navigator.java

j2me实例代码

package serverlet;

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import java.util.*;

public class Navigator {
	final public static int MAIN_SCREEN=1;
	final public static int USERDATA_SCREEN=2;
	final public static int UPDATEUSERDATA_SCREEN=3;
	
	public static MIDlet midlet;
	public static Display display;
	public static int current;
	
	public static void show(Object obj){
		switch(current){
		case MAIN_SCREEN:
			display.setCurrent(MainScreen.getInstance());
			break;
		case USERDATA_SCREEN:
			display.setCurrent(new UserDataScreen((Vector)obj));
			break;
		case UPDATEUSERDATA_SCREEN:
			display.setCurrent(UpdateUserDataScreen.getInstance());
			break;
			
		}
	}
	
	public static void flow(String cmd){
		switch(current){
		case MAIN_SCREEN:
			if(cmd.equals("exit")){
				midlet.notifyDestroyed();
			}else if(cmd.equals("add")){
				current=UPDATEUSERDATA_SCREEN;
				show(null);
			}
			break;
		case USERDATA_SCREEN:
			if(cmd.equals("exit")){
				midlet.notifyDestroyed();
			}else if(cmd.equals("back")){
				current=MAIN_SCREEN;
				show(null);
			}
			break;
		case UPDATEUSERDATA_SCREEN:
			if(cmd.equals("back")){
				current=MAIN_SCREEN;
				show(null);
			}
			break;
		}
	}
}