How to implement a drop-down editor with multiple columns in XAF Blazor

Ok, tks, i am try it.

I also need this capability so I thought I would share a sample demostrating the approach I took.

1. You'll need a new Property Editor for each use-case since you'll be adding Business Object/Entity specific and property specific information (DxListEditorColumn, etc)
2. You want to set your property editor to the Navigation Property (Order), not the primative property Foreign Key property (OrderID).
3. You want to use the DxComboBox's SelectedItemChanged in-lieu of onchange as outlined in the custom component guide to invoke your ComponentModel's SetValueFromUI method.

Hopefully it helps.
Adam

Thanks for sharing your solution with the XAF community, Adam! I've reshared your post in our developer groups.

Could You help me figure out how this would work when using XPO ?
I've encountered an issue - with the "orderService" and how to register it in the IoC, when it's using xpo.

Would I need to supply an IObjectSpace to it as a parameter instead of DataContext ? or an ISession ?
How would I instruct the IoC to take the Iobjectspace of the current view ?

Hello,

It is possible to set up the DxComboBox data source in the OrderEditor property editor instead of using orderService.

To do this, define an Orders property in the OrderEditorModel component model:

C#
using System;
using System.Collections.Generic;
using DevExpress.ExpressApp.Blazor.Components.Models;
using MultiColumnLookupListView.Module.BusinessObjects;

namespace MultiColumnLookupListView.Module.Blazor.ComponentModels {
    public class OrderEditorModel : ComponentModelBase {
        public IList<Order> Orders {
            get => GetPropertyValue<IList<Order>>();
            set => SetPropertyValue(value);
        }
        //...
    }
}

Then, use it in the OrderEditorRenderer component:

Razor
...
<DxComboBox Data="@ComponentModel.Orders"
...

After that, implement the IComplexViewItem interface in the OrderEditor property editor to access an object space. Set the Orders property, for example, in the following way:

C#
using System;
using DevExpress.ExpressApp;
using DevExpress.ExpressApp.Blazor.Editors;
using DevExpress.ExpressApp.Blazor.Editors.Adapters;
using DevExpress.ExpressApp.Editors;
using DevExpress.ExpressApp.Model;
using MultiColumnLookupListView.Module.Blazor.ComponentAdapters;
using MultiColumnLookupListView.Module.Blazor.ComponentModels;
using MultiColumnLookupListView.Module.BusinessObjects;

namespace MultiColumnLookupListView.Module.Blazor.Editors {
    [PropertyEditor(typeof(Order), false)]
    public class OrderEditor : BlazorPropertyEditorBase, IComplexViewItem {
        private IObjectSpace objectSpace;
        void IComplexViewItem.Setup(IObjectSpace objectSpace, XafApplication application) {
            this.objectSpace = objectSpace;
        }
        protected override void OnControlCreated() {
            base.OnControlCreated();
            ((OrderEditorAdapter)Control).ComponentModel.Orders = objectSpace.GetObjects<Order>();
        }
        //...
    }
}

Please note that this is only a possible demonstration, and additional testing is required. I hope you find this information helpful.

Thanks,
Ilya P

hi Ilya
public IList<Order> Orders can use IQueryable or IList<T>？Is paging supported with big data。