Kendo UI Grid Foreign Key column empty - asp.net-mvc

Question

I have tried to follow an example to get a foreign key into a grid. I followed this example:
http://demos.telerik.com/aspnet-mvc/grid/foreignkeycolumn
I have altered it a little bit because I want to use a Popup Editor.
Here is the Grid implementation in the View.
#(Html.Kendo().Grid<Example.Web.UI.ViewModels.ExampleItem>()
.Name("ExampleGrid")
.Columns(columns =>
{
columns.Bound(p => p.Name);
columns.Bound(p => p.Label);
columns.Bound(p => p.Type);
columns.Bound(p => p.InputType);
columns.ForeignKey(p => p.ParentId, (System.Collections.IEnumerable)ViewData["items"], "Id", "Name").Title("Parent");
columns.Command(command => { command.Edit(); command.Destroy(); });
})
.Scrollable()
.Groupable()
.Sortable()
.Pageable(pageable => pageable
.Refresh(true)
.PageSizes(true)
.ButtonCount(5))
.ToolBar(toolbar => toolbar.Create())
.Editable(editable => editable.Mode(GridEditMode.PopUp))
.DataSource(dataSource => dataSource
.Ajax()
.PageSize(20)
.Events(events => events.Error("error_handler"))
.Model(model =>
{
model.Id(p => p.Id);
model.Field(p => p.Id).DefaultValue(Guid.NewGuid());
model.Field(p => p.ParentId).DefaultValue(null);
})
.Create(update => update.Action("EditingPopup_Create", "Example"))
.Read(read => read.Action("EditingPopup_Read", "Example"))
.Update(update => update.Action("EditingPopup_Update", "Example"))
.Destroy(update => update.Action("EditingPopup_Destroy", "Example"))
)
)
Here is the ExampeItem Model:
public class ExampleItem
{
[ScaffoldColumn(false)]
public Guid Id { get; set; }
public string Name { get; set; }
public string Label { get; set; }
public string Type { get; set; }
[DisplayName("Input Type")]
public string InputType { get; set; }
public ExampleItem Parent { get; set; }
public Guid ParentId { get; set; }
}
In my Controller I set the foreign key items like this:
ViewData["items"] = exampleItems; // This is a List<ExapleItem>
But for some reason the Parent column is empty when the Grid is loaded.
When I click on Edit a window pops up and shows me the Guid of the parent.
That Guid should be a drop down list of items. And the Parent column should show the name of the Parent item.
The idea of this grid is that you can add items to the grid, and when you do, you can choose any of the all ready added grid items as a parent item. Then creates an hierarchy in the Grid which can be sorted later on by the Parent.
Anyone know where I have gone wrong?

Answer 1

Not sure but as per my experience, you forgot to add editor template for the foreign key column.
As per your code you have to add default editor templates into your project.
For default editor template detail please check this for full code/demo.
You can also create your own editor template.
For ex:-
column definition for the Product
c.ForeignKey(x => x.ProductID, (List<Product>)ViewData["products"], "ID", "ProdName").EditorTemplateName("ProductIDEditor");
Here is the editor template for Product, ProductIDEditor.cshtml
#using Kendo.Mvc.UI
#(Html.Kendo().DropDownListFor(m => m)
.AutoBind(false)
.OptionLabel("Select a value...")
.DataTextField("ProdName")
.DataValueField("ID")
.DataSource(dataSource =>
{
dataSource.Read(read => read.Action("FilterProducts", "Home").Data("filterProducts"))
.ServerFiltering(true);
})
)
#Html.ValidationMessageFor(m => m)
Let me know if any concern.

Answer 2

So after trial and error I found the issue.
I changed my model to:
public class ProposalItem
{
[ScaffoldColumn(false)]
public int Id { get; set; }
public string Name { get; set; }
public string Label { get; set; }
public string Type { get; set; }
[DisplayName("Input Type")]
public string InputType { get; set; }
public ProposalItem Parent { get; set; }
[UIHint("GridForeignKey")]
public int? ParentId { get; set; }
}
So removed the Guid datatype from the Id. Also Decorated the ParentId with [UIHint("GridForeignKey")] which now gives me a DropdownList in the popup window.
It looks like there is a lack of Support for Guid's in KendoUI.
I will post another question as to why Guid's don't work.

Answer 3

Just add in :
.DataSource(source => source.Ajax()
.Model(model =>
{
model.Id(o => o.Id);
model.Field(o => o.Id).Editable(false);
model.Field(p => p.Id).DefaultValue(Guid.NewGuid());
model.Field(p => p.ParentId).DefaultValue(Guid.NewGuid());
**model.Field("ParentId", typeof(Guid));**
})
It has to do new Guid.