public SelectManufacturerPageViewModel(INavigationService navigationService,
IManufacturerService manufacturerService,
IDialogService dialogService
) : base(navigationService, dialogService)
{
Title = "选择供应商";
_navigationService = navigationService;
_dialogService = dialogService;
_manufacturerService = manufacturerService;
//Load
this.Load = ManufacturersLoader.Load(async() =>
{
//重载时排它
ItemTreshold = 1;
try
{
//清除列表
Manufacturers.Clear();
var items = await GetManufacturersPage(0, PageSize);
if (items != null)
{
foreach (var item in items)
{
if (Manufacturers.Count(s => s.Id == item.Id) == 0)
{
Manufacturers.Add(item);
}
}
}
}
catch (Exception ex)
{
Crashes.TrackError(ex);
}
this.Manufacturers = new ObservableRangeCollection <ManufacturerModel>(Manufacturers);
return(Manufacturers.ToList());
});
//以增量方式加载数据
this.ItemTresholdReachedCommand = ReactiveCommand.Create(async() =>
{
using (var dig = UserDialogs.Instance.Loading("加载中..."))
{
try
{
int pageIdex = Manufacturers.Count / (PageSize == 0 ? 1 : PageSize);
var items = await GetManufacturersPage(pageIdex, PageSize);
var previousLastItem = Terminals.Last();
if (items != null)
{
foreach (var item in items)
{
if (Manufacturers.Count(s => s.Id == item.Id) == 0)
{
Manufacturers.Add(item);
}
}
if (items.Count() == 0 || items.Count() == Terminals.Count)
{
ItemTreshold = -1;
return(Manufacturers.ToList());
}
}
}
catch (Exception ex)
{
Crashes.TrackError(ex);
ItemTreshold = -1;
}
this.Manufacturers = new ObservableRangeCollection <ManufacturerModel>(Manufacturers);
return(Manufacturers.ToList());
}
}, this.WhenAny(x => x.Terminals, x => x.GetValue().Count > 0));
this.WhenAnyValue(x => x.Selecter).Throttle(TimeSpan.FromMilliseconds(500))
.Skip(1)
.Where(x => x != null)
.SubOnMainThread(async item =>
{
await _navigationService.GoBackAsync(("Manufacturer", item));
this.Selecter = null;
}).DisposeWith(DeactivateWith);
this.BindBusyCommand(Load);
}