Java - JToggleButton - 虽然无限循环 - 无法单击按钮两次

Question

我需要请帮忙。我有一个 Java 代码，其中有一个小 GUI。我不能点击按钮两次。我只能激活 while 循环，但无法停用它。

这是我的代码:

import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;

public class Test2 {

public static void main(String[] args) {

    JFrame Frame = new JFrame("");
    Frame.setBounds(100, 100, 450, 300);
    Frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    Frame.setVisible(true);

    JPanel Panel = new JPanel();
    Frame.add(Panel);

    JToggleButton toggle = new JToggleButton("");
    Panel.add(toggle);
    toggle.setPreferredSize(new Dimension(50,50));
    toggle.addActionListener(new ActionListener() {


        public void actionPerformed(ActionEvent arg0) {
            int zufallszahl;
            if(toggle.isSelected()) {
                while(toggle.isSelected())      {

                zufallszahl = (int)(Math.random() * 10 +1);
                System.out.println(zufallszahl);
                }

            }               
        }
    }); 
}

}

Answer 1

您的问题在这里:

            while(toggle.isSelected())      {

                zufallszahl = (int)(Math.random() * 10 +1);
                System.out.println(zufallszahl);
            }

据我了解，您希望在选择按钮时生成随机数。要实现它，您需要 SwingWorker或 Timer .

这是一个带有计时器的示例:

import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JToggleButton;
import javax.swing.Timer;

public class Test2 {

    public static void main(String[] args) {

        JFrame frame = new JFrame("");
        frame.setBounds(100, 100, 450, 300);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);

        JPanel panel = new JPanel(new FlowLayout(FlowLayout.CENTER));
        frame.add(panel);

        final Timer timer = new Timer(300, new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                int zufallszahl = (int)(Math.random() * 10 +1);
                System.out.println(zufallszahl);
            }
        });
        final JToggleButton toggle = new JToggleButton("Go");
        panel.add(toggle);
        toggle.addActionListener(new ActionListener() {


            @Override
            public void actionPerformed(ActionEvent arg0) {
                if (toggle.isSelected()) {
                    timer.restart();
                } else {
                    timer.stop();
                }
            }
        }); 
    }

}