Question

我有一个CollectionViewSource，其中定义了排序说明，但我想根据用户可以选择的单独下拉列表更改这些排序说明。理想情况下，我希望在没有代码隐藏的情况下实现所有这些。

        <CollectionViewSource x:Key="SortedPeople" Source="{Binding People}">
<!--sort by first name then last name -->
            <CollectionViewSource.SortDescriptions> 
                <scm:SortDescription PropertyName="FirstName"/>
                <scm:SortDescription PropertyName="LastName"/>
            </CollectionViewSource.SortDescriptions>
<!-- another way to do this?
<!--sort by last name then first name -->
            <CollectionViewSource.SortDescriptions> 
                <scm:SortDescription PropertyName="LastName"/>
                <scm:SortDescription PropertyName="FirstName"/>
            </CollectionViewSource.SortDescriptions>-->
        </CollectionViewSource>

(...xaml for drop down box which sets which set of sort descriptions to use...)

有可能吗？

Answer 1

假设你有一个带有多个排序参数的组合框。

<ComboBox ItemsSource="{Binding SortByItemList}"
          SelectedItem="{Binding SelectedSortByItem,Mode=TwoWay}"/>

在视图模型中，输入：

public string SelectedSortByItem
    {
        get
        {
            return _selectedSortByItem;
        }

        set
        {
            _selectedSortByItem = value;
            OnSelectedSortByItemChanged(People, SelectedSortByItem);
            RaisePropertyChanged();
        }
    }

public IList<People> OnSelectedSortByItemChanged(IList<People> items, string sortBy)
    {
        if (items == null || !items.Any())
        {
            return items;
        }

        var itemsToSort = items.ToList();

        if (sortBy == "FirstName")
        {
            return Sort(itemsToSort, "FirstName");
        }
        else if (sortBy == "LastName")
        {
            return Sort(itemsToSort, "LastName");
        }
        // put as many properties as you want here
  }

private static List<People> Sort(
            List<People> itemsToSort,
            string propertyPath,
            ListSortDirection sortDirection = ListSortDirection.Ascending)
{
   // put your sorting logic here.
}

希望这有帮助。

在CollectionViewSource中使用多个排序描述？

1 个答案: