Sitecore MVC - Controller Renderings - View Model for Custom Item

Question

How do I bind a Custom Item generated with "Custom Item Generator" to my view model for a controller rendering? There is a data source that is returning a list of the Custom Items. Also, one of the custom items is an image. It sounds like I should be using Glass Mapper, but it's not clear to me what it does and how that relates to what I am trying to do. This code does not build.

View:

@using Sitecore.Mvc.Presentation
@using Sitecore.Mvc
@model MyCompanyBootstrap.CustomItems.RotatorContentItem

@foreach (var item in Model.RotatorItems)
{
    <h2>@item.Fields["Title"]</h2>
    @item.Fields["Sub Title"]
}
@Model.Title
<br />
@Model.Text

Controller Action:

public ActionResult Index()
{
    var dataSourceId = RenderingContext.CurrentOrNull.Rendering.DataSource;
    var dataSource = Sitecore.Context.Database.GetItem(dataSourceId);
    var viewModel = new RotatorContentItem();
    viewModel.RotatorItems = dataSource.Children;
    viewModel.Initialize(RenderingContext.Current.Rendering);
    return View(viewModel);
}

Custom Item:

public partial class RotatorContentItem : CustomItem
{

public static readonly string TemplateId = "{E493DF4A-E97E-49B5-BF9F-F70397EA8D21}";


#region Boilerplate CustomItem Code

public RotatorContentItem(Item innerItem) : base(innerItem)
{

}

public static implicit operator RotatorContentItem(Item innerItem)
{
    return innerItem != null ? new RotatorContentItem(innerItem) : null;
}

public static implicit operator Item(RotatorContentItem customItem)
{
    return customItem != null ? customItem.InnerItem : null;
}

#endregion //Boilerplate CustomItem Code


#region Field Instance Methods


public CustomTextField Title
{
    get
    {
        return new CustomTextField(InnerItem, InnerItem.Fields["Title"]);
    }
}


public CustomTextField SubTitle
{
    get
    {
        return new CustomTextField(InnerItem, InnerItem.Fields["Sub Title"]);
    }
}


public CustomImageField ImageLarge
{
    get
    {
        return new CustomImageField(InnerItem, InnerItem.Fields["Image Large"]);
    }
}


public CustomImageField ImageSmall
{
    get
    {
        return new CustomImageField(InnerItem, InnerItem.Fields["Image Small"]);
    }
}


public CustomGeneralLinkField Link
{
    get
    {
        return new CustomGeneralLinkField(InnerItem, InnerItem.Fields["Link"]);
    }
}


public CustomCheckboxField IsOverlayBlack
{
    get
    {
        return new CustomCheckboxField(InnerItem, InnerItem.Fields["Is Overlay Black"]);
    }
}


#endregion //Field Instance Methods
}

Edit: There are a number of things wrong with this code that I am seeing now. I think there should be a new class specifically for the View Model itself. And that class should have a list of RotatorContentItems.

public List<RotatorContentItem> RotatorContentItems { get; set; }

But, it is not clear to me how to bind that list in the controller action.

public class MyViewModel
{
    public List<RotatorContentItem> RotatorContentItems { get; set; }
    public IEnumerable<Item> RotatorItems { get; set; }
}

public ActionResult Index()
{
    var dataSourceId = RenderingContext.CurrentOrNull.Rendering.DataSource;
    var dataSource = Sitecore.Context.Database.GetItem(dataSourceId);
    var viewModel = new MyViewModel();
    viewModel.RotatorContentItems = dataSource.Children;
    viewModel.RotatorItems = dataSource.Children;
    return View(viewModel);
}

This will not build on the following line:

viewModel.RotatorContentItems = dataSource.Children;

Error is:

Cannot implicitly convert type 'Sitecore.Collections.ChildList' to 'System.Collections.Generic.List<MyCompnayBootstrap.CustomItems.RotatorContentItem>'

Answer 1

The problem is that on MyViewModel your RotatorContentItems are of type List<RotatorContentItem>, but dataSource.Children is of type Sitecore.Collections.ChildList.

View Model:

public class MyViewModel
{
    public List<RotatorContentItem> RotatorContentItems { get; set; }
}

You're not using RotatorItems at all so no need to add that property to MyViewModel.

Controller Action:

public ActionResult Index()
{
    var dataSourceId = RenderingContext.CurrentOrNull.Rendering.DataSource;
    var dataSource = Sitecore.Context.Database.GetItem(dataSourceId);

    var viewModel = new MyViewModel
    {
        RotatorContentItems = dataSource.Children.Select(c => new RotatorContentItem(c)).ToList()
    };

    return View(viewModel);
}

View:

@using Sitecore.Mvc.Presentation
@using Sitecore.Mvc
@model MyViewModel

@foreach (var item in Model.RotatorContentItems)
{
    <h2>@item.Title.Text</h2>
    @item.SubTitle.Text
}

Answer 2

I believe your problem is when you're instantiating the custom item. You want to pass an Item to the CustomItem constructor in order to use the properties.

Try this:

public ActionResult Index()
{
    var dataSourceId = RenderingContext.CurrentOrNull.Rendering.DataSource;
    var dataSource = Sitecore.Context.Database.GetItem(dataSourceId);
    var viewModel = new RotatorContentItem(datasource);
    viewModel.RotatorItems = dataSource.Children;
    viewModel.Initialize(RenderingContext.Current.Rendering);
    return View(viewModel);
}

This code will be repeated in every controller you create, so it is worth abstracting it to a base class that your controllers would inherit from, and you can pass the CustomItem type as a type argument. You can do something like this,

public abstract class BaseCustomItemController<T> : where T is CustomItem
{
  public virtual ActionResult Index()
  {
    var dataSourceId = RenderingContext.CurrentOrNull.Rendering.DataSource;
    T viewModel = Sitecore.Context.Database.GetItem(dataSourceId);
    return View(viewModel);
  }
}

Glass.Mapper is worth learning and probably a better choice for working with MVC. You can use the GlassViewModel class it ships with and skip controllers altogether and just use View Renderings.