public List <OutlookTask> ReadAllTasksByCategory(OutlookCategory category)
        {
            List <OutlookTask> tasksInCategory = new List <OutlookTask>();

            taskAndCategoryLoader.Tasks.ForEach(item =>
            {
                if (category.Equals(item.Category))
                {
                    tasksInCategory.Add(item);
                }
            });
            return(tasksInCategory);
        }
        public ObservableCollection <OutlookTask> ReadByCategory(OutlookCategory category)
        {
            ObservableCollection <OutlookTask> tasksInCategory = loadTasks(category);

            tasksInCategory.Clear();
            List <OutlookTask> taskList = outlookService.ReadAllTasksByCategory(category);

            taskList.ForEach(item =>
            {
                if (filter(item) && (category == null || category.Equals(item.Category)))
                {
                    tasksInCategory.Add(item);
                }
            });

            return(tasksInCategory);
        }