对父子组合框ItemSource绑定中的子ItemSource进行排序

Question

我有一个用户控件，它包含两个组合框，用户可以在其中选择库存类别，然后选择库存项目。库存类别组合框的选定值将触发库存项目组合框列表。我遇到的问题是我不能对库存物品组合列表进行排序。当我将组合的库存类别和库存项目添加到DataContext时，我可以对库存类别进行排序，但不能对库存项目列表进行排序。代码如下所示：

Xaml：

<ComboBox Style="{DynamicResource ResourceKey=ComboBoxStyle}"
          Name="cboInventoryCategory"
          MinWidth="250"
          HorizontalAlignment="Stretch"
          ItemsSource="{Binding DataContext.InventoryCategoryList, RelativeSource={RelativeSource AncestorType=UserControl,Mode=FindAncestor}}"
          DisplayMemberPath="Category"
          SelectedValuePath="Id"
          SelectionChanged="cboInventoryCategory_SelectionChanged" />

<ComboBox Style="{DynamicResource ResourceKey=ComboBoxStyle}"
          Name="cboInventoryItem"
          MinWidth="250"
          HorizontalAlignment="Stretch"
          ItemsSource="{Binding ElementName=cboInventoryCategory,Path=SelectedItem.InventoryLists}"
          SelectedValue="{Binding Inventory_Id, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
          DisplayMemberPath="InventoryDescription"
          SelectedValuePath="InventoryId"
          SelectionChanged="cboRequestFor_SelectionChanged" />

Xaml.CS：

public Inventory()
{
    Initialize();

    var db = new DataContext();
    var viewModel = new ViewModel();

    DataContext = viewModel;
}

查看模型：

using System.Linq;
using System.Data.Linq;

public IEnumerable<InventoryCategory> InventoryCategoryList { get; set; }
//InventoryCategory is a table
//InventoryList is a view and has a primary key and an association in the dbml

public ViewModel()
{
    InventoryCategoryList_Refresh()
}

public void InventoryCategoryList_Refresh()
{

     var dataOptions = new DataLoadOptions();
     dataOptions.LoadWith<InventoryCategory>(ic => ic.InventoryLists);
     db.LoadOptions = dataOptions;

     InventoryCategoryList = db.InventoryCategories.Where(w => w.Active == true).OrderBy(o => o.Category);
}

Answer 1

必须使用.AssociateWith<>而不是.LoadWith<>

var dataOptions = new DataLoadOptions();
dataOptions.AssociateWith<InventoryCategory>(ic => ic.InventoryLists.OrderBy(o => o.InventoryDescription));
db.LoadOptions = dataOptions;

Answer 2

试试这个：

public void InventoryCategoryList_Refresh()
{

     var dataOptions = new DataLoadOptions();
     dataOptions.LoadWith<InventoryCategory>(ic => ic.InventoryLists);
     db.LoadOptions = dataOptions;

     InventoryCategoryList = db.InventoryCategories.Where(w => w.Active == true).OrderBy(o => o.Category).ThenBy(c=>c.InventoryItems);
}