Java--用单线程创建倒计时表

方法一:

package C5;

import java.awt.Color;
import java.awt.Font;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class CountdownTimer extends Thread {
    JTextField tf;
    JLabel l;
    JFrame fr;

    public void run() {
        buildGUI();
    }

    void display() {
        for (int i = 60; i >= 0; i--) {
            try {
                Thread.sleep(1000);
                String s = Integer.toString(i);

                tf.setText("   " + s + "second to go..");

            } catch (Exception e) {
                System.out.println(e);
            }
        }
        JOptionPane.showMessageDialog(fr, "Time up !!!!!!!!");
        tf.setText("");
        tf.setEditable(false);
    }

    public void buildGUI() {
        fr = new JFrame("Countown Timer");
        JPanel p = new JPanel();
        l = new JLabel("");
        tf = new JTextField(15);

        tf.setEnabled(false);
        Font f = new Font("Verdana", 0, 18);
        tf.setFont(f);
        tf.setBackground(Color.black);
        p.setBackground(Color.blue);
        fr.add(p);
        p.add(tf);
        p.add(l);
        fr.setVisible(true);
        fr.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        fr.setSize(300, 100);
        fr.setResizable(false);
        display();

    }

    public static void main(String args[]) {
        CountdownTimer obj = new CountdownTimer();
        // Thread countthread =new Thread();
        obj.start();
    }

}

方法二:

package C5;

import java.awt.Color;
import java.awt.Font;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class CountdownTimer implements Runnable {
    JTextField tf;
    JLabel l;
    JFrame fr;

    public void run() {
        buildGUI();
    }

    void display() {
        for (int i = 60; i >= 0; i--) {
            try {
                Thread.sleep(1000);
                String s = Integer.toString(i);

                tf.setText("   " + s + "second to go..");

            } catch (Exception e) {
                System.out.println(e);
            }
        }
        JOptionPane.showMessageDialog(fr, "Time up !!!!!!!!");
        tf.setText("");
        tf.setEditable(false);
    }

    public void buildGUI() {
        fr = new JFrame("Countown Timer");
        JPanel p = new JPanel();
        l = new JLabel("");
        tf = new JTextField(15);

        tf.setEnabled(false);
        Font f = new Font("Verdana", 0, 18);
        tf.setFont(f);
        tf.setBackground(Color.black);
        p.setBackground(Color.blue);
        fr.add(p);
        p.add(tf);
        p.add(l);
        fr.setVisible(true);
        fr.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        fr.setSize(300, 100);
        fr.setResizable(false);
        display();

    }

    public static void main(String args[]) {
        CountdownTimer obj = new CountdownTimer();
        Thread countthread =new Thread(obj);
        countthread.start();
    }

}

注：两个方法比较：

区别：

在继承thread类中：

 1.

2.

在建立runnable接口中：

1.

2

测试结果相同：