简单的天气预报Demo

一、需求

选择城市获得相应城市最近几天的天气预报

数据源：

1、全国城市列表xml -----http://yunpan.cn/cmMA5DrFeM4m6 （提取码：ccb1）

2、天气json数据源 http://weather.xcyh.org/101210401/json/6   101210401部分为城市的编号

二、设计思路

三个下拉列表 分别显示省、市、县的名字，一个按钮 为查询   一个ListView显示最近该城市几天的天气预报

xml解析获取城市名称集合，json解析获取天气

1、点击省列表选择省，对应市列表和县列表名跟随变化

2、点击市列表选择市，对应县列表名跟随变化

3、点击查询按钮，获得当前县名的天气预报数据，显示在ListView控件中 （每一个县都有一个id，根据该id获得天气数据的网址，获得json解析并显示）

效果图：

三、Demo代码

1、布局文件

 1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:orientation="vertical"
 6     >
 7
 8     <LinearLayout
 9         android:layout_width="match_parent"
10         android:layout_height="wrap_content"
11         android:orientation="horizontal"
12         >
13     <Spinner
14         android:layout_width="0dp"
15         android:layout_weight="1"
16         android:layout_height="wrap_content"
17         android:id="@+id/province"
18         />
19     <Spinner
20         android:layout_width="0dp"
21         android:layout_weight="1"
22         android:layout_height="wrap_content"
23         android:id="@+id/city"
24         />
25     <Spinner
26         android:layout_width="0dp"
27         android:layout_weight="1"
28         android:layout_height="wrap_content"
29         android:id="@+id/district"
30         />
31     <Button
32         android:layout_width="wrap_content"
33         android:layout_height="wrap_content"
34         android:id="@+id/submit"
35         android:text="@string/select"
36         />
37     </LinearLayout>
38
39     <LinearLayout
40         android:layout_width="match_parent"
41         android:layout_height="wrap_content"
42         android:orientation="vertical"
43         >
44         <ListView
45             android:layout_width="match_parent"
46             android:layout_height="wrap_content"
47             android:id="@+id/id_listview"
48             ></ListView>
49
50     </LinearLayout>
51 </LinearLayout>

activity_main

2、实体类（省类，市类，县类）

 1 package entity;
 2
 3 import java.util.List;
 4
 5 public class Province {
 6     //根据城市xml文件可知， 省有id ，省名 ，该省所有的市集合  三个属性
 7     private String id;
 8     private String name;
 9     private List<City> citys;
10     public Province() {
11         super();
12         // TODO Auto-generated constructor stub
13     }
14     public Province(String id, String name, List<City> citys) {
15         super();
16         this.id = id;
17         this.name = name;
18         this.citys = citys;
19     }
20     public String getId() {
21         return id;
22     }
23     public void setId(String id) {
24         this.id = id;
25     }
26     public String getName() {
27         return name;
28     }
29     public void setName(String name) {
30         this.name = name;
31     }
32     public List<City> getCitys() {
33         return citys;
34     }
35     public void setCitys(List<City> citys) {
36         this.citys = citys;
37     }
38     @Override
39     public String toString() {
40         return name;
41     }
42
43
44
45 }

Province.class

 1 package entity;
 2
 3 import java.util.List;
 4
 5 public class City {
 6     //根据城市xml文件可知，市 有id,市名，该市所有的县 的集合 三个属性
 7     private String id;
 8     private String name;
 9     private List<District> districts;
10     public City() {
11         super();
12         // TODO Auto-generated constructor stub
13     }
14     public City(String id, String name, List<District> districts) {
15         super();
16         this.id = id;
17         this.name = name;
18         this.districts = districts;
19     }
20     public String getId() {
21         return id;
22     }
23     public void setId(String id) {
24         this.id = id;
25     }
26     public String getName() {
27         return name;
28     }
29     public void setName(String name) {
30         this.name = name;
31     }
32     public List<District> getDistricts() {
33         return districts;
34     }
35     public void setDistricts(List<District> districts) {
36         this.districts = districts;
37     }
38     @Override
39     public String toString() {
40         return name;
41     }
42
43
44
45 }

