用java来实现滚动消息

最新推荐文章于 2021-03-01 23:55:12 发布

原创最新推荐文章于 2021-03-01 23:55:12 发布 · 1k 阅读

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文章标签：

#java #character #delay #null #thread #import

这是一个使用Java实现的滚动文字程序，通过Canvas、Thread和Graphics类实现。程序创建了一个字符串msg，设置滚动速度并启动线程，不断更新字符位置并重绘，当字符超出屏幕宽度时重新开始。此外，还包含窗口关闭事件监听，用于停止滚动并退出程序。

import java.awt.Canvas;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.JFrame;

class Test extends Canvas implements Runnable{

  // TODO Auto-generated method stub

  String msg;
  int msgLength;
  int x_character=0;
  Font wordFont;
  int width,height;

  Image offImg;
  Graphics offG;
  Thread runThread;
  static boolean stop;
  int delay;

public Test(int width,int height){
  this.width=width;
  this.height=height;
  first();
}
public void first(){
  wordFont=new Font("TimesRoman",Font.PLAIN+Font.BOLD,15);
  msg="小清要加油";
  msgLength=msg.length();

  delay=600;
  stop=false;
  runThread=new Thread(this);
  runThread.start();
}

public void run(){
  while(!stop){
   if(x_character++>=msgLength){
    x_character=0;
    offG=null;
   }
   repaint();
   try{
    Thread.sleep(delay);
   }catch(InterruptedException e){

   }
  }
}
public void paint(Graphics g){
  g.setFont(wordFont);
  g.setColor(Color.red);
  g.drawString(msg.substring(0,x_character),10, height/2);
}
public void update(Graphics g){

  if(offG!=null){
   paint(offG);
   g.drawImage(offImg,0,0,this);
  }else{
   paint(g);
   offImg=createImage(width,height);
   offG=offImg.getGraphics();
  }
}
public static void stop(){
  stop=true;
}
public static void main(String[] args){

  int width=200;
  int height=100;
  Test test=new Test(width,height);
  JFrame frame=new JFrame("滚动的消息");

  frame.setLocation(0,0);
  frame.setSize(width,height);

  frame.addWindowListener(new WindowAdapter(){
   public void windowClosing(WindowEvent e){

    Test.stop();
    System.exit(0);
   }
  });
  frame.getContentPane().add(test);
  frame.setVisible(true);

}
}