute);
        pane.add(exitB);

        pane.add(answers);
        pane.add(answersTA);


        setSize(WIDTH, HEIGHT);
        setVisible(true);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
    }

    private class ExecuteButtonHandler implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {

            try{
                String word = patternTF.getText(); 
                int num = Integer.parseInt(numberTF.getText());
                FileParser fp = new FileParser("TWL06.txt");
                List<String> dict = fp.getAllWords();

                CWSolution c = new CWSolution(dict);
                List<String> result = c.solutions(word,num);
                        answersTA.setText(result.toString());

            }
            catch(Exception t){}
        }
    }

    public class ExitButtonHandler implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {
            System.exit(0);
        }
    }

    public static void main(String[] args)
    {
        CWGui generator = new CWGui();
    }

}

Answer 1

确保对事件调度线程调用的 GUI 进行任何更新。该线程将更新 gui，因此不会卡住它，也正因为如此，请确保任何可能需要一段时间的进程都在 SwingWorker 线程上运行，该线程与 EDT 是分开的。 SwingWorker 线程可以在后台运行，同时还可以在此过程中为您提供更新。您可以在官方文档中获得对这些内容的详细描述。我最近才学会它，它很有帮助。