I am using nopCommerce 3.10. I am making a Plugin.

I have used Telerik-grid to list Pictures of Product.Product Pictures displayed successfully in telerik-grid.i have used edit and delete button for each picture in telerik-grid. Delete Operation works properly.But inline editing does not work.When i enter value in DisplayOrder field and try to Update record, Update operation does not performs.

_CreateOrUpdate.Pictures.cshtml

@using Telerik.Web.Mvc.UI;

    <div>
        @(Html.Telerik().Grid<ProductPictureModel>()
                    .Name("productpictures-grid")
                    .DataKeys(x =>
                    {
                        x.Add(y => y.Id).RouteKey("Id");
                    })
                    .Columns(columns =>
                    {
                        columns.Bound(x => x.PictureUrl)
                            .ClientTemplate("<a href='<#= PictureUrl #>' target='_blank'><img alt='<#= PictureId #>' src='<#= PictureUrl #>' width='150' /><a/>")
                            .ReadOnly();
                        columns.Bound(x => x.DisplayOrder);
                        columns.Command(commands =>
                        {
                            commands.Edit().Text(T("Admin.Common.Edit").Text);
                            commands.Delete().Text(T("Admin.Common.Delete").Text);
                        });

                    })
                    .Editable(x =>
                    {
                        x.Mode(GridEditMode.InLine);
                    })
                    .DataBinding(dataBinding =>
                    {
                        dataBinding.Ajax().Select("PictureList"Product", new { productId = Model.Id })
                            .Update("PictureUpdate", "Product")
                            .Delete("DeletePicture", "Product");
                    })
                    .EnableCustomBinding(true))
    </div>


Update Method:

[GridAction(EnableCustomBinding = true)]
        public ActionResult PictureUpdate(ProductPictureModel model, GridCommand command)
        {
            if (!_permissionService.Authorize(StandardPermissionProvider.ManageProducts))
                return AccessDeniedView();

            var productPicture = _productService.GetProductPictureById(model.Id);
            if (productPicture == null)
                throw new ArgumentException("No product picture found with the specified id");

            //a vendor should have access only to his products
            if (_workContext.CurrentVendor != null)
            {
                var product = _productService.GetProductById(productPicture.ProductId);
                if (product != null && product.VendorId != _workContext.CurrentVendor.Id)
                {
                    return Content("This is not your product");
                }
            }

            productPicture.DisplayOrder = model.DisplayOrder;
            _productService.UpdateProductPicture(productPicture);

            return ProductPictureList(command, productPicture.ProductId);
        }


What should i do to overcome this problem?

Thank you in advance