colorcontrol.java

一本介绍手机游戏开发的书中的源代码

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

public class colorControl extends MIDlet
{
   Display display;
   canvasColor canvascolor;

   public colorControl()
   {
      canvascolor=new canvasColor();
      display=Display.getDisplay(this);
   }

   public void startApp()
   {
      display.setCurrent(canvascolor);
   }

   public void pauseApp(){}

   public void destroyApp(boolean unconditional){}

   class canvasColor extends Canvas 
   {
      int     gameaction=0;
      int     red=150;
      int     green=150;
      int     blue=150;
      int     colorType=0;
      Image   handImage;

      public canvasColor()
      {
         try{
             handImage=Image.createImage("/hand.png");
         }catch(Exception ex){}
      }
      
      public void keyPressed(int keyCode) 
      {
         gameaction=getGameAction(keyCode);
         switch(gameaction)
         {
            case UP:
                 if(colorType==0)
                 {
                    red++;
                    if(red>255) red=255;
                 } 
                  else if(colorType==1){
                    green++;
                    if(green>255) green=255;
                 }
                  else{
                    blue++;
                    if(blue>255) blue=255;
                 }
                 repaint();
                 break;
            case DOWN:
                 if(colorType==0)
                 {
                   red--;
                   if(red<0) red=0;
                 } 
                  else if(colorType==1){
                    green--;
                    if(green<0) green=0;
                 }
                  else{
                    blue--;
                    if(blue<0) blue=0;
                 }
                 repaint();
                 break;
            case LEFT:
                 colorType--;
                 if(colorType<0) colorType=0;
                 repaint();
                 break;
            case RIGHT:
                 colorType++;
                 if(colorType>2) colorType=2;
                 repaint();                 
                 break;
          }
      }

      public void paint(Graphics g)
      {
         g.setColor(red, green, blue);
         g.fillRect(0,0,getWidth(),getHeight());
         g.setColor(0);
         g.drawString("游戏界面数值表", getWidth()/2, 20, Graphics.HCENTER | Graphics.TOP);
         g.drawString("请按上、下键选择颜色数值", getWidth()/2, 50, Graphics.HCENTER | Graphics.TOP);
         g.drawString(String.valueOf(red), getWidth()/4, 100, Graphics.HCENTER | Graphics.TOP);
         g.drawString("红色", getWidth()/4, 120, Graphics.HCENTER | Graphics.TOP);
         g.drawString(String.valueOf(green), 2*getWidth()/4, 100, Graphics.HCENTER | Graphics.TOP);
         g.drawString("绿色", 2*getWidth()/4, 120, Graphics.HCENTER | Graphics.TOP);
         g.drawString(String.valueOf(blue), 3*getWidth()/4, 100, Graphics.HCENTER | Graphics.TOP);
         g.drawString("蓝色", 3*getWidth()/4, 120, Graphics.HCENTER | Graphics.TOP);
         g.drawImage(handImage, (colorType+1)*getWidth()/4, 130, Graphics.HCENTER | Graphics.TOP);
      }
   }
}