public ReportViewModel(TaskLogApplicationService service, ReportTarget reportTarget)
        {
            ObservableCollection <PeriodViewModel> periods = new ObservableCollection <PeriodViewModel>();
            PeriodViewModel      period         = PeriodViewModel.Create(reportTarget.Period);
            var                  targets        = new ObservableCollection <TaskReportItemViewModel>();
            TaskSpecifyViewModel reportTargetVm = TaskSpecifyViewModel.Create(reportTarget.TaskSpecify);

            if (reportTarget.TaskSpecify is IndividualTaskSpecify)
            {
                foreach (var x in ((IndividualTaskSpecify)reportTarget.TaskSpecify).TargetTasks)
                {
                    targets.Add(new TaskReportItemViewModel(x.TaskKeyword, x.SearchMethod, 0));
                }
            }
            Init(service, reportTarget.Title, period, reportTargetVm, targets);
        }