android之后台定时更新ui天气【Timer、service、broadcast、activity】

浏览数：250 / 时间：2015年06月11日

这个案例只是为了关联各个知识点，在实际开发中还有待优化

项目结构分析：技术分享

Weather实体类：用来存放我们的天气实体

WeatherManager: 用来操作Weather

MainActivity:主acaitivy

CityWeatherService:定时轮询来更新前台的信息

原理比较简单直接贴出代码：

Weather:

[java] view plain copy

package com.example.weatherdemo;
public class Weather
{
private String cityName;
private String cityData;
private String cityWeath;
private String cityWinder;
private String cityImg;
public Weather(){
}
public Weather(String cityName,String cityData,String cityWeath,String cityWinder,String cityImg){
this.cityName = cityName;
this.cityData = cityData;
this.cityWeath = cityWeath;
this.cityWinder = cityWinder;
this.cityImg = cityImg;
}
public String getCityName()
{
return cityName;
}
public void setCityName(String cityName)
{
this.cityName = cityName;
}
public String getCityData()
{
return cityData;
}
public void setCityData(String cityData)
{
this.cityData = cityData;
}
public String getCityWeath()
{
return cityWeath;
}
public void setCityWeath(String cityWeath)
{
this.cityWeath = cityWeath;
}
public String getCityWinder()
{
return cityWinder;
}
public void setCityWinder(String cityWinder)
{
this.cityWinder = cityWinder;
}
public String getCityImg()
{
return cityImg;
}
public void setCityImg(String cityImg)
{
this.cityImg = cityImg;
}
}

WeatherManager:

[java] view plain copy

package com.example.weatherdemo;
import org.json.JSONException;
import org.json.JSONObject;
public class WeatherManager
{
Weather weather;
public void setWeather(String jsonString){
try
{
JSONObject jsonObject = new JSONObject( jsonString );
JSONObject object = jsonObject.getJSONObject( "weatherinfo" );
String cityName = object.getString( "city" );
String cityData = object.getString( "date_y" );
String cityWeath = object.getString( "weather1" );
String cityWinder = object.getString( "wind1" );
String cityImg = object.getString( "img1" );
weather = new Weather( cityName, cityData, cityWeath, cityWinder, cityImg );
}
catch (JSONException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public Weather getWeather(){
return weather;
}
}

CityWeatherService:

[java] view plain copy

package com.example.weatherdemo;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Timer;
import java.util.TimerTask;
import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.Intent;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.util.Log;
public class CityWeatherService extends Service
{
private static final int UPDATAWEATHER = 0X10;
private final int GOTOBROADCAST = 0X20;
public static final String BROADCASTACTION = "com.jone.broad";
Timer timer;
@Override
public IBinder onBind(Intent arg0)
{
// TODO Auto-generated method stub
return null;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId)
{
// updateWeather();
timer = new Timer();
timer.schedule( new TimerTask()
{
@Override
public void run()
{
// 定时更新
String jsonString = getWeather();
// 发送广播
Intent intent = new Intent();
intent.setAction( BROADCASTACTION );
intent.putExtra( "jsonstr", jsonString );
sendBroadcast( intent );
// Message msg = handler.obtainMessage();
// msg.what = UPDATAWEATHER;
// handler.sendMessage( msg );
}
}, 0, 20 * 1000 );
return super.onStartCommand( intent, flags, startId );
}
private String getWeather()
{
String srsString = "";
try
{
srsString = getJsonStringGet( "http://m.weather.com.cn/data/101250101.html" );
}
catch (Exception e)
{
// TODO Auto-generated catch block
e.printStackTrace();
Log.i( "tag",e.getMessage() );
}
return srsString;
}
public String getJsonStringGet(String uri) throws Exception
{
String result = null;
URL url = new URL( uri );
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout( 6 * 1000 );// 设置连接超时
Log.i( "msg", conn.getResponseCode() + "???????" );
if (conn.getResponseCode() == 200)
{
Log.i( "msg", "成功" );
InputStream is = conn.getInputStream();// 得到网络返回的输入流
result = readData( is, "UTF-8" );
}
else
{
Log.i( "msg", "失败" );
result = "";
}
conn.disconnect();
return result;
}
private String readData(InputStream inSream, String charsetName) throws Exception
{
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = -1;
while ((len = inSream.read( buffer )) != -1)
{
outStream.write( buffer, 0, len );
}
byte[] data = outStream.toByteArray();
outStream.close();
inSream.close();
return new String( data, charsetName );
}
@Override
public void onDestroy()
{
// TODO Auto-generated method stub
super.onDestroy();
if(timer != null){
timer.cancel();
}
}
}