City.class

 1 package entity;
 2
 3 import java.util.Arrays;
 4
 5 public class District {
 6     //根据城市XML文件可知 县有 id,县名 两个属性
 7     private String id;
 8     private String name;
 9
10     //根据天气数据源和需求可知，县还具有 日期，天气，温度，风向 四个属性  ，每一个属性包含该县最近几天的相应情况
11     private String date[] = new String[6];
12     private String weather[] = new String[6];
13     private String temperature[] = new String[6];
14     private String winddirect[] = new String[6];
15     public District() {
16         super();
17         // TODO Auto-generated constructor stub
18     }
19     public District(String id, String name, String[] date, String[] weather,
20             String[] temperature, String[] winddirect) {
21         super();
22         this.id = id;
23         this.name = name;
24         this.date = date;
25         this.weather = weather;
26         this.temperature = temperature;
27         this.winddirect = winddirect;
28     }
29     public String getId() {
30         return id;
31     }
32     public void setId(String id) {
33         this.id = id;
34     }
35     public String getName() {
36         return name;
37     }
38     public void setName(String name) {
39         this.name = name;
40     }
41     public String[] getDate() {
42         return date;
43     }
44     public void setDate(String[] date) {
45         this.date = date;
46     }
47     public String[] getWeather() {
48         return weather;
49     }
50     public void setWeather(String[] weather) {
51         this.weather = weather;
52     }
53     public String[] getTemperature() {
54         return temperature;
55     }
56     public void setTemperature(String[] temperature) {
57         this.temperature = temperature;
58     }
59     public String[] getWinddirect() {
60         return winddirect;
61     }
62     public void setWinddirect(String[] winddirect) {
63         this.winddirect = winddirect;
64     }
65     @Override
66     public String toString() {
67         return name;
68     }
69
70
71
72
73 }

District.class

3、解析城市列表xml文件的自定义工具类

  1 package tools;
  2
  3 import java.io.IOException;
  4 import java.util.ArrayList;
  5 import java.util.List;
  6
  7 import org.xmlpull.v1.XmlPullParser;
  8 import org.xmlpull.v1.XmlPullParserException;
  9 import org.xmlpull.v1.XmlPullParserFactory;
 10
 11 import com.example.weather_day.R;
 12
 13 import android.content.Context;
 14 import android.content.res.Resources;
 15 import android.util.Log;
 16 import entity.City;
 17 import entity.District;
 18 import entity.Province;
 19
 20 public class ParserTool {
 21     //pull解析
 22     private Context context;
 23     public ParserTool(Context context)
 24     {
 25         this.context = context;
 26     }
 27     public static List PullParser(Context context) throws XmlPullParserException, IOException
 28     {
 29         XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
 30         XmlPullParser parser = factory.newPullParser();
 31         List<Province> provinces = null;
 32         List<City> citys = null;
 33         List<District> districts = null;
 34         Province province = null;
 35         City city = null;
 36         District district  =null;
 37
 38         //城市列表xml文件在res-raw文件夹下
 39         Resources resources = context.getResources();
 40         parser.setInput(resources.openRawResource(R.raw.citys_weather),"utf-8");
 41
 42         int event = parser.getEventType();
 43
 44         while(event!=XmlPullParser.END_DOCUMENT)
 45         {
 46             switch (event) {
 47             case XmlPullParser.START_DOCUMENT:
 48                 provinces = new ArrayList<Province>();
 49
 50                 break;
 51
 52             case XmlPullParser.START_TAG:
 53                 if("p".equals(parser.getName()))
 54                 {
 55                     province = new Province();
 56                     citys = new ArrayList<City>();
 57                     int count = parser.getAttributeCount();
 58                     for(int i=0;i<count;i++)
 59                     {
 60                         String key = parser.getAttributeName(i);
 61                         String value = parser.getAttributeValue(i);
 62                         if("p_id".equals(key))
 63                         {
 64                             province.setId(value);
 65                         }
 66                     }
 67 //                    provinces.add(province);
 68                 }
 69                 else if("pn".equals(parser.getName()))
 70                 {
 71                     province.setName(parser.nextText());
 72                 }
 73                 else if("c".equals(parser.getName()))
 74                 {
 75                     city = new City();
 76                     districts = new ArrayList<District>();
 77                     int count = parser.getAttributeCount();
 78                     for(int i=0;i<count;i++)
 79                     {
 80
 81                         String key = parser.getAttributeName(i);
 82                         String value = parser.getAttributeValue(i);
 83                         if("c_id".equals(key))
 84                         {
 85                             city.setId(value);
 86                         }
 87                     }
 88 //                    citys.add(city);
 89                 }
 90                 else if("cn".equals(parser.getName()))
 91                 {
 92                     city.setName(parser.nextText());
 93                 }
 94                 else if("d".equals(parser.getName()))
 95                 {
 96                     district = new District();
 97                     int count = parser.getAttributeCount();
 98                     for(int i=0;i<count;i++)
 99                     {
100                         String key = parser.getAttributeName(i);
101                         String value = parser.getAttributeValue(i);
102                         if("d_id".equals(key))
103                         {
104                             district.setId(value);
105                         }
106                     }
107                     district.setName(parser.nextText());
108                     districts.add(district);
109                 }
110                 break;
111             case XmlPullParser.END_TAG:
112                 if("p".equals(parser.getName()))
113                 {
114                     province.setCitys(citys);
115                     provinces.add(province);
116                 }
117                 else if("c".equals(parser.getName()))
118                 {
119                     city.setDistricts(districts);
120                     citys.add(city);
121                 }
122
123
124                 break;
125             default:
126                 break;
127             }
128             event = parser.next();
129         }
130         //返回省的列表
131         return provinces;
132     }
133 }

