i18ndemo.java

针对moto sdk的经典源代码

/**
 * I18NDemo.java
 *
 * Oct. 15, 2004 
 *
 * (c) Copyright. 2004. Motorola , Inc. ALL RIGHTS RESERVED.
 *  This notice does not imply publication. 
 *
 */
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import java.io.*;

/**
 * Internationalization Demo. User can switch Language between English,
 * Simplified  Chinese, Traditional Chinese or default mode. 
 *
 * The default mode means that application get locale information from 
 * setting "Default-Language" in jar, if it is null, try to get system locale.
 *
 * @see MIDlet 
 */
public class I18NDemo extends MIDlet implements CommandListener, LocaleChangeListener {
	static Form  mainUI;
	static Display myDisplay;
	private Form  langChooser;

    private Command exit = null; 
    private Command switchLang = null;

	ResourceBundle i18nBundle ;
	static String jarLocale = null;
	private String currentLocale = null;
	static String locale = System.getProperty ("microedition.locale");

	public I18NDemo () {
		super ();
		myDisplay = Display.getDisplay(this);
		mainUI = new Form("title");
		jarLocale = getAppProperty ("Default-Language");
	}
	
	/**
	 * Valid return values:  "en", "sc" or "tc" * ,
	 * which stand for English, Simplified Chinese  and Traditional Chinese ,
	 * respectively.
	 */
	static public String getDefaultLocale () {
		
		if (jarLocale != null)
			return jarLocale;

                String locale = System.getProperty ("microedition.locale");

		if (locale.startsWith ("en"))
			return "en";
		else if (locale.startsWith("zh")) {
			if (locale.indexOf("CN") > 0)
				return  "sc";
			else
				return "tc";
		}

		return null;
	}

	/**
	 * Construct UI with specified locale
	 */
	private void constructUI (String locale) throws IOException {
		currentLocale = locale;
		for (int i = 0; i < mainUI.size(); i++) {
			mainUI.delete (i);
		}
		//mainUI.deleteAll();

		i18nBundle = ResourceBundle.getResourceBundle ("I18NDemo",locale);

                mainUI.setTitle (i18nBundle.getString("title"));
                mainUI.append (i18nBundle.getString("welcome"));

		if (exit != null)
			mainUI.removeCommand (exit);
		if (switchLang != null)
			mainUI.removeCommand (switchLang);
		exit = new Command(i18nBundle.getString("exit"), Command.EXIT, 3);
   		switchLang = new Command(i18nBundle.getString("switchlang"), Command.ITEM, 1);

        mainUI.addCommand (exit);
       	mainUI.addCommand (switchLang);
		mainUI.setCommandListener (this);
	}

	boolean initialized = false;
	/**
	 * Midlet lifecycle management 
	 */
	public void startApp () {

		if (!initialized) {
			String locale = getDefaultLocale ();
			try { 
				constructUI (locale);

				initialized = true;
			} catch (Exception e) {
		    	Alert alert = new Alert("Error",
		      	"Exception in UI:" + e.getMessage(),
			   	null, AlertType.ERROR);
				alert.setTimeout (Alert.FOREVER);
       	    	myDisplay.setCurrent(alert);
			}
		}

		myDisplay.setCurrent(mainUI);
	}

	public void pauseApp () {
	}

	public void destroyApp (boolean unconditional) {
        notifyDestroyed();
	}

	public void commandAction (Command c, Displayable d) {
        if (c == exit) {
            destroyApp(false);
        } else if (c == switchLang) {
			LanguageChooser chooser = LanguageChooser.getLanguageChooser(currentLocale);
			chooser.addLocaleChangeListener (this);
			myDisplay.setCurrent (chooser);
		}
	}

	public void localeChanged (String newLocale) {
		try { 
			constructUI (newLocale);
		} catch (IOException ioe) {
		   	Alert alert = new Alert("Error",
		     	"Exception when switch locale :" + ioe.getMessage(),
			   	null, AlertType.ERROR);
				alert.setTimeout (Alert.FOREVER);
       	    	myDisplay.setCurrent(alert);
		}
	}
}