<?xml version="1.0" encoding="utf-8"?>   
<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"  
  android:minWidth="50dip"  
  android:minHeight="50dip"  
  android:updatePeriodMillis="10000"  
  
  android:initialLayout="@layout/main"  
/>   

<?xml version="1.0" encoding="utf-8"?>   
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
  android:orientation="vertical"  
  android:layout_width="fill_parent"  
  android:layout_height="fill_parent"  
  android:background="@drawable/wordcup"  
  >   
<TextView    
  android:id="@+id/wordcup"  
  android:layout_width="fill_parent"   
  android:layout_height="wrap_content"   
  android:text="@string/hello"  
  android:textSize="12px"  
  android:textColor="#ff0000"  
  />
</LinearLayout>

package com.android.tutor;   
import java.util.Calendar;   
import java.util.Date;   
import java.util.GregorianCalendar;   
import java.util.Timer;   
import java.util.TimerTask;   
import android.appwidget.AppWidgetManager;   
import android.appwidget.AppWidgetProvider;   
import android.content.ComponentName;   
import android.content.Context;   
import android.widget.RemoteViews;   
public class WidetDemo extends AppWidgetProvider {   
  /** Called when the activity is first created. */  
    
  @Override  
  public void onUpdate(Context context, AppWidgetManager appWidgetManager,   
      int[] appWidgetIds) {   
       
    Timer timer = new Timer();   
    timer.scheduleAtFixedRate(new MyTime(context,appWidgetManager), 1, 60000);   
    super.onUpdate(context, appWidgetManager, appWidgetIds);   
  }   
     
     
  private class MyTime extends TimerTask{   
    RemoteViews remoteViews;   
    AppWidgetManager appWidgetManager;   
    ComponentName thisWidget;   
       
    public MyTime(Context context,AppWidgetManager appWidgetManager){   
      this.appWidgetManager = appWidgetManager;   
      remoteViews = new RemoteViews(context.getPackageName(),R.layout.main);   
         
      thisWidget = new ComponentName(context,WidetDemo.class);   
    }   
    public void run() {   
         
      Date date = new Date();   
      Calendar calendar = new GregorianCalendar(2010,06,11);   
      long days = (((calendar.getTimeInMillis()-date.getTime())/1000))/86400;   
      remoteViews.setTextViewText(R.id.wordcup, "距离南非世界杯还有" + days+"天");   
      appWidgetManager.updateAppWidget(thisWidget, remoteViews);   
         
    }   
       
  }   
    
}  

函数调用周期

[启动 - 无confiure Activity] 
onReceive
onEnabled —— 第一个widget被显示
onReceive
onUpdate —— 刷新界面

[启动 - 带confiuration Activity] 
onReceive
onUpdate

[拖动] 
<无状态变化>

[周期更新] 
onReceive
onUpdate

[删除] 
onReceive
onDeleted —— widget被删除
onReceive
onDisabled —— 最后一个widget被移除

[启动时位置不够] 
onReceive
onEnabled
onReceive
onUpdate
onReceive
onDeleted
onReceive
onDisabled

<?xml version="1.0" encoding="utf-8"?>   
<manifest xmlns:android="http://schemas.android.com/apk/res/android"  
   package="com.android.tutor"  
   android:versionCode="1"  
   android:versionName="1.0">   
  <application android:icon="@drawable/icon" android:label="@string/app_name">   
    <receiver android:name=".WidetDemo"  
         android:label="@string/app_name">   
      <intent-filter>   
        <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />   
      </intent-filter>   
      <meta-data android:name="android.appwidget.provider"  
            android:resource="@xml/widget_provider"  
      />   
    </receiver>   
  </application>   
  <uses-sdk android:minSdkVersion="7" />   
</manifest>   

<?xml version="1.0" encoding="utf-8"?>   
<resources>   
  <string name="hello">Hello World, WidetDemo!</string>   
  <string name="app_name">DaysToWorldCup</string>   
</resources>