實驗結果:
打開應用首頁面:輸入濱州
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!