gamedemo.java

图书中的经典例子 好好看看 会有帮助的。java2me版本的

//gameDemo.java file
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.game.*;
import java.util.*;

public class gameDemo extends MIDlet implements CommandListener
{
    private Command exitCommand;
    private DemoCanvas canvas;
    private DemoTask task ;
    private Timer timer;
    public gameDemo()
    {
        exitCommand =new Command("Exit",Command.EXIT,1);
        canvas =new DemoCanvas();
        canvas.addCommand(exitCommand);
        canvas.setCommandListener(this);
        timer = new Timer();
        task = new DemoTask(canvas);
    }
    protected void startApp(  ) throws MIDletStateChangeException
    {
        Display.getDisplay(this).setCurrent(canvas);
        timer.schedule(task, 0,100);
    }

    protected void pauseApp(  )
    {
    	timer.cancel();
    }

    protected void destroyApp( boolean p1 )
    {
    }

    public void commandAction(Command c,Displayable d)
    {
        if (c ==exitCommand)
        {
            destroyApp(false);
            notifyDestroyed();
        }
    }
    public class DemoCanvas extends GameCanvas
    {
    	private Graphics g;
    	private int[ ] clrs={0X00000000,0x00FF0000,0x0000FF00,0x000000FF};
    	private int curColor=0x00000000;
    	private int[ ] posXY={0,0, 20,0, 40,0, 0,20, 20,20, 40,20, 0,40, 20,40, 40,40};
    	private int curX=0,curY=0;
        public DemoCanvas() 
        {
        	super(true);
        	g = getGraphics();
        }
        public void Action()
        {
        	g.setColor(0x00FFFFFF);
        	g.fillRect(0,0,60,60);
        	int x,y;
        	int keyState = getKeyStates();
        	//判断ABCD键是否被按下
        	if((keyState & GAME_A_PRESSED) !=0)
        		curColor=clrs[0];
        	else if((keyState & GAME_B_PRESSED) !=0)
        		curColor=clrs[1];
        	else if((keyState & GAME_C_PRESSED) !=0)
        		curColor=clrs[2];
        	else if((keyState & GAME_D_PRESSED) !=0)
        		curColor=clrs[3];
        	//判断上下左右键是否被按下
        	if((keyState & UP_PRESSED) !=0)
        	{
        		curX = posXY[2];
        		curY = posXY[3];
        	}
        	else if((keyState & DOWN_PRESSED) !=0)
        	{
        		curX = posXY[14];
        		curY = posXY[15];
        	}
        	else if((keyState & LEFT_PRESSED) !=0)
        	{
        		curX = posXY[6];
        		curY = posXY[7];
        	}
        	else if((keyState & RIGHT_PRESSED) !=0)
        	{
        		curX = posXY[10];
        		curY = posXY[11];
        	}
        	else
        	{
        		curX = posXY[8];
        		curY = posXY[9];
        	}
        	g.setColor(curColor);
        	g.fillRect(curX,curY,20,20);
        	flushGraphics();
        	
        }
    }
    public class DemoTask extends TimerTask
    {
    	private DemoCanvas canvas;
    	public DemoTask(DemoCanvas can)
    	{
    		canvas = can;
    	}
    	public void run()
    	{
    		canvas.Action();
    	}
    }
}