Android实现天气查询

这里实现 省份–城市–天气 的联动。即先选择省份，再选择城市，最后展示天气信息。
思路：通过访问：http://www.webxml.com.cn/webservices/weatherwebservice.asmx，通过给定的方式获得所需要的数据，在方法中解析xml成list，然后展示即可。

1：布局与权限：

<uses-permission android:name="android.permission.INTERNET" />

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"    android:layout_height="match_parent"     tools:context="com.inext.test.webview.WeatherActivity">    <Spinner        android:id="@+id/pro"        android:layout_width="match_parent"        android:layout_height="wrap_content"></Spinner>    <Spinner        android:id="@+id/city"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_below="@+id/pro"        android:layout_alignParentStart="true"></Spinner>    <ScrollView        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_below="@+id/city"        android:layout_alignParentStart="true">        <TextView            android:id="@+id/show"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:layout_below="@+id/city"            android:layout_alignParentStart="true" />    </ScrollView></RelativeLayout>

2：xml解析类，用于解析从站点返回的xml流，返回list：

/** * Created by Administrator on 2016/5/10. * 解析xml工具类 */public class XMLUtil {    private InputStream inputStream;    public XMLUtil(InputStream inputStream){        this.inputStream = inputStream;    }    //解析流成list    public List getAllElement() throws XmlPullParserException, IOException {        List list = null;        XmlPullParserFactory factory = XmlPullParserFactory.newInstance();        XmlPullParser xpp = factory.newPullParser();        xpp.setInput(inputStream,"utf-8");        //事件        int eventType = xpp.getEventType();        String elementName = "";        //当事件不结束时        while (eventType!=XmlPullParser.END_DOCUMENT){            switch (eventType){                //开始                case XmlPullParser.START_DOCUMENT:                    list = new ArrayList();                    break;                //开始一个标签                case XmlPullParser.START_TAG:                    //获得标签名称                    elementName = xpp.getName();                    break;                //获得标签内容                case XmlPullParser.TEXT:                    if (elementName.equals("string")){                        list.add(xpp.getText());                    }                    break;                //标签结束                case XmlPullParser.END_TAG:                    break;            }            eventType = xpp.next();        }        return list;    }}

3：应用类：

public class WeatherActivity extends AppCompatActivity {    private List list_city,list_pro,list_data;    private Spinner pro,city;    private TextView show;    private  Context context = getBaseContext();    private String cityName,proName,url_city,url_city_data;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_weather);        pro = (Spinner)findViewById(R.id.pro);        city = (Spinner)findViewById(R.id.city);        show = (TextView)findViewById(R.id.show);        //获取省份的地址        String url_pro = "http://www.webxml.com.cn/webservices/weatherwebservice.asmx/getSupportProvince";        //执行获取省份的异步操作        new MyAsync().execute(url_pro);    }    //获取省份。   城市和天气的获取与解析都是一样的思路    public class MyAsync extends AsyncTask<String,Void,List>{        @Override        protected List doInBackground(String... params) {            //调用getXml（）方法，（该方法在本类底部位置）            list_pro = getXml(params[0]);            return list_pro;        }        @Override        protected void onPostExecute(List list) {            super.onPostExecute(list);            if (list==null || list.size()==0){                return;            }            Toast.makeText(getBaseContext(),""+list.size(),Toast.LENGTH_SHORT).show();            ArrayAdapter arrayAdapter = new ArrayAdapter(getBaseContext(),android.R.layout.simple_dropdown_item_1line,list_pro);            pro.setAdapter(arrayAdapter);            pro.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {                @Override                public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {                    proName = pro.getSelectedItem().toString().trim();                    //Toast.makeText(getBaseContext(),proName,Toast.LENGTH_SHORT).show();                    url_city = "http://www.webxml.com.cn/webservices/weatherwebservice.asmx/getSupportCity?byProvinceName="+proName;                    new MyAsyncCity().execute(url_city);                }                @Override                public void onNothingSelected(AdapterView<?> parent) {                }            });        }    }    //获取城市    public class MyAsyncCity extends AsyncTask<String,Void,List>{        @Override        protected List doInBackground(String... params) {            list_city = getXml(params[0]);            return list_city;        }        @Override        protected void onPostExecute(List list) {            super.onPostExecute(list);            if (list==null || list.size()==0){                return;            }            //Toast.makeText(getBaseContext(),""+list.size(),Toast.LENGTH_SHORT).show();            ArrayAdapter arrayAdapter = new ArrayAdapter(getBaseContext(),android.R.layout.simple_dropdown_item_1line,list_city);            city.setAdapter(arrayAdapter);            arrayAdapter.notifyDataSetChanged();            city.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {                @Override                public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {                    cityName = city.getSelectedItem().toString().trim();                    cityName = cityName.split(" ")[0];                    if (!city.equals("")){                        url_city_data = "http://www.webxml.com.cn/webservices/weatherwebservice.asmx/getWeatherbyCityName?theCityName="+cityName;                        Toast.makeText(getBaseContext(),cityName,Toast.LENGTH_SHORT).show();                        new MyWeather().execute(url_city_data);                    }                }                @Override                public void onNothingSelected(AdapterView<?> parent) {                }            });        }    }    public class MyWeather extends AsyncTask<String,Void,List>{        @Override        protected List doInBackground(String... params) {            list_data = getXml(params[0]);            return list_data;        }        @Override        protected void onPostExecute(List list) {            super.onPostExecute(list);            StringBuilder sb = new StringBuilder();            if (list_data.size()!=0 && list_data!=null){                for (int i=0;i<list_data.size();i++){                    String str = list.get(i).toString();                    sb.append(str+"\n");                }                show.setText(sb.toString());            }        }    }    //getXml方法，解析获得流，并调用XMLUtil类解析流    public List getXml(String urlString){        List list = null;        InputStream is = null;        HttpURLConnection httpURLConnection = null;        try {            URL url = new URL(urlString);            httpURLConnection = (HttpURLConnection) url.openConnection();            httpURLConnection.setConnectTimeout(5000);            httpURLConnection.setReadTimeout(5000);            if (httpURLConnection.getResponseCode()==200){                //获取返回的数据流                is = httpURLConnection.getInputStream();                //传入Xml解析工具类进行解析                XMLUtil xmlUtil = new XMLUtil(is);                try {                    list = xmlUtil.getAllElement();                } catch (XmlPullParserException e) {                    e.printStackTrace();                }            }else {                Toast.makeText(context,"网络异常",Toast.LENGTH_SHORT).show();                return null;            }        } catch (MalformedURLException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }finally {            try {                if (is!=null){                    is.close();                }                if (httpURLConnection!=null){                    httpURLConnection.disconnect();                }            } catch (IOException e) {                e.printStackTrace();            }        }        return list;    }}