/*
* stringItemlet.Java
*
* Created on 2005年4月14日, 下午4:26
*/
import Javax.microedition.midlet.*;
import Javax.microedition.lcdui.*;
/**
*
* @author Administrator
* @version
*/
public class stringItemlet extends MIDlet implements CommandListener,
ItemCommandListener{
private Form aform;
private Command okCommand;
private Command exitCommand;
private Command hllinkCommand;
private Command bCommand;
private Display aDisplay;
private StringItem hlstringItem;
private StringItem bstringItem;
private Alert hlAlert;
private Alert bAlert;
public stringItemlet(){
okCommand=new Command("OK",Command.OK,1);
exitCommand=new Command("EXIT",Command.EXIT,1);
hllinkCommand=new Command("LINK",Command.ITEM,2);
bCommand=new Command("BUTTON",Command.ITEM,2);
aform=new Form("StringItemTest");
//if click hyperlink "here",display anAlert
hlstringItem=new StringItem(null,"here",Item.HYPERLINK);
hlstringItem.setItemCommandListener(this);
hlstringItem.setDefaultCommand(hllinkCommand);
bstringItem=new StringItem(null,"Available?",Item.BUTTON);
bstringItem.setItemCommandListener(this);
bstringItem.setDefaultCommand(bCommand);
hlAlert=new Alert("Item.HYPERLINK","You Can Call Me 800-8101234"
,null,AlertType.INFO);
bAlert=new Alert("Item.Button","The Button is Available!"
,null,AlertType.INFO);
aform.append("Any question ,please click ");
aform.append(hlstringItem);
aform.append(bstringItem);
aform.addCommand(okCommand);
aform.addCommand(exitCommand);
aform.setCommandListener(this);
}
public void startApp() {
aDisplay=Display.getDisplay(this);
aDisplay.setCurrent(aform);
}
public void pauseApp() {
}
public void destroyApp(boolean unconditional) {
}
public void commandAction(Command c ,Displayable d){
if(c==exitCommand){
destroyApp(false);
notifyDestroyed();
}
else{
}
}
public void commandAction(Command c,Item i){
if(c==hllinkCommand){
aDisplay.setCurrent(hlAlert,aform);
}
else if(c==bCommand){
aDisplay.setCurrent(bAlert,aform);
}
}
}
這個程序如果說有什麼比較新的東西的話,那就在於運用了StringItem的外觀模式:HYPERLINK和BUTTON。由此也使用了ItemCommandListener接口,實現了commandAction(Command c ,Item i)方法。這個方法的方法體的寫法和commandAction(Command c , Displayable d)很類似,這一點可以從程序中看出來。需要說明的是,commandAction(Command c , Item i)方法也可以使用Item變量i進行選擇,例如:
if (i==oneItem){
if (c==oneCommand){
……// the program
}}
else if (i==otherItem){
if (c==otherCommand){
…… //the program
}}
此外,該程序在編寫時,忘記寫aform.setCommandListener(this);語句了,致使EXIT按鈕按下後無法退出,這件事提醒我,編程序時要細心!