ParserTool.class

4、解析网络天气数据源的自定义工具类

（1）、获取json字符串

 1 package tools;
 2
 3 import java.io.ByteArrayOutputStream;
 4 import java.io.IOException;
 5 import java.io.InputStream;
 6 import java.io.UnsupportedEncodingException;
 7 import java.net.HttpURLConnection;
 8 import java.net.URL;
 9
10 public class HttpUtil {
11     public static String getJsonString(String path) throws IOException{
12         //参数为解析数据源的地址
13         URL url = new URL(path);
14         HttpURLConnection conn = (HttpURLConnection) url.openConnection();
15         //GET连接
16         conn.setRequestMethod("GET");
17         conn.setConnectTimeout(5000);
18         conn.setDoInput(true);
19
20         if(conn.getResponseCode()==200)
21         {
22             InputStream in = conn.getInputStream();
23             return getJson(in);
24         }
25         return null;
26     }
27
28     public static String getJson(InputStream in ) throws IOException
29     {
30         //将解析后的数据写入内存
31         ByteArrayOutputStream out = new ByteArrayOutputStream();
32         int len = 0;
33         byte b[] = new byte[1024];
34         while((len=in.read(b))!=-1)
35         {
36             //不要写成out.write(b);
37             out.write(b,0,len);
38         }
39         //不要忘记第二个参数，避免乱码
40         return new String(out.toByteArray(),"utf-8");
41
42     }
43 }

HttpUtil.class

（2）、解析json字符串

 1 package tools;
 2
 3 import java.util.ArrayList;
 4 import java.util.List;
 5
 6 import org.json.JSONArray;
 7 import org.json.JSONException;
 8 import org.json.JSONObject;
 9
10 import android.util.Log;
11
12 import entity.District;
13
14 public class ParserJson {
15     public static District JsonString(String json) throws JSONException
16     {
17         JSONObject obj = new JSONObject(json);
18         JSONArray arr = obj.getJSONArray("data");
19         District district2 = new District();
20         String date[] = new String[6];
21         String weather[] = new String[6];
22         String temperature[] = new String[6];
23         String winddirect[] = new String[6];
24         /*
25          *思路为实体类 -县    具有日期date，天气weather,温度temperature,风向winddirect 四个属性
26          *每一个属性为一个字符串数据，存放该县近几天的对应数据
27          */
28         for(int i=0;i<arr.length();i++)
29         {
30             JSONObject data = arr.getJSONObject(i);
31             date[i] = data.getString("date");
32             weather[i] = data.getString("weather");
33             temperature[i] = data.getString("temperature");
34             winddirect[i] = data.getString("winddirect");
35         }
36         district2.setDate(date);
37         district2.setWeather(weather);
38         district2.setTemperature(temperature);
39         district2.setWinddirect(winddirect);
40         //返回县 的对象
41         return district2;
42     }
43 }

ParserJson.class

5、异步任务

网络下载解析等耗时操作一定要放入异步任务中实现功能！

 1 package Asynch;
 2
 3 import java.io.IOException;
 4 import java.util.List;
 5
 6 import org.json.JSONException;
 7
 8 import tools.HttpUtil;
 9 import tools.ParserJson;
10 import entity.District;
11
12 import android.content.Context;
13 import android.os.AsyncTask;
14 import android.util.Log;
15 import android.widget.ArrayAdapter;
16 import android.widget.ListView;
17
18 public class AsynchTaskWeather extends AsyncTask<String, Void, District>{
19
20     private Context context;
21     private ListView listview;
22     List<District> list_district;
23     private District district;
24     public AsynchTaskWeather(Context context,ListView listview)
25     {
26         this.context =context;
27         this.listview = listview;
28     }
29     @Override
30     protected District doInBackground(String... params) {
31         // TODO Auto-generated method stub
32         //实现任务功能的方法
33         if(params[0]!=null)
34         {
35             String json;
36             try {
37                 //获得json字符串
38                 json = HttpUtil.getJsonString(params[0]);
39                 //解析Json字符串返回该对象，该对象为一个县 包含该县近几天的天气情况
40                 district = ParserJson.JsonString(json);
41
42             } catch (IOException e) {
43                 // TODO Auto-generated catch block
44                 e.printStackTrace();
45             } catch (JSONException e) {
46                 // TODO Auto-generated catch block
47                 e.printStackTrace();
48             }
49         }
50         return district;
51     }
52
53     @Override
54     protected void onPostExecute(District result) {
55         // TODO Auto-generated method stub
56 //        Log.i("-------------------", result.toString());
57         super.onPostExecute(result);
58         String date[] = result.getDate();
59         String weather[] = result.getWeather();
60         String temperature[] = result.getTemperature();
61         String winddirect[] = result.getWinddirect();
62         int n = date.length;
63         String arr[] = new String[6];
64         //将返回对象的属性（天气温度风向等）放入字符串数组中作为listview适配器的数据源
65         for(int i=0;i<date.length;i++)
66         {
67             arr[i]=("日期:"+date[i]+"|天气:"+weather[i]+"|温度:"+temperature[i]+"|风向:"+winddirect[i]);
68         }
69         ArrayAdapter<String> ada = new ArrayAdapter<String>(context, android.R.layout.simple_list_item_1,arr);
70         listview.setAdapter(ada);
71     }
72 }

AsynchTaskWeather.class

6、主Activity

  1 package com.example.weather_day;
  2
  3 import java.io.IOException;
  4 import java.nio.channels.AsynchronousCloseException;
  5 import java.util.List;
  6
  7 import org.json.JSONException;
  8 import org.xmlpull.v1.XmlPullParserException;
  9
 10 import tools.HttpUtil;
 11 import tools.ParserJson;
 12 import tools.ParserTool;
 13 import Asynch.AsynchTaskWeather;
 14 import android.app.Activity;
 15 import android.os.Bundle;
 16 import android.view.View;
 17 import android.view.View.OnClickListener;
 18 import android.widget.AdapterView;
 19 import android.widget.AdapterView.OnItemSelectedListener;
 20 import android.widget.ArrayAdapter;
 21 import android.widget.Button;
 22 import android.widget.ListView;
 23 import android.widget.Spinner;
 24 import entity.City;
 25 import entity.District;
 26 import entity.Province;
 27
 28 public class MainActivity extends Activity {
 29
 30     private Spinner spinner_province;
 31     private Spinner spinner_city;
 32     private Spinner spinner_district;
 33     private ListView listview;
 34
 35     private Button btn_submit;
 36
 37     int province = 0;
 38     int city = 0;
 39     int district = 0;
 40
 41     List<Province> list;
 42     @Override
 43     protected void onCreate(Bundle savedInstanceState) {
 44         super.onCreate(savedInstanceState);
 45         setContentView(R.layout.activity_main);
 46
 47         initView();
 48
 49
 50
 51         try {
 52             list = ParserTool.PullParser(this);
 53
 54             ArrayAdapter<Province> ada_province = new ArrayAdapter<Province>(this, android.R.layout.simple_list_item_1,list);
 55             spinner_province.setAdapter(ada_province);
 56
 57             ArrayAdapter<City> ada_city = new ArrayAdapter<City>(this, android.R.layout.simple_list_item_1,list.get(0).getCitys());
 58             spinner_city.setAdapter(ada_city);
 59
 60             ArrayAdapter<District> ada_districy = new ArrayAdapter<District>(this, android.R.layout.simple_list_item_1,list.get(0).getCitys().get(0).getDistricts());
 61             spinner_district.setAdapter(ada_districy);
 62
 63             spinner_province.setOnItemSelectedListener(new OnItemSelectedListener() {
 64
 65                 @Override
 66                 public void onItemSelected(AdapterView<?> arg0, View arg1,
 67                         int arg2, long arg3) {
 68                     // TODO Auto-generated method stub
 69                     province = arg2;
 70                     ArrayAdapter<City> ada_city = new ArrayAdapter<City>(MainActivity.this, android.R.layout.simple_list_item_1,list.get(province).getCitys());
 71                     spinner_city.setAdapter(ada_city);
 72
 73                 }
 74
 75                 @Override
 76                 public void onNothingSelected(AdapterView<?> arg0) {
 77                     // TODO Auto-generated method stub
 78
 79                 }
 80             });
 81
 82             spinner_city.setOnItemSelectedListener(new OnItemSelectedListener() {
 83
 84                 @Override
 85                 public void onItemSelected(AdapterView<?> arg0, View arg1,
 86                         int arg2, long arg3) {
 87                     // TODO Auto-generated method stub
 88                     city = arg2;
 89                     ArrayAdapter<District> ada_district = new ArrayAdapter<District>(MainActivity.this, android.R.layout.simple_list_item_1,list.get(province).getCitys().get(city).getDistricts());
 90                     spinner_district.setAdapter(ada_district);
 91                 }
 92
 93                 @Override
 94                 public void onNothingSelected(AdapterView<?> arg0) {
 95                     // TODO Auto-generated method stub
 96
 97                 }
 98             });
 99
100             spinner_district.setOnItemSelectedListener(new OnItemSelectedListener() {
101
102                 @Override
103                 public void onItemSelected(AdapterView<?> arg0, View arg1,
104                         int arg2, long arg3) {
105                     // TODO Auto-generated method stub
106                     district = arg2;
107                 }
108
109                 @Override
110                 public void onNothingSelected(AdapterView<?> arg0) {
111                     // TODO Auto-generated method stub
112
113                 }
114             });
115
116             btn_submit.setOnClickListener(new OnClickListener() {
117
118                 @Override
119                 public void onClick(View v) {
120                     // TODO Auto-generated method stub
121                     String id = list.get(province).getCitys().get(city).getDistricts().get(district).getId();
122                     String path = "http://weather.xcyh.org/"+id+"/json/6";
123                     new AsynchTaskWeather(MainActivity.this, listview).execute(path);
124
125                 }
126             });
127
128         } catch (XmlPullParserException e) {
129             // TODO Auto-generated catch block
130             e.printStackTrace();
131         } catch (IOException e) {
132             // TODO Auto-generated catch block
133             e.printStackTrace();
134         }
135
136
137     }
138     private void initView() {
139         spinner_province = (Spinner) findViewById(R.id.province);
140         spinner_city = (Spinner) findViewById(R.id.city);
141         spinner_district = (Spinner) findViewById(R.id.district);
142         btn_submit = (Button) findViewById(R.id.submit);
143         listview = (ListView) findViewById(R.id.id_listview);
144     }
145
146
147
148 }