Java开发网 - 请教高手，背景颜色的不间断随机变化

Topic: 请教高手，背景颜色的不间断随机变化

1.请教高手，背景颜色的不间断随机变化

Posted by: flywithmoon
Posted on: 2004-08-24 22:40

以下代码无法实现面板背景颜色的不间断随机变化，请教高手如何修改：
import java.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
class test extends JFrame implements Runnable
{
  test(){
      Thread t=new Thread(this);
      this.getContentPane().add(new myp());
      t.start();
      }
  public static void main(String args []){
      test f=new test();
      f.setSize(300,300);
      f.show();
    }
  public void run()
  {
    while(true)
    {
      try{
      Thread.sleep(1500);repaint();
      System.out.print("hhh");
          }catch(Exception e){e.printStackTrace();}
      }
  }
}
class myp extends JPanel implements ActionListener
{
  JButton jb1,jb2,jb3,jb4;
  myp()
  {
    setLayout(new GridLayout(2,2));
    JPanel  p1=new JPanel();
    p1.setBackground(new Color((int)(Math.random()*255),(int)(Math.random()*255),(int)(Math.random()*255)));
    add(p1);jb1=new JButton("1");
    p1.add(jb1);
    JPanel  p2=new JPanel();
    p2.setBackground(new Color((int)(Math.random()*255),(int)(Math.random()*255),(int)(Math.random()*255)));
    add(p2);jb2=new JButton("2");
    p2.add(jb2);
    JPanel  p3=new JPanel();
    p3.setBackground(new Color((int)(Math.random()*255),(int)(Math.random()*255),(int)(Math.random()*255)));
    add(p3);jb3=new JButton("3");
    p3.add(jb3);
    JPanel  p4=new JPanel();
    p4.setBackground(new Color((int)(Math.random()*255),(int)(Math.random()*255),(int)(Math.random()*255)));
    add(p4);jb4=new JButton("4");
    p4.add(jb4);
    jb1.addActionListener(this);
    jb2.addActionListener(this);
    jb3.addActionListener(this);
    jb4.addActionListener(this);repaint();
  }

  public void actionPerformed(ActionEvent e) {
    Graphics g=getGraphics();
    if(e.getActionCommand().equals("1"))
      {
        g.setColor(new Color((int)(Math.random()*255),(int)(Math.random()*255),(int)(Math.random()*255)));
        g.fillRect(50,50,60,80);}
    if(e.getActionCommand().equals("2"))
    {
      g.setColor(new Color((int)(Math.random()*255),(int)(Math.random()*255),(int)(Math.random()*255)));
      g.fillArc(190,50,100,100,30,120);
      }
    if(e.getActionCommand().equals("3"))
    {
      g.setColor(new Color((int)(Math.random()*255),(int)(Math.random()*255),(int)(Math.random()*255)));
      g.fillOval(50,180,50,50);
      }
    if(e.getActionCommand().equals("4"))
    {
      g.setColor(new Color((int)(Math.random()*255),(int)(Math.random()*255),(int)(Math.random()*255)));
      g.drawString("Hello",200,200);
      }
    }
}

2.Re:请教高手，背景颜色的不间断随机变化 [Re: flywithmoon]	Copy to clipboard
Posted by: flywithmoon Posted on: 2004-08-26 09:25 斑竹哪里去了，怎么没人管了。

3.Re:请教高手，背景颜色的不间断随机变化 [Re: flywithmoon]

Copy to clipboard

Posted by: littledeer1974
Posted on: 2004-08-27 16:24

[code]
import java.awt.Color;
import java.awt.Container;
import java.awt.GridLayout;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;

class question01 extends JFrame {
question01() {
this.getContentPane().add(new MyPanel());

}

public static void main(String args[]) {
question01 f = new question01();
f.setSize(300, 300);
f.show();
}

}

class MyPanel extends JPanel implements Runnable {
JButton jb1, jb2, jb3, jb4;

JPanel panel1, panel2, panel3, panel4;

static int index = 0;

Container cont;

MyPanel() {
//
panel1 = new JPanel();
panel2 = new JPanel();
panel3 = new JPanel();
panel4 = new JPanel();
//
jb1 = new JButton("1");

jb2 = new JButton("2");

jb3 = new JButton("3");

jb4 = new JButton("4");
//

panel1.add(jb1);
panel2.add(jb2);
panel3.add(jb3);
panel4.add(jb4);

setLayout(new GridLayout(2, 2));

this.setNewColor();

this.add(panel1);
this.add(panel2);
this.add(panel3);
this.add(panel4);
Thread thread = new Thread(this);
thread.start();
}

public void setNewColor() {

//
panel1.setBackground(new Color((int) (Math.random() * 255), (int) (Math
.random() * 255), (int) (Math.random() * 255)));
panel2.setBackground(new Color((int) (Math.random() * 255), (int) (Math
.random() * 255), (int) (Math.random() * 255)));

panel3.setBackground(new Color((int) (Math.random() * 255), (int) (Math
.random() * 255), (int) (Math.random() * 255)));
panel4.setBackground(new Color((int) (Math.random() * 255), (int) (Math
.random() * 255), (int) (Math.random() * 255)));

}

public void run() {

while (true) {
try {
Thread.sleep(150);
this.setNewColor();
System.out.print("background color is changed!\n");
} catch (Exception e) {
e.printStackTrace();
}
}
}

}[/code]

不知道这个是不是你想要的效果

4.Re:请教高手，背景颜色的不间断随机变化 [Re: flywithmoon]	Copy to clipboard
Posted by: flywithmoon Posted on: 2004-08-27 16:55 请教一下，进程为什么必须放到主面板的构造里面，不能够放到主函数main里面，书上面就是放在main()里面的呀。

5.Re:请教高手，背景颜色的不间断随机变化 [Re: flywithmoon]	Copy to clipboard
Posted by: littledeer1974 Posted on: 2004-08-27 23:20 进程放到哪里都可以呀，看你怎么设计了，上边我觉得拿出来，整个程序结构会清晰一点，并不是什么规定，我想

6.Re:请教高手，背景颜色的不间断随机变化 [Re: flywithmoon]	Copy to clipboard
Posted by: littledeer1974 Posted on: 2004-08-27 23:25 补充以下，要改变的是Panel的属性，所以应该放到MyPanel　Class里比较好，放在主程序里，不太合适，因为主程序里还有生成实例的任务，那样有可能和Swing的线程冲突。

7.Re:请教高手，背景颜色的不间断随机变化 [Re: flywithmoon]	Copy to clipboard
Posted by: flywithmoon Posted on: 2004-08-30 10:39 谢谢了，是不是说在test类的Thread t=new Thread(this);中的this要换成new myp()

8.Re:请教高手，背景颜色的不间断随机变化 [Re: flywithmoon]	Copy to clipboard
Posted by: littledeer1974 Posted on: 2004-08-30 15:43 不是,你在参考一下上边给你的程序,县程的生成有两种方式,这是一种implemets Runnable interface 初学时理解起来有点怪,你还可以多参照一些参考书,加油哦