public void start(Calendar startTime,Calendar endTime){
  if (startTime == null || endTime == null || startTime.after(endTime)) {
    throw new IllegalArgumentException("startTime and endTime cannot be null and startTime must be before endTIme.");
  }
  mStartTime=startTime;
  start(endTime);
}

public void start ( Calendar startTime , Calendar endTime ) { if ( startTime == null || endTime == null || startTime . after ( endTime ) ) { throw new IllegalArgumentException ( "startTime and endTime cannot be null and startTime must be before endTIme." ) ; } mStartTime = startTime ; start ( endTime ) ; }
only for use with with tickcircleduration = total_time
