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Android實驗九之天氣預報

實驗結果:

打開應用首頁面:輸入濱州

Android實驗九之天氣預報
Android實驗九之天氣預報

代碼:

WeatherAtivity.java

package com.example.weather;

import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;

import model.Weather;
import Util.HttpCallbackListener;
import Util.HttpUtil;
import adapter.WeatherAdapter;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.LayoutAnimationController;
import android.view.animation.ScaleAnimation;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.ListView;
import android.widget.Toast;

import com.google.gson.JsonArray;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;


public class WeatherActivity extends Activity{

	private EditText etCity;
	private ImageButton btnQuery;
	private ListView lvFutureWeather;
	public static final int SHOW_PESPONSE = 1;
	private List<Weather> data;
	
	
		private void parseWithJSON(String response){
			data = new ArrayList<Weather>();
			JsonParser parser = new JsonParser();
			JsonObject obj = (JsonObject) parser.parse(response);
			//傳回狀态碼
			String resultcode = obj.get("resultcode").getAsString();
			//如果狀态碼是200說明傳回資料成功
			if(resultcode != null && resultcode.equals("200")){
				JsonObject resultObj = obj.get("result").getAsJsonObject();
				JsonArray futureWeatherArray = resultObj.get("future").getAsJsonArray();
				for(int i=0;i<futureWeatherArray.size();i++){
					Weather weather = new Weather();
					JsonObject weatherObject = futureWeatherArray.get(i).getAsJsonObject();
					weather.setDayOfWeek(weatherObject.get("week").getAsString());
					weather.setDate(weatherObject.get("date").getAsString());
					weather.setTemperature(weatherObject.get("temperature").getAsString());
					weather.setWeather(weatherObject.get("weather").getAsString());
					data.add(weather);
				}
			}
		}
		
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_weather);
		setListeners();
		initView();
		
	}
	private void setListeners() {
		etCity = (EditText) findViewById(R.id.etCity);
		btnQuery = (ImageButton) findViewById(R.id.btnQuery);
		lvFutureWeather = (ListView) findViewById(R.id.lvFutureWeather);
		
	}
	private void initView() {
		btnQuery.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				String city = etCity.getText().toString();
				try{
					city = URLEncoder.encode("濱州", "utf-8");//至關重要的一句
				}catch(UnsupportedEncodingException e){
					e.printStackTrace();
				}
				System.out.println("cityName=" + city);
				System.out.println("lvFutureWeather="+lvFutureWeather);
				Toast.makeText(WeatherActivity.this, "success", Toast.LENGTH_LONG).show();
				String weatherUrl = "http://v.juhe.cn/weather/index?format=2&cityname="+city+"&key=2e0565f85c267f344e16bd5b89c55444";
				HttpUtil.sendHttpRequest(weatherUrl, new HttpCallbackListener() {
					
					@Override
					public void onFinish(String response) {
						Message message = new Message();
						message.what = SHOW_PESPONSE;
						//将伺服器傳回的結果存放到Message中
						message.obj = response.toString();
						handler.sendMessage(message);
						
					}
					
					@Override
					public void onError(Exception e) {
						System.out.println("通路失敗");
						
					}
				});
				
			}
		});
		
	}
	
private Handler handler = new Handler(){
		
		public void handleMessage(android.os.Message msg) {
			switch(msg.what){
			case SHOW_PESPONSE:
				String response = (String) msg.obj;
				//Toast.makeText(WeatherActivity.this, response, Toast.LENGTH_LONG).show();
				System.out.println("response="+response);
				if(response != null){
					parseWithJSON(response);
					WeatherAdapter weatherAdapter = new WeatherAdapter(
							WeatherActivity.this,
							R.layout.activity_weather_listitem,data);
							lvFutureWeather.setAdapter(weatherAdapter);
							ScaleAnimation scaleAnimation = new ScaleAnimation(0,1,0,1);
							scaleAnimation.setDuration(1000);
							LayoutAnimationController animationController = 
									new LayoutAnimationController(scaleAnimation,0.6f);
							lvFutureWeather.setLayoutAnimation(animationController);
									
				}
			default:
				break;
			}
			
		}
	};	
	
}
           

activity_weather.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" 
    android:background="@drawable/activity_weather_bg"
    >
    <LinearLayout 
        android:id="@+id/linearlayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        >
        <EditText 
            android:id="@+id/etCity"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginLeft="10dp"
            android:layout_marginTop="20dp"
            android:layout_weight="1"
            android:background="@android:drawable/edit_text"
            android:drawableLeft="@drawable/icons_weather_city"
            android:drawablePadding="5dp"
            android:ems="10"
            android:hint="@string/etCity"
           >
           <requestFocus/>
           
        </EditText>
        
        <ImageButton 
            android:id="@+id/btnQuery"
            android:layout_width="50dp"
            android:layout_height="50dp"
            android:layout_marginTop="20dp"
            android:background="@null"
            android:src="@drawable/icons_weather_query"/>
    </LinearLayout>

    <ListView
        android:id="@+id/lvFutureWeather"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:dividerHeight="10dp"
        android:layoutAnimation="@anim/weather_list_layout_animation" >
    </ListView>

</RelativeLayout>
           

activity_weather_listitem.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="10dp"
    android:layout_margin="10dp"
    android:background="@drawable/list_item_shape" >
    
