使用可以更新UI的ScheduledExecutorService重复执行任务

Question

我正在尝试在我的应用程序中每2分钟执行一次任务，在我阅读了一些实现方法后，我选择使用ScheduledExecutorService，但我可以让它更新UI。我做错了什么？

以下是代码：

public class ScheduledTask {

private final String TAG="ScheduledTask";
private final ScheduledExecutorService scheduler =
         Executors.newScheduledThreadPool(1);
private Context context;
private Activity activity;

public ScheduledTask(Context c, Activity a)
{

    this.context=c;
    this.activity=a;
}

 public void RefreshMapPeriodically() 
 {

     final ScheduledFuture refreshHandle =
       scheduler.scheduleAtFixedRate(new Runnable() 
     {
           public void run() 
          { 

               //iau din baza de date sqlLite locala semnele apropiate de locatia mea
               NotificationAdministration notify=new NotificationAdministration(context);
               final ArrayList<SpeedRestriction> lista=notify.getNotificationFromLocalArea(MainActivity.CURRENT_LOCATION.getLatitude(), MainActivity.CURRENT_LOCATION.getLongitude());
               Log.i(TAG,"Run! Preluare din db");



               if(activity !=null)
               {
                   // If you need update UI, simply do this:
                   ((Activity)context).runOnUiThread(new Runnable() {
                       public void run() 
                       {
                           //le adaug pe harta
                            UpdateLocalMap.setSpeedMarkers(lista,MainActivity.getGoogleMap() , MainActivity.getMarkere());
                       }
                   });
               }
          }
     }, 0, 1, MINUTES);

     scheduler.schedule(new Runnable() {
       public void run() 
       { 
           refreshHandle.cancel(true); 
       }
     }, 60 * 60 * 2, SECONDS);
   }

我从MainActivity中调用它

ScheduledTask doRefresh=new ScheduledTask(context,this);
             doRefresh.RefreshMapPeriodically();