imageitemdemo.java

来自「j2me学习 简单例子」· Java 代码 · 共 93 行

package example.demoseniorui.imageitem;

import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.ImageItem;
import javax.microedition.lcdui.Item;
import javax.microedition.lcdui.ItemCommandListener;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;

/**
 * <p>J2ME ImageItem Demo</p>
 * 
 * @author 刘光辉
 * @version 2009.02.01
 */
public class ImageItemDemo extends MIDlet 
	implements ItemCommandListener{

	private Display display;
	
	/**
	 * <p>ImageItemDemo的构造函数</p>
	 */
	public ImageItemDemo() {
		display = Display.getDisplay(this);
	}

	/**
	 * <p>启动程序,使MIDlet处于active状态</p>
	 * <p>在这个方法里声明了一个Form,用来放置ImageItem</p>
	 * <ul>ImageItem有两个构造函数,最常见的是需要五个参数的</ul>
	 * @see javax.microedition.midlet.MIDlet#startApp()
	 */
	protected void startApp() throws MIDletStateChangeException {
		Image img = null ;
		try{
			img = Image.createImage("/Icon.png");
		}catch(Exception e){
			e.printStackTrace();
		}
		Form f = new Form("ImageItem测试");
		f.append(img);
		
		ImageItem ii1 = new ImageItem("图片1",img,Item.LAYOUT_CENTER|Item.LAYOUT_NEWLINE_BEFORE,
				"图片1取代文字",Item.BUTTON);
		f.append(ii1);
		
		ImageItem ii2 = new ImageItem("图片2",img,Item.LAYOUT_RIGHT|Item.LAYOUT_NEWLINE_BEFORE,
				"图片2取代文字",Item.HYPERLINK);
		f.append(ii2);
		
		ImageItem ii3 = new ImageItem("图片3",img,Item.LAYOUT_LEFT|Item.LAYOUT_NEWLINE_BEFORE,
				"图片3取代文字",Item.PLAIN);
		f.append(ii3);
		
		display.setCurrent(f);
		
	}

	/**
	 * <p>暂停程序,使MIDlet处于pause状态</p>
	 * @see javax.microedition.midlet.MIDlet#pauseApp()
	 */
	protected void pauseApp() {

	}

	/**
	 * <p>销毁程序,使MIDlet处于destroyed状态</p>
	 * 
	 * @param boolean unconditional 
	 * <ul>true 释放资源保存数据进入destroyed状态,false 抛出异常保持当前状态</ul>
	 * @see javax.microedition.midlet.MIDlet#destroyApp(boolean)
	 */
	protected void destroyApp(boolean arg0) throws MIDletStateChangeException {

	}

	/**
	 * <p>命令处理函数,实现ItemCommandListener接口</p>
	 * @param Command cmd 命令对象
	 * @param Item Item 被放置到显示屏显示的Item对象
	 */
	public void commandAction(Command cmd, Item item) {
		System.out.println(cmd.getLabel());
		System.out.println(item.getLabel());
	}

}