Question

我的程序中有三个按钮和一个JTextArea。我想要做的是，当用户按下按钮时，我希望JTextArea具有按下按钮1的文本，按下按钮2等等。例如。

JButton button1 = new JButton();
JButton button2 = new JButton();
JButton button3 = new JButton();

JTextArea text = new JTextArea();
JFrame frame = new JFrame();
frame.add(button1);
frame.add(button2);
frame.add(button3);
frame.add(text);
frame.setVisible(true);

我想要做的是，当用户按下按钮1时，我希望JTextArea具有按下按钮1的文本，然后如果用户按下按钮2，我希望JTextArea具有先前的文本和按钮2的文字。所以它应该说像;

button 1 was pressed
button 2 was pressed

编辑：

所以有这样的文字，

button 1 was pressed button 2 was pressed
button 3 was pressed

如果我有更多按钮，它将看起来像这样

button 1 was pressed button 2 was pressed
button 3 was pressed button 4 was pressed
button 5 was pressed button 6 was pressed

等等。

Answer 1

您需要向按钮添加动作侦听器，如下所示：

button1.addActionListener(new ActionListener() {

    @Override
    public void actionPerformed(ActionEvent arg0) {
        textArea.append("button 1 was pressed");

    }
});

别忘了在班级声明textArea。

希望这有帮助

Answer 2

将actionListener添加到将调用的每个按钮

yourTextArea.append("button X was pressed\n");

这是一个简单的演示

JFrame frame = new JFrame();
frame.setLayout(new FlowLayout());

final JTextArea area = new JTextArea(2,20);
frame.getContentPane().add(area);

JButton button1 = new JButton("press me");
JButton button2 = new JButton("press me");

button1.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        area.append("button 1 was pressed\n");
    }
});
button2.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        area.append("button 2 was pressed\n");
    }
});

frame.getContentPane().add(button1);
frame.getContentPane().add(button2);

frame.setSize(300,300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);

您也可以使用

try {
    area.getDocument().insertString(0,"button 1 was pressed\n", null);
} catch (BadLocationException e1) {
    e1.printStackTrace();
}

而不是

yourTextArea.append("button X was pressed\n");

如果要在文本区域的开头添加新行。

Answer 3

在将按钮添加到框架之前，请执行以下操作：

button.addActionListener（new ActionListener（）{

        public void actionPerformed(ActionEvent e)
        {
            //Here write what you want to be execute when button is pressed
        }
    });

有关此次访问的更多详情：http://docs.oracle.com/javase/tutorial/uiswing/events/actionlistener.html

如何将文本添加到JTextArea？ java的

3 个答案: