midlet2.java

这是郭克华老师的J2ME视频的源代码

package prj13_1;

import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.game.Sprite;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;

public class MIDlet2 extends MIDlet {
	private MyCanvas mc = new MyCanvas();
	private Display dis;
	protected void startApp() throws MIDletStateChangeException {
		dis = Display.getDisplay(this);
		mc.setTitle("按键画布");
		dis.setCurrent(mc);
	}

	protected void destroyApp(boolean arg0) throws MIDletStateChangeException {
		// TODO Auto-generated method stub

	}

	protected void pauseApp() {
		// TODO Auto-generated method stub

	}

	class MyCanvas extends Canvas{
		private Image img;
		private int x;
		private int y;
		private int TRANS = Sprite.TRANS_NONE;
		public MyCanvas(){
			try{
				img = Image.createImage("/img.png");
				x = 0;
				y = 0;
			}catch(Exception ex){}
		}
		public void paint(Graphics g){
			//画布清空
			g.setColor(0,0,255);
			g.fillRect(0,0,this.getWidth(),this.getHeight());
			g.drawRegion(img,0,0,img.getWidth(),img.getHeight(),TRANS,x,y,Graphics.LEFT|Graphics.TOP);
		}
		protected  void keyRepeated(int keyCode) {
			int action = this.getGameAction(keyCode);
			switch(action){
			case Canvas.UP:			y -= 5; 	break;
			case Canvas.DOWN:		y += 5; 	break;
			case Canvas.LEFT:		x -= 5; 	break;
			case Canvas.RIGHT:		x += 5; 	break;			
			}
			repaint();//调用paint函数重画
		}
		protected  void keyPressed(int keyCode) {
			int action = this.getGameAction(keyCode);
			if (action==Canvas.FIRE){
				switch(TRANS){
				case Sprite.TRANS_NONE:	TRANS = Sprite.TRANS_ROT90;	break;
				case Sprite.TRANS_ROT90:	TRANS = Sprite.TRANS_ROT180;	break;
				case Sprite.TRANS_ROT180:	TRANS = Sprite.TRANS_ROT270;	break;
				case Sprite.TRANS_ROT270:	TRANS = Sprite.TRANS_NONE;	break;
				}
			}
			repaint();//调用paint函数重画

		}
	}
	

}