Question

我想为每个按钮创建一个选择序列或创建一个内部类来处理每个按钮的事件点击。我的任务是单击一个按钮在文本框中显示或标记在界面中单击的按钮。

到目前为止，我制作了六个按钮和两个面板（每个面板中有三个按钮）。我仍然在努力建立一个内部阶级。我不知道如何使用ActionListener和ActionPerformed。我需要帮助使内部类在文本框中显示所选按钮。谢谢！

import java.awt.*;
import javax.swing.*;

public class PracticeEventDriven extends JFrame {

    public PracticeEventDriven()
    {
    JButton firstButton = new JButton("Button 1");
    JButton secondButton = new JButton("Button 2");
    JButton thirdButton = new JButton("Button 3");
    JButton fourthButton = new JButton("Button 4");
    JButton fifthButton = new JButton("Button 5");
    JButton sixthButton = new JButton("Button 6"); 

    /*Something is wrong with this. I want to use Button 4 to display.*/

    ActionListener listener = new ActionListener();
    fourthButton.addActionListener(listener);

        JPanel group1 = new JPanel();
        setLayout(new FlowLayout());

        group1.add(firstButton);
        group1.add(secondButton);
        group1.add(thirdButton);        

        JPanel group2 = new JPanel();
        setLayout(new FlowLayout());
        group2.add(fourthButton);
        group2.add(fifthButton);
        group2.add(sixthButton);

        this.getContentPane().add(group1);
        this.getContentPane().add(group2);


    }

    public static void main(String[] args)
    {
        PracticeEventDriven frame = new PracticeEventDriven();
        frame.setTitle("Button Panel Example");
        frame.setSize(600, 85);
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);

    }
}

Answer 1

为此，您需要在按钮上使用ActionListener。阅读有关ActionListener的教程，并阅读oracle docs。我已经改变了你的代码，检查它：

public class PracticeEventDriven extends JFrame {

    private JTextField field;

    public PracticeEventDriven() {
        field = new JTextField(10);
        JButton firstButton = new JButton("Button 1");
        JButton secondButton = new JButton("Button 2");
        JButton thirdButton = new JButton("Button 3");
        JButton fourthButton = new JButton("Button 4");
        JButton fifthButton = new JButton("Button 5");
        JButton sixthButton = new JButton("Button 6");

        ActionListener listener = new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent arg0) {
                JButton b = (JButton) arg0.getSource();
                field.setText(b.getText());
            }
        };
        firstButton.addActionListener(listener);
        secondButton.addActionListener(listener);
        thirdButton.addActionListener(listener);
        fifthButton.addActionListener(listener);
        fourthButton.addActionListener(listener);
        sixthButton.addActionListener(listener);

        JPanel group1 = new JPanel();
        setLayout(new FlowLayout());

        group1.add(firstButton);
        group1.add(secondButton);
        group1.add(thirdButton);

        JPanel group2 = new JPanel();
        setLayout(new FlowLayout());
        group2.add(fourthButton);
        group2.add(fifthButton);
        group2.add(sixthButton);

        this.getContentPane().add(group1);
        this.getContentPane().add(group2);
        this.getContentPane().add(field);
    }

    public static void main(String[] args) {
        PracticeEventDriven frame = new PracticeEventDriven();
        frame.setTitle("Button Panel Example");
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setVisible(true);

    }
}

创建选定的序列或内部类

1 个答案: