package com.j2medev.chapter4;

import java.io.IOException;
import java.util.Vector;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

public class WeatherMIDlet extends MIDlet implements CommandListener{
    
    private Display display = null;
    private Form form = null;
    private Image logo = null;
    private TextField location = new TextField("Location","",20,TextField.ANY);
    private ChoiceGroup style = new ChoiceGroup("style",Choice.EXCLUSIVE,new String[]{"Fahrenheit","Celsius"},null);
    public static final Command okCommand = new Command("query",Command.OK,1);
    public static final Command backCommand = new Command("back",Command.BACK,2);
    public static final Command exitCommand = new Command("exit",Command.EXIT,3);
    
    public void startApp() {
        if(display == null){
            display = Display.getDisplay(this);
            try {
                logo = Image.createImage("/logo.png");
            } catch (IOException ex) {
                ex.printStackTrace();
            }
            ImageItem imglogo = new ImageItem("",logo,Item.LAYOUT_CENTER|Item.LAYOUT_NEWLINE_AFTER,"yahoo weather");
            form = new Form("Yahoo! weather");
            form.append(imglogo);
            form.append(location);
            form.append(style);
            form.addCommand(okCommand);
            form.addCommand(exitCommand);
            form.setCommandListener(this);
        }
        display.setCurrent(form);
    }

    public void pauseApp() {
    }
    
    public void destroyApp(boolean unconditional) {
    }
    
    public void setCurrent(Displayable displayable){
        display.setCurrent(displayable);
    }
    public void displayWeather(Vector forecasts,Location location){
        Form result = new Form("Yahoo! Weather");
        result.append(location.toString());
        //這里顯示兩天的天氣信息
        for(int i = 0;i<forecasts.size();i++){
            result.append(((Forecast)forecasts.elementAt(i)).toString());
        }
        result.addCommand(backCommand);
        result.setCommandListener(this);
        display.setCurrent(result);
    }
    public void commandAction(Command cmd,Displayable displayable){
        if(cmd == okCommand){
            //位置和單位
            String p = location.getString();
            int index = style.getSelectedIndex();
            String s = index > 0?"c":"f";
            String param = "p="+p+"&u="+s;
            //查詢天氣預報
            new Thread(new WeatherReader(this,param)).start();
        }else if(cmd == backCommand){
            display.setCurrent(form);
        }else if(cmd == exitCommand){
            destroyApp(false);
            notifyDestroyed();
        }
    }
}