async Task LoadPickerSourceAsync()
        {
            PickerItemModel pItem = new PickerItemModel();

            #region 讀取請假假別
            await leaveCategoryService.ReadFromFileAsync();

            LeaveCategoryItemsSource.Clear();
            foreach (var item in leaveCategoryService.Items)
            {
                pItem = new PickerItemModel()
                {
                    Id   = item.Id,
                    Name = item.Name,
                };
                LeaveCategoryItemsSource.Add(pItem);
            }
            #endregion

            #region 讀取使用者
            await myUserService.ReadFromFileAsync();

            MyUserItemsSource.Clear();
            foreach (var item in myUserService.Items)
            {
                pItem = new PickerItemModel()
                {
                    Id   = item.Id,
                    Name = item.Name,
                };
                MyUserItemsSource.Add(pItem);
            }
            #endregion
        }
        async Task LoadPickerSourceAsync()
        {
            PickerItemModel pItem = new PickerItemModel();

            #region 讀取 專案
            await projectService.ReadFromFileAsync();

            ProjectItemsSource.Clear();
            foreach (var item in projectService.Items)
            {
                pItem = new PickerItemModel()
                {
                    Id   = item.Id,
                    Name = item.Name,
                };
                ProjectItemsSource.Add(pItem);
            }
            #endregion
        }