alphablending.java

AlphaBlending图片透明效果程序是利用j2me中MIDP2.0新特性Alpha混合来实现图片透明的两种演示效果代码

/**源代码由程序员联合开发网(www.pudn.com)会员"周润发"收集、整理、重新编辑
 *Email: [e-mail]
 *QQ号：1103798882
 *欢迎大家与我联系互相交流学习 
 **/
package AlphaPackage;

import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.StringItem;
import javax.microedition.midlet.MIDlet;

public class AlphaBlending extends MIDlet implements CommandListener {
    
    private Display display;
    private Form form;
    private Command exitCommand;
    private Command startCommand,viewCommand;
    private Command backCommand;
    private AlphaCanvas alphaCanvas;
    private TCanvas tcanvas=new TCanvas();
    
    private static final String IMAGE_NAME = "/pic/sky.jpg";
    
    
    public AlphaBlending() {
        display = Display.getDisplay(this);
        exitCommand = new Command("退出", Command.EXIT, 2);
        startCommand = new Command("效果1", Command.SCREEN, 1);
        viewCommand = new Command("效果2", Command.SCREEN, 1);
        backCommand = new Command("返回", Command.BACK, 1);
        alphaCanvas = new AlphaCanvas(IMAGE_NAME);
        form = new Form("Alpha半透明效果演示");
        form.append(new StringItem(null, "请选择菜单以显示不同的效果"));
        form.addCommand(exitCommand);
        form.addCommand(startCommand);
        form.addCommand(viewCommand);
        form.setCommandListener(this);
    }
    
    
    public void startApp() {
        display.setCurrent(form);    	
    }
    
    
    public void pauseApp() {}
    
    
    public void destroyApp(boolean unconditional) {}
    
    
    public void commandAction(Command c, Displayable d) {
        if (c == exitCommand) {
            destroyApp(false);
            notifyDestroyed();
        }else if (c == startCommand) {
            display.setCurrent(alphaCanvas);
            alphaCanvas.addCommand(backCommand);
            alphaCanvas.setCommandListener(this);
            
            Thread t = new Thread(alphaCanvas);
            t.start();
        }else if(c==viewCommand){
        	display.setCurrent(tcanvas);
        	tcanvas.addCommand(backCommand);
        	tcanvas.setCommandListener(this);
        }else if (c == backCommand) {            
            display.setCurrent(form);
        }
    }    
}