昨天培训讲了JPanel的paint方法，突然想到以前看到过滚动字幕是靠paint方法做的，于是乎又是各种百度找模版，写了个滚动字幕的Panel。

做的是左右来回滚动的那种。

package com.raikou.MusicPlayer;import java.awt.Graphics;import java.awt.Graphics2D;import java.awt.RenderingHints;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import javax.swing.JPanel;import javax.swing.Timer;public class PanelTitle extends JPanel {    private static final long serialVersionUID = 1L;    private String message = " ";    private int xCoordinate = 0;    private int yCoordinate = 10;    private int count=0;    private boolean flag = false;    private int delay = 0;        public PanelTitle(String message) {        this.message = message;                Timer timer = new Timer(100, new TimerListener());        timer.start();    }        public void restr(String message)    {        this.message = message;        xCoordinate = 0;            }        public void paintComponent(Graphics g)    {        super.paintComponent(g);        yCoordinate = getHeight()/2 + 4;        //System.out.println(getWidth());        Graphics2D g2 = (Graphics2D)g;        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);        //System.out.println( message.getBytes().length);        int textWidth = getFontMetrics(g2.getFont()).bytesWidth(message.getBytes(), 0, message.getBytes().length);        //System.out.println(textWidth);                if(!flag)        {
    //设置字符串到达最左端或最右端时停留3秒            delay++;            if(delay>30)            {                flag = true;                delay = 0;            }        }        else        {        if (textWidth > getWidth())        {            if(xCoordinate>=-(textWidth-getWidth()+5)&&count%2==0)            {                xCoordinate -= 2;                if(xCoordinate <=-(textWidth-getWidth()+5))                {                    count++;                    flag = false;                }            }                        else                if(xCoordinate <= 5 && count%2!=0)                {                    xCoordinate += 2;                    if(xCoordinate >= 5)                    {                        count++;                        flag = false;                    }                }        }        }        g.drawString(message, xCoordinate, yCoordinate);    }    class TimerListener implements ActionListener    {        public void actionPerformed(ActionEvent e)        {            repaint();        }    }}