我假设你有另一个ViewModel与ProductCategoryViewModel对象的集合?如果是这样,我认为可以有另一个只有活跃的产品类别的集合。我不确定您需要单独的服务方法,因为您可以根据Active值过滤您的产品类别集合。
如果这个视图模型将被称为ProductCategoriesViewModel,它可能是这样的:
using System.Collections.Generic;
using System.Linq;
using GalaSoft.MvvmLight;
namespace OCEAN.EPP.ViewModel
{
public class ProductCategoriesViewModel : ViewModelBase
{
public ProductCategoriesViewModel()
{
if (IsInDesignMode)
{
ProductCategories = new List<ProductCategoryViewModel>
{
new ProductCategoryViewModel { Active = false },
new ProductCategoryViewModel { Active = false },
new ProductCategoryViewModel { Active = true },
new ProductCategoryViewModel { Active = true },
};
}
else
{
// Code runs "for real": Connect to service, etc...
}
}
public const string ProductCategoriesPropertyName = "ProductCategories";
private List<ProductCategoryViewModel> _productCategories = new List<ProductCategoryViewModel>();
public List<ProductCategoryViewModel> ProductCategories
{
get { return _productCategories; }
set
{
if (_productCategories == value)
return;
_productCategories = value;
FilterActiveProductCategories();
RaisePropertyChanged(ProductCategoriesPropertyName);
}
}
public const string ActiveProductCategoriesPropertyName = "ActiveProductCategories";
private List<ProductCategoryViewModel> _activeProductCategories = new List<ProductCategoryViewModel>();
public List<ProductCategoryViewModel> ActiveProductCategories
{
get { return _activeProductCategories; }
set
{
if (_activeProductCategories == value)
return;
_activeProductCategories = value;
RaisePropertyChanged(ActiveProductCategoriesPropertyName);
}
}
private void FilterActiveProductCategories()
{
ActiveProductCategories = ProductCategories.Where(pc => pc.Active).ToList();
}
}
}