我正在尝试创建一个带有开始停止和重置按钮的简单计时器。我是使用线程和 ActionListeners 的新手。我有这个工作，可以让我的计时器开始，我的按钮可以从开始到停止更改文本。但在那之后我被困住了。如果我按下开始按钮，我需要停止计时器，然后重新启动它。然后当然重置将其变回零。我不想使用java.util.Timer，我只想使用线程。一旦开始，我将如何让我的线程暂停然后恢复。我尝试使用内置方法，但无法正确编译。
import javax.swing.*;
import java.awt.Font;
import java.lang.String;
import java.awt.*;
public class Timer extends JPanel {
// Here are the fields from below!
private static JLabel label = new JLabel(" 0.00 seconds");
private static javax.swing.JButton start = new javax.swing.JButton("Start");
private static javax.swing.JButton reset = new javax.swing.JButton("reset");
/**
* Here is the Timer method- Begins with JLabel with medium alignment.
*/
public Timer() {
//new Thread(this).start();
//label = new JLabel(" 0.00 Seconds");
//this.label = label;
reset();
}
/**
* Here is the Reset method- pressing this button from below will
* stop the thread and reset the text.
*/
public static void reset() {
label.setFont(new Font("Arial",Font.BOLD,36));
label.setText(" 0.00 Seconds");
}
public static void startStop() {
//start.setText("stop");
//validate();
}
public static void countDown() {
int Msec=0,min=0,sec=0;
while(sec < 60) {
label.setText(min+":"+sec+":"+Msec);
//label.setLayout(new BorderLayout.CENTER);
//label.
Msec++;
if(Msec==60) {
Msec=0;
sec++;
//label.setText(min+":"+sec+":"+Msec);
}
if(sec ==60) {
Msec =0;
sec = 0;
min++;
}
try
{
Thread.sleep(10);
}
catch(Exception e)
{}
}
}
public static void main(String [] args) {
// we need a JFrame to put these elements into
javax.swing.JFrame win = new javax.swing.JFrame("Timer");
// here we are instantating a new timer
final Timer time = new Timer();
//Annonymous inner class
start.addActionListener(new java.awt.event.ActionListener() {
// here is the action performed method to start this.
public void actionPerformed(java.awt.event.ActionEvent e) {
//here we are creating a new thread to run throwable
// every click creates a new Thread ( so it goes faster)
String text = (String)e.getActionCommand();
if (text.equals("Start")){
start.setText("Stop");
}
else{
start.setText("Start");
}
Thread restart = new Thread(new Runnable() {
public void run() {
countDown();
//startStop();
}
});
restart.start();
}
});
//Look at the below abstract actionlistener below to get reset to work
javax.swing.JButton reset = new javax.swing.JButton("reset");
// here we are creating a new annonomys inner class.... check the
// curly braces
reset.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent e) {
Thread restart = new Thread(new Runnable() {
public void run() {
reset();
//Thread.stop();
}
});
restart.destroy();
}
});
//label.setVisible(true);
javax.swing.JPanel tb = new javax.swing.JPanel();
tb.add(reset);
tb.add(start);
//tb.add(circle);
win.add(tb,java.awt.BorderLayout.NORTH);
win.setSize(300,300);
//win.add(tb);
win.add(label,java.awt.BorderLayout.CENTER);
win.setDefaultCloseOperation(javax.swing.JFrame.DISPOSE_ON_CLOSE);
// hiding inside setVisible is borderLayout
win.setVisible(true);
}
}