在開啟一個服務之前應該判斷該服務知否已經在執行
 
//本方法判斷自己些的一個Service-->com.android.controlAddFunctions.PhoneService是否已經執行
public static boolean isWorked()
 {
  ActivityManager myManager=(ActivityManager)context.getSystemService(Context.ACTIVITY_SERVICE);
  ArrayList<RunningServiceInfo> runningService = (ArrayList<RunningServiceInfo>) myManager.getRunningServices(30);
  for(int i = 0 ; i<runningService.size();i++)
  {
   if(runningService.get(i).service.getClassName().toString().equals("com.android.controlAddFunctions.PhoneService"))
   {
    return true;
   }
  }
  return false;
 }