How to display List<object> Count in a cell

[Andrew]

In a simple table, I know I'd be able to just call Count in a cell, and there weren't any problems. However, trying to do it in a Grid has been challenging:

This is how my MVC Grid looks like:

@(Html.Kendo().Grid<ContentExternalLink>()
            .Name("issue-grid")
            .DataSource(dataSource => dataSource
            .Ajax()
            .Model(model => model.Id(x => x.LinkId))
            .Read(read => read.Action("ContentExternalLink_Read", "ContentManagement"))
            .Create(create => create.Action("ContentExternalLink_Create", "ContentManagement"))
            .Update(update => update.Action("ContentExternalLink_Update", "ContentManagement"))
            .Destroy(delete => delete.Action("ContentExternalLink_Destroy", "ContentManagement"))
            .ServerOperation(true)
            .PageSize(10))
            .Columns(columns =>
            {
                columns.Bound(x => x.LinkId).Hidden();
                columns.Bound(x => x.LinkTitle).Title("Title").Template(@<text>
                    <a href="@item.LinkUrl" taget="_blank">@item.LinkTitle</a>
                        </text>);
                columns.Bound(x => x.LinkTypeId).Title("Type");
                columns.Bound(x => x.LinkCreatedDate).Title("Created");
                columns.Bound(x => x.ContentTagAssignments.Count).Title("Tags");
                columns.Bound(x => x.LinkSource).Hidden();
                columns.Bound(x => x.LinkPhoneNumber).Hidden();
                columns.Bound(x => x.LinkDate).Hidden();
                columns.Bound(x => x.LinkCreatedDate).Hidden();
                columns.Bound(x => x.LinkModifiedDate).Hidden();
                columns.Command(command => { command.Edit(); command.Destroy(); }).Width(250);
            })
            .ToolBar(toolbar => toolbar.Create())
            .Editable(editable => editable.Mode(GridEditMode.InLine))
            .Scrollable(scr => scr.Height("auto"))
            .Sortable()
            .Pageable(pageable => pageable
                .Refresh(true)
                .PageSizes(true)
                .ButtonCount(5))
)

When I run that, I get the Javascript error: Cannot read property 'Count' of undefined.

Any ideas how to get what I want to achieve?

Thank you!
AJ

[Viktor Tachev]

Hi Andrew,

Note that the DataSource is designed to work with flat data. If you would like to show count in one of the Grid columns you can update the Model to include a field that would hold the count value. You can populate that field in the Controller when querying the data from the database. Then , you can show that field as a separate column in the Grid component.

​

columns.Bound(x => x.ContentTagAssignmentsCount).Title("Tags");

On a side note, have in mind that when using Ajax binding you should use ClientTemplate for the columns. Please check out the following article that describes the approach in more detail.

• http://docs.telerik.com/kendo-ui/aspnet-mvc/helpers/grid/faq#how-to-customize-the-way-properties-are-displayed-in-grid-bound-columns

Regards,
Viktor Tachev
Telerik by Progress