JAVA需要一条秒表计时器代码

好吧，已看到你的评论,我在这里再回答一次：

1）你所说的置顶如果是属于悬浮窗效果，那么JFrame实例化后，再添加一行如下的代码：

form1.setAlwaysOnTop(true)// 总是允许窗口置顶

2)时分秒更简单了，除一除转转换就行了，没有技术含量。

3)快捷键通过JButton类的setMnemonic方法实现

So,综上，整个程序的实现算法如下：

package hky.example

import java.awt.BorderLayout

import java.awt.Container

import java.awt.GridLayout

import java.awt.event.ActionEvent

import java.awt.event.ActionListener

import java.awt.event.KeyEvent

import java.awt.event.WindowEvent

import java.awt.event.WindowListener

import java.io.*

import java.util.*

import javax.swing.JButton

import javax.swing.JFrame

import javax.swing.JOptionPane

import javax.swing.JPanel

import javax.swing.JTextField

import javax.swing.plaf.OptionPaneUI

public class Demo{

    static boolean isRuning=false

    static boolean isFirst=true

    static Integer hmsCounter=0

    static int hour,minute,second

    

    @SuppressWarnings("unchecked")

    public static void main(String[] args) throws Exception {

 

        JFrame form1 = new JFrame("Form1")

        form1.setAlwaysOnTop(true)// 1)总是允许窗口置顶

        

        JTextField jTextField = new JTextField(10)

        jTextField.setSize(10, 10)

        jTextField.setText("0")

        jTextField.setEditable(false)

 

        JButton jButton = new JButton("开始")

        jButton.setSize(10, 10)

 

        

        Thread thread = new Thread(new Runnable() {

            @Override

   举者       困答笑  public void run() {

                while (true) {

    汪含                while(isRuning){

                     ++hmsCounter 

                     //3)时分秒显示

                     hour=hmsCounter/3600

                     minute=hmsCounter%3600/60

                     second=hmsCounter%60

                        jTextField.setText(hour+"时"+minute+"分"+second+"秒")

                        try {Thread.sleep(1000)} catch (Exception e2) {}

                    }

                    try {Thread.sleep(200)} catch (Exception e2) {}// 修复上一次回答的版本可能会存在的Bug

                }

            }

        })

        jButton.setMnemonic(KeyEvent.VK_ENTER)// 2)给JButton发送 Alt+Enter快捷键

        jButton.addActionListener(new ActionListener() {

            @Override

            public void actionPerformed(ActionEvent e) {

               String text=jButton.getText().equals("开始")?"暂停":"开始"

               jButton.setText(text)

               isRuning=!isRuning

               if(isFirst){

                   thread.start()

                   isFirst=false

               }

            }

        })

 

        JPanel panel = new JPanel()

        panel.setSize(200, 200)

        panel.add(jTextField, BorderLayout.NORTH)

        panel.add(jButton, BorderLayout.CENTER)

        form1.add(panel)

        form1.setBounds(200, 100, 250, 150)

        form1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE)

        form1.addWindowListener(new WindowListener() {

            @Override

            public void windowOpened(WindowEvent e) {

                // TODO Auto-generated method stub

                 

            }

             

            @Override

            public void windowIconified(WindowEvent e) {

                // TODO Auto-generated method stub

                 

            }

             

            @Override

            public void windowDeiconified(WindowEvent e) {

                // TODO Auto-generated method stub

                 

            }

             

            @Override

            public void windowDeactivated(WindowEvent e) {

                // TODO Auto-generated method stub

                 

            }

             

            @Override

            public void windowClosing(WindowEvent e) {

               // 窗口关闭前取出文本框的数字保存到外部文件，代码在此处写

                JOptionPane.showMessageDialog(null, "Are you sure closing?")

