自定义 CollectionViewType 不支持使用 shift 键进行多选 [英] Custom CollectionViewType does not support multiple selection using shift key

问题描述

在 Window 中，我使用自定义 CollectionViewType 和 CollectionViewSource(EmployeeCollectionView).

In a Window, I group items in a ListBox using a custom CollectionViewType with a CollectionViewSource (EmployeeCollectionView).

MainWindow.xaml:

<Window x:Class="ListBoxSelectionMode.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:ListBoxSelectionMode">
<Window.Resources>
    <CollectionViewSource x:Key="EmployeesSource" Source="{Binding Employees}" CollectionViewType="local:EmployeeCollectionView" />

    <DataTemplate x:Key="EmployeeTemplate">
        <StackPanel Orientation="Horizontal">
            <TextBlock Text="{Binding FirstName}" />
            <TextBlock Text="{Binding LastName}" />
        </StackPanel>
    </DataTemplate>
</Window.Resources>

<ListBox ItemsSource="{Binding Source={StaticResource EmployeesSource}}"
         ItemTemplate="{StaticResource EmployeeTemplate}"
         SelectionMode="Extended">
    <ListBox.GroupStyle>
        <x:Static Member="GroupStyle.Default"/>
    </ListBox.GroupStyle>
</ListBox>

MainWindow.xaml.cs:

public partial class MainWindow : Window
{
    public IEnumerable<Employee> Employees { get; set; }

    public MainWindow()
    {
        InitializeComponent();

        Employees = new List<Employee>
        {
            new Employee { FirstName = "FirstName1", LastName = "LastName1", HireDate = new DateTime(1970, 1, 1) },
            new Employee { FirstName = "FirstName2", LastName = "LastName2", HireDate = new DateTime(1970, 1, 1) },
            new Employee { FirstName = "FirstName3", LastName = "LastName3", HireDate = new DateTime(1980, 1, 1) },
            new Employee { FirstName = "FirstName4", LastName = "LastName4", HireDate = new DateTime(1980, 1, 1) },
            new Employee { FirstName = "FirstName5", LastName = "LastName5", HireDate = new DateTime(1990, 1, 1) },
            new Employee { FirstName = "FirstName6", LastName = "LastName6", HireDate = new DateTime(1990, 1, 1) }
        };

        DataContext = this;
    }
}

EmployeeCollectionView.cs:

class EmployeeCollectionView : ListCollectionView
{
    private readonly IList<EmployeeCollectionViewGroup> _groups;
    public override ReadOnlyObservableCollection<object> Groups
    {
        get { return new ReadOnlyObservableCollection<object>(new ObservableCollection<object>(_groups)); }
    }

    public EmployeeCollectionView(IList list)
        : base(list)
    {
        _groups = list
             .OfType<Employee>()
            .GroupBy(x => x.HireDate)
            .Select(x => new EmployeeCollectionViewGroup(x.Key, x))
            .ToList();
    }
}

EmployeeCollectionViewGroup.cs:

class EmployeeCollectionViewGroup : CollectionViewGroup
{
    public EmployeeCollectionViewGroup(object name, IEnumerable<object> protectedItems)
        : base(name)
    {
        foreach (var protectedItem in protectedItems)
            ProtectedItems.Add(protectedItem);
    }

    public override bool IsBottomLevel
    {
        get { return true; }
    }
}

问题:为什么我不能使用 SHIFT 键选择多个项目?

Question: Why can't I select multiple items using SHIFT key?

使用 CTRLworks 进行多项选择.

Multiple selection using CTRLworks.

推荐答案

您是否尝试过按下 CTRL 键而不是 SHIFT 键?在您的列表声明之后移动 InitializeComponent.

Have you tried pushing down the CTRL key instead of SHIFT key? Also move InitializeComponent after the declaration of your List.

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