Android实现widget定时更新
在开发Android的widget时，第一个需要解决的问题就是怎么实现让widget定时更新，在查阅比较多的资料后，一般情况用Service在后台更新，废话不多说，贴代码如下：
Widget:
publicclassNewsWidgetProviderextendsAppWidgetProvider{
@Override
publicvoidonDeleted(Contextcontext,int[]appWidgetIds){
}
@Override
publicvoidonDisabled(Contextcontext){
//TODOAuto-generatedmethodstub
super.onDisabled(context);
}
@Override
publicvoidonEnabled(Contextcontext){
//TODOAuto-generatedmethodstub
super.onEnabled(context);
}
@Override
publicvoidonUpdate(Contextcontext,AppWidgetManagerappWidgetManager,int[]appWidgetIds){
NewsService.updateAppWidgetIds(appWidgetIds);
context.startService(newIntent(context,NewsService.class));
}
publicstaticRemoteViewsupdateAppWidget(Contextcontext,List<RssNews>list){
RemoteViewsviews=newRemoteViews(context.getPackageName(),R.layout.appwidget_layout);
if(list.size()>3){
views.setTextViewText(R.id.textView01,list.get(0).title);
views.setTextViewText(R.id.textView02,list.get(1).title);
views.setTextViewText(R.id.textView03,list.get(2).title);
}
IntentdetailIntent=newIntent(context,NewsSiteList.class);
PendingIntentpending=PendingIntent.getActivity(context,0,detailIntent,0);
views.setOnClickPendingIntent(R.id.textView01,pending);
views.setOnClickPendingIntent(R.id.textView02,pending);
views.setOnClickPendingIntent(R.id.textView03,pending);
returnviews;
}
@Override
publicvoidonReceive(Contextcontext,Intentintent){
super.onReceive(context,intent);
}
}
Service:
publicclassNewsServiceextendsServiceimplementsRunnable{
privatestaticfinalStringTAG="NewsService";
privatestaticQueue<Integer>sAppWidgetIds=newLinkedList<Integer>();
publicstaticfinalStringACTION_UPDATE_ALL="com.xxxx.news.UPDATE_ALL";
privatestaticbooleansThreadRunning=false;
privatestaticObjectsLock=newObject();
@Override
publicIBinderonBind(Intentintent){
returnnull;
}
publicstaticvoidupdateAppWidgetIds(int[]appWidgetIds){
synchronized(sLock){
for(intappWidgetId:appWidgetIds){
sAppWidgetIds.add(appWidgetId);
}
}
}
publicstaticintgetNextWidgetId(){
synchronized(sLock){
if(sAppWidgetIds.peek()==null){
returnAppWidgetManager.INVALID_APPWIDGET_ID;
}else{
returnsAppWidgetIds.poll();
}
}
}
privatestaticbooleanhasMoreUpdates(){
synchronized(sLock){
booleanhasMore=!sAppWidgetIds.isEmpty();
if(!hasMore){
sThreadRunning=false;
}
returnhasMore;
}
}
@Override
publicvoidonCreate(){
super.onCreate();
}
@Override
publicvoidonStart(Intentintent,intstartId){
super.onStart(intent,startId);
if(null!=intent){
if(ACTION_UPDATE_ALL.equals(intent.getAction())){
AppWidgetManagerwidget=AppWidgetManager.getInstance(this);
updateAppWidgetIds(widget.getAppWidgetIds(newComponentName(this,NewsWidgetProvider.class)));
}
}
synchronized(sLock){
if(!sThreadRunning){
sThreadRunning=true;
newThread(this).start();
}
}
}
@Override
publicvoidrun(){
SharedPreferencessetting=getSharedPreferences("com.xxxx.news_preferences",0);
StringupdateTime=setting.getString("list_time","1800000");
StringupdateUrl=setting.getString("list_site","xxxxxxxxx");
AppWidgetManagerappWidgetManager=AppWidgetManager.getInstance(this);
RemoteViewsupdateViews=null;
while(hasMoreUpdates()){
intappWidgetId=getNextWidgetId();
List<RssNews>listNews=NewsContenttList.getNewsList(updateUrl);
if(listNews!=null){
updateViews=NewsWidgetProvider.updateAppWidget(this,listNews);
}
if(updateViews!=null){
appWidgetManager.updateAppWidget(appWidgetId,updateViews);
}
}
IntentupdateIntent=newIntent(ACTION_UPDATE_ALL);
updateIntent.setClass(this,NewsService.class);
PendingIntentpending=PendingIntent.getService(this,0,updateIntent,0);
Timetime=newTime();
longnowMillis=System.currentTimeMillis();
time.set(nowMillis+Long.parseLong(updateTime));
longupdateTimes=time.toMillis(true);
Log.d(TAG,"requestnextupdateat"+updateTimes);
AlarmManageralarm=(AlarmManager)getSystemService(Context.ALARM_SERVICE);
alarm.set(AlarmManager.RTC_WAKEUP,updateTimes,pending);
stopSelf();
}
}