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
        }
        public async void OnNavigatedTo(INavigationParameters parameters)
        {
            await LoadPickerSourceAsync();

            var fooObject = parameters.GetValue <LeaveFormDto>(MagicStringHelper.CurrentSelectdItemParameterName);

            fooObject.SetDate();
            SelectedItem     = fooObject;
            CrudAction       = parameters.GetValue <string>(MagicStringHelper.CrudActionName);
            ShowDeleteButton = true;
            if (CrudAction == MagicStringHelper.CrudAddAction)
            {
                ShowDeleteButton = false;
            }

            #region 進行選單初始化
            #region 假別
            if (SelectedItem.LeaveCategoryId >= 0)
            {
                LeaveCategorySelectedItem = LeaveCategoryItemsSource
                                            .FirstOrDefault(x => x.Id == SelectedItem.LeaveCategoryId);
            }
            #endregion
            #region 申請人
            if (SelectedItem.MyUserId >= 0)
            {
                MyUserSelectedItem = MyUserItemsSource
                                     .FirstOrDefault(x => x.Id == SelectedItem.MyUserId);
            }
            #endregion
            #region 代理人
            if (SelectedItem.AgentId >= 0)
            {
                AgentSelectedItem = MyUserItemsSource
                                    .FirstOrDefault(x => x.Id == SelectedItem.AgentId);
            }
            #endregion
            #endregion
        }