    <TextView 
        android:id="@+id/tvDayofWeek"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:text="星期日"
        />
    <TextView 
        android:id="@+id/tvDate"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/tvDayofWeek"
        android:layout_alignBottom="@+id/tvDayofWeek"
        android:layout_alignParentRight="true"
        android:text="20160207"/>
    <TextView 
        android:id="@+id/tvTemperature"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/tvDayofWeek"
        android:layout_below="@+id/tvDayofWeek"
        android:layout_marginTop="15dp"
        android:text="temperature"/>
    <TextView 
        android:id="@+id/tvWeather"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/tvTemperature"
        android:layout_below="@+id/tvTemperature"
        android:layout_marginTop="15dp"
        android:text="weather"/>

</RelativeLayout>
           

Weather.java

package model;

import android.R.string;

public class Weather {

	private String dayOfWeek;
	private String date;
	private String temperature;
	private String weather;
	public Weather(){
		
	}
	public Weather(String dayOfWeek,String date,String temperature,
			String weather){
		super();
		this.dayOfWeek = dayOfWeek;
		this.date = date;
		this.temperature = temperature;
		this.weather = weather;
	}
	public String getDayOfWeek() {
		return dayOfWeek;
	}
	public void setDayOfWeek(String dayOfWeek) {
		this.dayOfWeek = dayOfWeek;
	}
	public String getDate() {
		return date;
	}
	public void setDate(String date) {
		this.date = date;
	}
	public String getTemperature() {
		return temperature;
	}
	public void setTemperature(String temperature) {
		this.temperature = temperature;
	}
	public String getWeather() {
		return weather;
	}
	public void setWeather(String weather) {
		this.weather = weather;
	}
	
	@Override
	public String toString() {
		// TODO Auto-generated method stub
		return "Weather[dayOfWeek="+dayOfWeek+",date="+date+",temperature="
				+temperature+",weather="+weather+"]";
	}
}
           

WeatherAdapter.java

package adapter;

import java.util.List;

import com.example.weather.R;

import model.Weather;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;

public class WeatherAdapter extends ArrayAdapter<Weather>{
	private int resourceId;	
	
	public WeatherAdapter(Context context, int textViewResourceId, List<Weather> objects) {
		super(context, textViewResourceId, objects);
		resourceId = textViewResourceId;
	}

	public View getView(int position,View convertView,ViewGroup viewgroup){
		Weather weather = getItem(position);
		ViewHolder viewHolder = null;
		if (convertView == null){
			viewHolder = new ViewHolder();
			convertView = LayoutInflater.from(getContext()).inflate(resourceId, null);
			viewHolder.tvDayOdWeek =  (TextView) convertView.findViewById(R.id.tvDayofWeek);
			viewHolder.tvDate = (TextView) convertView.findViewById(R.id.tvDate);			
			viewHolder.tvTemperature = (TextView) convertView.findViewById(R.id.tvTemperature);
			viewHolder.tvWeather = (TextView) convertView.findViewById(R.id.tvWeather);
			convertView.setTag(viewHolder);
			
			
		}else{
			viewHolder= (ViewHolder) convertView.getTag();
		}
		viewHolder.tvDayOdWeek.setText(weather.getDayOfWeek());
		viewHolder.tvDate.setText(weather.getDate());
		viewHolder.tvTemperature.setText(weather.getTemperature());
		viewHolder.tvWeather.setText(weather.getWeather());
		return convertView;
	}

	private class ViewHolder{
		TextView tvDayOdWeek;
		TextView tvDate;
		TextView tvTemperature;
		TextView tvWeather;
	}
	

}
           

HttpCallbackListener.java

package Util;

public interface HttpCallbackListener {

	void onFinish(String response);
	void onError(Exception e);
}
           

HttpUtil.java

package Util;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

import android.R.string;

public class HttpUtil {

	public static void sendHttpRequest(final String address,final HttpCallbackListener listener){
		new Thread(new Runnable() {
			
			@Override
			public void run() {
				HttpURLConnection connection = null;
				try {
					URL url = new URL(address);
					connection = (HttpURLConnection) url.openConnection();
					connection.setRequestMethod("GET");
					connection.setReadTimeout(8000);
					connection.setConnectTimeout(8000);
					connection.setDoInput(true);
					connection.setDoOutput(true);
					InputStream in = connection.getInputStream();
					BufferedReader reader = 
							new BufferedReader(new InputStreamReader(in));
					StringBuilder response = new StringBuilder();
					String line;
					while ((line = reader.readLine()) != null) {
						response.append(line);
					}
					if(listener != null){
						//回調onfinish方法
						listener.onFinish(response.toString());
						
					}
				} catch (IOException e) {
					if(listener != null){
						listener.onError(e);
					}
					
				}finally {
					connection.disconnect();
				}
				
				
			}
		}).start();
	}
}
           

總結:

需要注意的兩點:1、該應用中用到了JSON,是以應向libs中導入google的json-2.2.4.jar,才可以使用JSON解析器,對傳回資料進行處理。2、該應用要從聚合網獲得天氣接口,要使用新申請的KEY。

案例3word的出現了一處錯誤,在WeatherActivity.java的onCreat方法中,應先定義各值調用setListener();然後再初始化UI調用initView();順序颠倒則會出現空指針異常錯誤!