JAVA 跑马灯文字效果

JAVA跑马灯文字效果的实现：

1. 首先创建一个继承JFrame类的HorseRaceLightTextFrame窗体类，代码如下：

package com.example.horseracelighttext;

import java.awt.Dimension;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;

import javax.swing.JFrame;

public class HorseRaceLightTextFrame extends JFrame{

    /**
     * 
     */
    private static final long serialVersionUID = -1760723807752896879L;
    
    public HorseRaceLightTextFrame() {
        // TODO Auto-generated constructor stub
        this.addWindowListener(new WindowListener() {
            
            @Override
            public void windowOpened(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }
            
            @Override
            public void windowIconified(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }
            
            @Override
            public void windowDeiconified(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }
            
            @Override
            public void windowDeactivated(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }
            
            @Override
            public void windowClosing(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }
            
            @Override
            public void windowClosed(WindowEvent arg0) {
                // TODO Auto-generated method stub
                System.exit(0);
            }
            
            @Override
            public void windowActivated(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }
        });
        
        HorseRaceLightTextPanel panel = new HorseRaceLightTextPanel();
        this.add(panel);
        new Thread(panel).start();// 启动新线程
        this.setVisible(true);
    }
    
    public static void main(String[] args) {
        HorseRaceLightTextFrame frame = new HorseRaceLightTextFrame();
        frame.setDefaultCloseOperation(DISPOSE_ON_CLOSE);
        frame.setSize(360, 360);
    }

}

2. 在HorseRaceLightTextFrame窗体类中创建内部面板类，该面板类实现了Runnable接口，重写JComponent类中的paint()方法和实现Runnable类中的run()方法。在paint完成跑马灯文字的绘制；在run()方法中实现改变跑马灯文字的x坐标值。
3. 将内部面板类HorseRaceLightTextPanel的实例添加到HorseRaceLightTextFrame窗口中，进行跑马灯文字效果的显示。内部面板类HorseRaceLightTextPanel代码如下：

package com.example.horseracelighttext;

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

import javax.swing.JPanel;

/***
 * 跑马灯文字效果Panel
 * @author lenovo'
 *
 */
public class HorseRaceLightTextPanel extends JPanel implements Runnable {

    String value = "这是一个文字跑马灯范例，谢谢！";   //需要绘制的文字
    char[] drawChar = value.toCharArray();
    int[] x = new int[drawChar.length];   //绘制每个字符的x坐标
    int y = 100; //绘制文字的y坐标

    @Override
    public void paint(Graphics g) {
        // TODO Auto-generated method stub
        g.clearRect(0, 0, getWidth(), getHeight());  //清除绘制前上下文内容
        Font font = new Font("华文楷体", Font.BOLD, 20);  //创建字体样式对象
        g.setFont(font);   //设置字体样式
        g.setColor(Color.RED);  //设置字体颜色
        for (int j = drawChar.length - 1; j >= 0; j--) {
            g.drawString(drawChar[drawChar.length - 1 - j] + "", x[j], y);  //绘制字符
        }
    }

    @Override
    public void run() {
        // TODO Auto-generated method stub

        try {
            boolean flag = false;  //为false表示第一次执行，x坐标进行等比递增，否则进行等差递增
            while (true) {
                Thread.sleep(300);
                for (int i = drawChar.length - 1; i >= 0; i--) {
                    if (!flag) {
                        x[i] = x[i] + 20 * i;  //x坐标进行等比递增
                    } else {
                        x[i] = x[i] + 20;   //x坐标进行等差递增
                    }
                    
                    if (x[i] >= 360 -20) {  //大于窗体宽度-20时，坐标值为0
                        x[i] = 0;   
                    }
                    
                }
                repaint();  //重新绘制图像
                if (!flag) {
                    flag = true;
                }
            }
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

}

本文摘自：《JAVA开发实战1200例》---王家林