1，使用Googel API
http://www.google.com/ig/api?&weather=beijing
2，使用DOM解析XML
String weather = ""; String url = "[url=http://www.google.com/ig/api?&weather=beijing]http://www.google.com/ig/api?&weather=beijing[/url]"; DefaultHttpClient client = new DefaultHttpClient(); HttpUriRequest req = new HttpGet(url); HttpResponse resp = client.execute(req); HttpEntity ent = resp.getEntity(); InputStream stream = ent.getContent(); DocumentBuilder b = DocumentBuilderFactory.newInstance().newDocumentBuilder(); Document d = b.parse(new InputSource(stream)); NodeList n = d.getElementsByTagName("forecast_conditions"); for (int i = 0; i < n.getLength(); i++) { weather += n.item(i).getChildNodes().item(0).getAttributes().item(0).getNodeValue(); weather += ", "; weather += (Integer.parseInt(n.item(i).getChildNodes().item(1).getAttributes().item(0).getNodeValue()) - 32) * 5 / 9; weather += " ~ "; weather += (Integer.parseInt(n.item(i).getChildNodes().item(2).getAttributes().item(0).getNodeValue()) - 32) * 5 / 9; weather += ", "; weather += n.item(i).getChildNodes().item(4).getAttributes().item(0).getNodeValue(); weather += "\n"; }
3，另起Thread处理Web请求
new Thread() { public void run() { try { // ... } catch (Exception e) { e.printStackTrace(); } } }.start();
4，使用Handler传递Thread处理结果到UI主Thread
h = new Handler() { public void handleMessage(Message msg) { tv.setText((String)msg.obj); } }; new Thread() { // ... Message msg = h.obtainMessage(1, 1, 1, weather); h.sendMessage(msg); }
5，完整代码
package com.hideto.weatherforecast; import java.io.InputStream; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.client.methods.HttpGet; import org.apache.http.client.methods.HttpUriRequest; import org.apache.http.impl.client.DefaultHttpClient; import org.w3c.dom.Document; import org.w3c.dom.NodeList; import org.xml.sax.InputSource; import android.app.Activity; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.widget.TextView; public class WeatherForecast extends Activity { public TextView tv; public Handler h; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); tv = new TextView(this); tv.setText("Loading..."); setContentView(tv); h = new Handler() { public void handleMessage(Message msg) { tv.setText((String)msg.obj); } }; new Thread() { public void run() { try {
String weather = ""; String url = "[url=http://www.google.com/ig/api?&weather=beijing]http://www.google.com/ig/api?&weather=beijing[/url]"; DefaultHttpClient client = new DefaultHttpClient(); HttpUriRequest req = new HttpGet(url); HttpResponse resp = client.execute(req); HttpEntity ent = resp.getEntity(); InputStream stream = ent.getContent(); DocumentBuilder b = DocumentBuilderFactory.newInstance().newDocumentBuilder(); Document d = b.parse(new InputSource(stream)); NodeList n = d.getElementsByTagName("forecast_conditions");
for (int i = 0; i < n.getLength(); i++) { weather += n.item(i).getChildNodes().item(0).getAttributes().item(0).getNodeValue();
weather += ", "; weather += (Integer.parseInt(n.item(i).getChildNodes().item(1).getAttributes().item(0).getNodeValue()) - 32) * 5 / 9; weather += " ~ ";
weather += (Integer.parseInt(n.item(i).getChildNodes().item(2).getAttributes().item(0).getNodeValue()) - 32) * 5 / 9; weather += ", "; weather += n.item(i).getChildNodes().item(4).getAttributes().item(0).getNodeValue(); weather += "\n"; } Message msg = h.obtainMessage(1, 1, 1, weather); h.sendMessage(msg); } catch (Exception e) { e.printStackTrace(); } } }.start(); } }
6，修改AndroidManifest.xml加上INTERNET访问权限
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="[url=http://schemas.android.com/apk/res/android]http://schemas.android.com/apk/res/android[/url]" package="com.hideto.weatherforecast" android:versionCode="1" android:versionName="1.0.0"> <uses-permission android:name="android.permission.INTERNET"></uses-permission> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".WeatherForecast" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest>
