一类的JButton如何将文本追加到另一类的JTextArea

Question

I'm trying to add my addText() method (or append() method) of JTextArea of one class to JButton located in another class.

I don't wanna to create new object in JButton or make method static, I have read some answers on this forum but I can't apply it to my code, so please help me to fix this code:

class Frame extends JFrame {
    public Frame() {
        TextArea textarea = new TextArea();
        Panel panel = new Panel();
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setPreferredSize(dim());
        setLayout(new BorderLayout());
        add(textarea, BorderLayout.CENTER);
        add(panel, BorderLayout.SOUTH);
        setVisible(true);
        pack();
        setLocationRelativeTo(null);
    }
    private Dimension dim() {
        Toolkit kit = Toolkit.getDefaultToolkit();
        Dimension d = kit.getScreenSize();
        int width = (int)(d.getWidth() / 2);
        int height = (int)(d.getHeight() / 2);
        return new Dimension(width, height);
    }
}
class TextArea extends JTextArea {
    public TextArea() {}
    public void addText(String s) {
        append(s);
    }
}
class Panel extends JPanel {
    public Panel() {
        Button button = new Button();
        button.setText("Start");
        button.addActionListener(new Button());
        add(button);
    }
    class Button extends JButton implements ActionListener {
        public Button() {}@Override
        public void actionPerformed(ActionEvent e) {}
    }
}

Answer 1

Use an anonymous class and delete the Button class. I do not see the need of having a class extending from JButton if you're already using JButton in your main code.

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Solution

button.addActionListener(new ActionListener(){
    @Override
    public void actionPerformed(ActionEvent e){
        // setText() or append();
    }
});