基于Kendo GridViewColumn创建WPF Telerik自定义网格列求助

Got it, let's walk through finishing your custom MultiDropDownColumn step by step. I'll cover the column implementation, XAML setup, and ViewModel adjustments to make everything work seamlessly.

1. Finalize the Custom MultiDropDownColumn Class #

First, let's polish your MultiDropDownColumn to support multi-select functionality properly. We'll add necessary dependency properties and ensure the cell element binds correctly to your data:

using Telerik.Windows.Controls;
using Telerik.Windows.Controls.GridView;
using System.Windows;

public class MultiDropDownColumn : GridViewBoundColumnBase
{
    // Dependency property for dropdown options
    public static readonly DependencyProperty ItemsSourceProperty =
        DependencyProperty.Register(nameof(ItemsSource), typeof(object), typeof(MultiDropDownColumn), new PropertyMetadata(null));

    // Dependency property for selected items (multi-select)
    public static readonly DependencyProperty SelectedItemsProperty =
        DependencyProperty.Register(nameof(SelectedItems), typeof(object), typeof(MultiDropDownColumn), new PropertyMetadata(null));

    public object ItemsSource
    {
        get => GetValue(ItemsSourceProperty);
        set => SetValue(ItemsSourceProperty, value);
    }

    public object SelectedItems
    {
        get => GetValue(SelectedItemsProperty);
        set => SetValue(SelectedItemsProperty, value);
    }

    // Render the dropdown in view mode
    public override FrameworkElement CreateCellElement(GridViewCell cell, object dataItem)
    {
        var multiDropDown = new RadMultiColumnComboBox();
        
        // Bind dropdown options to the column's ItemsSource
        multiDropDown.SetBinding(RadMultiColumnComboBox.ItemsSourceProperty, 
            new System.Windows.Data.Binding(nameof(ItemsSource)) { Source = this });
        
        // Bind selected items to the data item's property (from DataMemberBinding)
        multiDropDown.SetBinding(RadMultiColumnComboBox.SelectedItemsProperty, 
            this.DataMemberBinding);
        
        // Configure multi-select behavior
        multiDropDown.IsEditable = false;
        multiDropDown.SelectionMode = Telerik.Windows.Controls.SelectionMode.Multiple;
        multiDropDown.DisplayMemberPath = "Name"; // Set to your contest model's display property
        
        return multiDropDown;
    }

    // Optional: Auto-open dropdown when entering edit mode
    protected override FrameworkElement PrepareCellForEdit(GridViewCell cell, RoutedEventArgs editingEventArgs)
    {
        var multiDropDown = cell.Content as RadMultiColumnComboBox;
        multiDropDown?.IsDropDownOpen = true;
        return base.PrepareCellForEdit(cell, editingEventArgs);
    }

    // Tell the grid the data type for filtering/sorting
    public override System.Type GetColumnDataType()
    {
        return typeof(System.Collections.IEnumerable);
    }
}

Key details:

• Added ItemsSource to bind your CmbContest collection directly to the column
• Used Telerik's native RadMultiColumnComboBox for built-in multi-select support
• Linked the dropdown's selected items to your data item's property via DataMemberBinding

2. Update Your XAML Configuration #

Now use the custom column in your RadGridView, making sure to bind all required properties:

<telerik:RadGridView x:Name="ContestGridView" ItemsSource="{Binding YourGridData}">
    <telerik:RadGridView.Columns>
        <!-- Regular data column example -->
        <telerik:GridViewDataColumn Header="Item Name" DataMemberBinding="{Binding ItemName}" />
        
        <!-- Custom MultiDropDownColumn -->
        <local:MultiDropDownColumn 
            Header="Selected Contests" 
            DataMemberBinding="{Binding SelectedContests}"
            ItemsSource="{Binding CmbContest}" />
    </telerik:RadGridView.Columns>
</telerik:RadGridView>

Replace local: with your actual namespace where the MultiDropDownColumn is defined.

3. Adjust Your ViewModel #

Ensure your ViewModel has the necessary collections and properties to support the custom column:

using System.Collections.ObjectModel;
using Telerik.Windows.Controls;

public class MainViewModel : ViewModelBase
{
    // Collection of contests for dropdown options
    public ObservableCollection<Contest> CmbContest { get; set; }

    // Collection of items displayed in the grid
    public ObservableCollection<GridItem> YourGridData { get; set; }

    public MainViewModel()
    {
        // Initialize collections
        CmbContest = new ObservableCollection<Contest>();
        YourGridData = new ObservableCollection<GridItem>();
        
        // Populate sample data
        CmbContest.Add(new Contest { Id = 1, Name = "Spring Contest" });
        CmbContest.Add(new Contest { Id = 2, Name = "Summer Contest" });
        CmbContest.Add(new Contest { Id = 3, Name = "Fall Contest" });
        
        YourGridData.Add(new GridItem { ItemName = "Entry 1", SelectedContests = new ObservableCollection<Contest>() });
    }
}

// Grid data item class
public class GridItem : ViewModelBase
{
    public string ItemName { get; set; }
    
    private ObservableCollection<Contest> _selectedContests;
    public ObservableCollection<Contest> SelectedContests
    {
        get => _selectedContests;
        set
        {
            _selectedContests = value;
            OnPropertyChanged();
        }
    }
}

// Contest model class
public class Contest
{
    public int Id { get; set; }
    public string Name { get; set; }
}

Quick Troubleshooting Tips #

• If dropdown items don't appear: Verify the ItemsSource binding on the custom column points to your CmbContest collection
• If selections don't save: Ensure your SelectedContests property uses ObservableCollection (or implements INotifyCollectionChanged)
• To customize dropdown columns: Add RadMultiColumnComboBox.Columns in the CreateCellElement method to define custom grid columns for the dropdown

内容的提问来源于stack exchange，提问作者MikkaRin