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首先先给出本例的效果图：

首先，需要说明一下LWUIT的控件：
    LWUIT的控件，可以算是做得很全，他的设计模式跟J2SE有点类似，而做过J2ME的人要掌握也不需要长时间。LWUIT的控件，是原来高级控件与低级控件的集合，并加入了更多元素，因此你可以在用高级控件的同时，很自然地实现低级控件的功能。例如本文中的绘图功能，就是如此！
    在本例中，依然使用大家熟悉的void paint(Graphics g) 函数，作为绘图的主体，然而paint的“上司”(绘图类)并不再是继承Canvas，而是继承Component，并且继承Component之后要这样被调用：form.addComponent(BorderLayout.CENTER, new Painting());//Painting就是“上司”。可见，在LWUIT里，已经没低级控件这个概念，但是有这个用法-----传统的绘图类也作为控件类，被调用了。或许，你想用回原来的javax.microedition.lcdui.Graphics，但是lcdui的Graphics和Display 与 LWUIT的Graphics和Display不兼容(LWUIT多了很多方法)，因此“新欢旧爱不能兼得”！
    
OK,先给出调用绘图功能的代码：

    private class ButtonActionListener implements ActionListener {
        public void actionPerformed(ActionEvent evt) {
          String sel_button=((Button)(evt.getSource())).getText();//取得所选按钮的名称
          if(sel_button.equals("Image 1"))
              new AnimationDemo().form.show();
          else if(sel_button.equals("Image 2"))
              new PaintingDemo().form.show();
        }
    }接着再给出绘图功能实现的代码：
/*
* Copyright ?2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*
*/
package com.sun.lwuit.uidemo;
import com.sun.lwuit.Command;
import com.sun.lwuit.Component;
import com.sun.lwuit.Form;
import com.sun.lwuit.Graphics;
import com.sun.lwuit.events.ActionEvent;
import com.sun.lwuit.events.ActionListener;
import com.sun.lwuit.layouts.BorderLayout;
/**
* Demonstrates simple animation both static and manual
*
* @author Shai Almog
*/
public class PaintingDemo   extends Form implements ActionListener {
    public Form form = new Form("PaintingDemo");
    private  Command backCommand = new Command("Back", 1);
    private  Command nextCommand = new Command("next", 2);
    PaintingDemo()
    {
            form.addCommand(backCommand);
            form.addCommand(nextCommand);
            form.setCommandListener(this);
            form.setLayout(new BorderLayout());
            form.addComponent(BorderLayout.CENTER, new Painting());
    }
  public class Painting extends Component{
        private int w;
   public void paint(Graphics g) {
          g.setColor(0x000000);
          g.fillRect(0, 0, this.getWidth(), this.getHeight());
          w = getWidth();
          drawSqrt1(g);
          g.setColor(0xffffff);
          g.drawString("hellogv", 12, 33);
      }
           private void drawSqrt1(Graphics g) {
            long start = System.currentTimeMillis();
            int centerY1 = 50;
            //绘制X轴
            //设置绘图颜色为蓝色
            g.setColor(0x0000FF);
            g.drawLine(0, centerY1, w, centerY1);
            //设置绘图颜色为白色
            g.setColor(0xFFFFFF);
            int oldX = 0;
            int oldY1 = centerY1;
            int y1;
            for(int i=1;i
                //              放大3倍
                y1 = centerY1 - (int)(3*Math.sqrt(i));
                g.drawLine(oldX, oldY1, i, y1);
                oldX = i;
                oldY1 = y1;
            }
            long time = System.currentTimeMillis() - start;
            System.out.println("drawSqrt1 Runtime: " + time);
        }
  }
    public void actionPerformed(ActionEvent arg0) {
        if(arg0.getCommand()==backCommand)
        {
            UIDemoMIDlet.backToMainMenu();
        }
        else if(arg0.getCommand()==nextCommand)
        {
          
        }
    }
}OK，还是那句，希望大家多多支持LWUIT，让它可以做得更加好！
本文来自：http://blog.csdn.net/hellogv/ ，转载必须注明出处！