作者使用JBuilder2005，里面自带WTK2.1，自己下载2.2版本，2.2那个默认的模拟器看着实在爽。另外，Jbuilder X下的WTK也是2.0的版本。Jbuilder 9的WTK是1.04。首先开启Jbuilder。建立一个PRoject：
然后填写名字和路径。继续：
然后选择JDK路径，本身已有WTK2.1，你可以选择。但是你也可以自己选择其他的WTK版本:
点击jdk后面的路径按钮,继续:
next.工程建立完毕。接着点击file-New:
然后在对话框左边选择Micro，你就能看到右边出现MIDlet，Displayable。接上面的:如图示
点击MIDlet or Displayable,则让你输入MIDlet的名字.如图:
继续下一步，让你输入一个Displayable的名字，包括类型(form,canvas等)，是否自动加载Command等等。
然后Jbuilder自动生成所需代码,以及Jbuilder自加的一些东西。你可以添加或修改之。这里我将本站一篇关于介绍Gamecanvas的文章的代码拿过来,做少量修改,作为本文章的一个演示：
TestMIDlet.java文件:
package temps;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
/**
* Title:
*
* Description:
*
* Copyright: Copyright (c) 2005
*
* Company:
*
* @author not attributable
* @version 1.0
*/
public class TestMIDlet extends MIDlet
{
private Display display;
public void startApp()
{
try
{
display = Display.getDisplay(this);
Displayable1 gameCanvas = new Displayable1();
gameCanvas.start();
display.setCurrent(gameCanvas);
}
catch (Exception ex)
{
System.out.println(ex);
}
}
public Display getDisplay()
{
return display;
}
public void pauseApp()
{
}
public void destroyApp(boolean unconditional)
{
exit();
}
public void exit()
{
System.gc();
destroyApp(false);
notifyDestroyed();
}
}
Displayable1.java内容:
package temps;
import javax.microedition.lcdui.*;
import java.util.Random;
import javax.microedition.lcdui.game.*;
/**
*
Title:
*
* Description:
*
* Copyright: Copyright (c) 2005
*
* Company:
*
* @author not attributable
* @version 1.0
*/
public class Displayable1 extends GameCanvas implements Runnable
{
private boolean isPlay; // Game Loop runs when isPlay is true
private long delay; // To give thread consistency
private int currentX, currentY; // To hold current position of the 'X'
private int width; // To hold screen width
private int height; // To hold screen height
private Random random=new Random(System.currentTimeMillis());
private final int[] sequence={0,1,2,1,0,1,2,1,0,1,2,1,1,1,1,1,1};
private int counter=0;
private int enemyX,enemyY;
private int enemyDirect=0;
private boolean isdown=false;
private boolean isalive=true;
// Sprites to be used
private Sprite playerSprite;
private Sprite backgroundSprite;
private Sprite enemySprite;
// Layer Manager
private LayerManager layerManager;
// ConstrUCtor and initialization
public Displayable1() throws Exception
{
super(true);
width = getWidth();
height = getHeight();
currentX = width / 2;
currentY = height / 2;
enemyX=width/4;
enemyY=height/4;
delay = 100;
Image playerImage=null;
Image backgroundImage=null;
Image enemy=null;
// Load Images to Sprites
try
{
playerImage = Image.createImage("/transparent.png");
backgroundImage = Image.createImage("/background.png");
enemy=Image.createImage("/frames.png");
}
catch(Exception e)
{
System.out.println("get Image error!"+e.getMessage());
}
playerSprite = new Sprite(playerImage, 32, 32);
System.out.println(playerSprite.getRawFrameCount());
enemySprite=new Sprite(enemy,50,21);
backgroundSprite = new Sprite(backgroundImage);
layerManager = new LayerManager();
layerManager.append(playerSprite);
layerManager.append(enemySprite);
layerManager.append(backgroundSprite);
}
// Automatically start thread for game loop
public void start()
{
isPlay = true;
Thread t = new Thread(this);
t.start();
}
public void stop()
{
isPlay = false;
}
// Main Game Loop
public void run()
{
Graphics g = getGraphics();
while (isPlay == true)
{
input();
drawScreen(g);
try
{
Thread.sleep(delay);
}
catch (InterruptedException ie)
{
}
}
}
// Method to Handle User Inputs
private void input()
{
int keyStates = getKeyStates();
playerSprite.setFrame(0);
if(isalive)
{
if(counter==0)
{
enemyDirect=Math.abs(random.nextInt()%4);
}
counter++;
switch(enemyDirect)
{
case 0:
enemyY=Math.max(0,--enemyY);
break;
case 1:
enemyY=Math.min(++enemyY,height-enemySprite.getHeight());
break;
case 2:
enemyX=Math.max(0,--enemyX);
break;
case 3:
enemyX=Math.min(++enemyX,width-enemySprite.getWidth());
break;
}
counter=(counter++)%(sequence.length());
enemySprite.setFrame(sequence[counter]);
}
else
{
enemyY+=counter;
enemyY=Math.min(enemyY,height-enemySprite.getHeight());
if(enemyY
counter++;
enemySprite.setFrame(3);
}
// Left
if ((keyStates & LEFT_PRESSED) !
= 0)
{
currentX = Math.max(0, currentX - 1);
playerSprite.setFrame(1);
}
// Right
if ((keyStates & RIGHT_PRESSED) != 0)
if (currentX + 5
{
currentX = Math.min(width, currentX + 1);
playerSprite.setFrame(3);
}
// Up
if ((keyStates & UP_PRESSED) != 0)
{
currentY = Math.max(0, currentY - 1);
playerSprite.setFrame(2);
}
// Down
if ((keyStates & DOWN_PRESSED) != 0)
{
isdown=true;
}
if ((keyStates & DOWN_PRESSED) != 0)
{
if(isdown)
{
if (currentY + 10
{
currentY = Math.min(height, currentY + 1);
playerSprite.setFrame(4);
}
}
}
if((keyStates & FIRE_PRESSED)!=0)
{
isalive=!isalive;
counter=0;
}
if(!(enemyX+enemySprite.getWidth()
enemyY+enemySprite.getHeight()
enemyXcurrentX+playerSprite.getWidth()
enemyYcurrentY+playerSprite.getHeight()) && isalive)
{
counter=0;
isalive=false;
}
}
// Method to Display Graphics
private void
