public PerformanceEntity ActiityChange(ActivityName activityName)
 {
     WorkingActivity.GetInstance().StopTime = DateTime.Now;
     SetPerformance();
     WorkingActivity.GetInstance().StartTime    = _performance.EndTime;
     WorkingActivity.GetInstance().ActivityName = activityName;
     return(_performance);
 }
        private void SetPerformance()
        {
            var work = WorkActivityService.GetWork(
                _workEntitis,
                WorkingActivity.GetInstance().ActivityName);

            _performance = new PerformanceEntity(
                WorkingActivity.GetInstance().StartTime,
                WorkingActivity.GetInstance().StopTime,
                work,
                _user);
        }