            }

             

            @Override

            public void windowClosed(WindowEvent e) {

                // TODO Auto-generated method stub

                 

            }

             

            @Override

            public void windowActivated(WindowEvent e) {

                // TODO Auto-generated method stub

                 

            }

        })

        

        form1.setVisible(true)

    }

}

package demo

import javax.swing.*

import java.awt.HeadlessException

import java.awt.BorderLayout

import java.awt.FlowLayout

import java.awt.Font

import java.awt.event.ActionListener

import java.awt.event.ActionEvent

public class Timer extends JFrame {

private static final long serialVersionUID = 1L

private static final String INITIAL_LABEL_TEXT = "00:00:00 000"

// 计数线程

private CountingThread thread = new CountingThread()

// 记录程序开始时间

private long programStart = System.currentTimeMillis()

// 程序旁并戚一开始就是暂停的蔽尘

private long pauseStart = programStart

// 程序暂停的总时间

private long pauseCount = 0

private JLabel label = new JLabel(INITIAL_LABEL_TEXT)

private JButton startPauseButton = new JButton("开始")

private JButton resetButton = new JButton("清零")

private ActionListener startPauseButtonListener = new ActionListener() {

public void actionPerformed(ActionEvent e) {

if (thread.stopped) {

pauseCount += (System.currentTimeMillis() - pauseStart)

thread.stopped = false

startPauseButton.setText("暂停")

} else {

pauseStart = System.currentTimeMillis()

thread.stopped = true

startPauseButton.setText("继续")

}

}

}

private ActionListener resetButtonListener = new ActionListener() {

public void actionPerformed(ActionEvent e) {

pauseStart = programStart

pauseCount = 0

thread.stopped = true

label.setText(INITIAL_LABEL_TEXT)

startPauseButton.setText("开始")

}

}

public Timer(String title) throws HeadlessException {

super(title)

setDefaultCloseOperation(EXIT_ON_CLOSE)

setLocation(300, 300)

setResizable(false)

setupBorder()

setupLabel()

setupButtonsPanel()

startPauseButton.addActionListener(startPauseButtonListener)

resetButton.addActionListener(resetButtonListener)

thread.start()// 计数线程运陵一直就运行着

}

// 为窗体面板添加边框

private void setupBorder() {

JPanel contentPane = new JPanel(new BorderLayout())

contentPane.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5))

this.setContentPane(contentPane)

}

// 配置按钮

private void setupButtonsPanel() {

JPanel panel = new JPanel(new FlowLayout())

panel.add(startPauseButton)

panel.add(resetButton)

add(panel, BorderLayout.SOUTH)

}

// 配置标签

private void setupLabel() {

label.setHorizontalAlignment(SwingConstants.CENTER)

label.setFont(new Font(label.getFont().getName(), label.getFont().getStyle(), 40))

this.add(label, BorderLayout.CENTER)

}

// 程序入口

public static void main(String[] args) {

try {

UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName())

} catch (Exception e) {

e.printStackTrace()

}

Timer frame = new Timer("计时器")

frame.pack()

frame.setVisible(true)

}

private class CountingThread extends Thread {

public boolean stopped = true

private CountingThread() {

setDaemon(true)

}

@Override

public void run() {

while (true) {

if (!stopped) {

long elapsed = System.currentTimeMillis() - programStart - pauseCount

label.setText(format(elapsed))

}

try {

sleep(1) // 1毫秒更新一次显示

} catch (InterruptedException e) {

e.printStackTrace()

System.exit(1)

}

}

}

// 将毫秒数格式化

private String format(long elapsed) {

int hour, minute, second, milli

milli = (int) (elapsed % 1000)

elapsed = elapsed / 1000

second = (int) (elapsed % 60)

elapsed = elapsed / 60

minute = (int) (elapsed % 60)

elapsed = elapsed / 60

hour = (int) (elapsed % 60)

return String.format("%02d:%02d:%02d %03d", hour, minute, second, milli)

}

}

}

你可以试试，希望能帮到你！

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