In Sitecore SXA already exist a Reference rendering variant which lets you display fields from a referenced item.
For the reference rendering variant If you want to display a field from a referenced item, you can define this field in the “Pass through field” field.
To display fields from referrers items we need to create a custom Referrer Rendering Variant.
First thing we need to create a template for Referrers Rendering Variant which should inherit from “_Rendering Variants Base” and “_Variant Paging”
We need to create the model for this template.
public class VariantReferrers : BaseVariantField
{
public int? MaxNumberOfResults { get; set; }
public int? NumberOfResultsToSkip { get; set; }
public IEnumerable<BaseVariantField> Items { get; set; }
public string RefferItemTemplateName { get; set; }
}
To create the VariatReferrers model we need to create it inside a class which inherits from ParseVariantFieldProcessor and to render it we need to create a class which interits from RenderRenderingVariantFieldProcessor
public class ParseReferrers : ParseVariantFieldProcessor
{
public override ID SupportedTemplateId => Templates.VariantReferrers.ID;
public override void TranslateField(ParseVariantFieldArgs args)
{
var obj = new VariantReferrers
{
ItemName = args.VariantItem.Name,
RefferItemTemplateName = args.VariantItem[Templates.VariantReferrers.Fields.TemplatesAllowed]
};
IList<BaseVariantField> items;
if (args.VariantItem.Children.Count <= 0)
{
IList<BaseVariantField> list = new List<BaseVariantField>();
items = list;
}
else
{
items = ServiceLocator.ServiceProvider.GetService<IVariantFieldParser>()
.ParseVariantFields(args.VariantItem, args.VariantRootItem, false);
}
obj.Items = items;
args.TranslatedField = obj;
if (int.TryParse(args.VariantItem[Sitecore.XA.Foundation.RenderingVariants.Templates._VariantPaging.Fields.MaxNumberOfResults], out var result))
(args.TranslatedField as VariantReferrers).MaxNumberOfResults = result;
if (int.TryParse(args.VariantItem[Sitecore.XA.Foundation.RenderingVariants.Templates._VariantPaging.Fields.NumberOfResultsToSkip], out var result2))
(args.TranslatedField as VariantReferrers).NumberOfResultsToSkip = result2;
}
}
SupportedTemplateId propery represents the ID of the template created above.
Inside TranslatedField method we set the RefferItemTemplateName property with the value from rendering variant.
On RenderReferrers class , inside method RenderField is the logic to get the referrers of current item and we filter refferes item by templatename.
public class RenderReferrers : RenderVariantFieldProcessor
{
public override Type SupportedType => typeof(VariantReferrers);
public override RendererMode RendererMode => RendererMode.Html;
public override void RenderField(RenderVariantFieldArgs args)
{
VariantReferrers variantReferrers = args.VariantField as VariantReferrers;
if (string.IsNullOrWhiteSpace(variantReferrers?.RefferItemTemplateName) || !variantReferrers.Items.Any())
{
return;
}
List<Item> targetItems = GetReffererItems(args, variantReferrers);
if (!targetItems.Any())
{
return;
}
Control control = new PlaceHolder();
foreach (Item item in targetItems)
{
foreach (BaseVariantField referencedItem in variantReferrers.Items)
{
RenderVariantFieldArgs renderVariantFieldArgs = new RenderVariantFieldArgs
{
VariantField = referencedItem,
Item = item,
HtmlHelper = args.HtmlHelper,
IsControlEditable = args.IsControlEditable,
IsFromComposite = args.IsFromComposite,
RendererMode = args.RendererMode,
Model = args.Model
};
base.PipelineManager.Run("renderVariantField", renderVariantFieldArgs);
if (renderVariantFieldArgs.ResultControl != null)
{
control.Controls.Add(renderVariantFieldArgs.ResultControl);
}
}
}
args.ResultControl = control;
args.Result = RenderControl(args.ResultControl);
}
protected List<Item> GetReffererItems(
RenderVariantFieldArgs args,
VariantReferrers variantReferrers)
{
var currentItem = args.Item;
var links= Globals.LinkDatabase.GetReferrers(currentItem);
var originalSource = links.Select(i => i.GetSourceItem()).Where(i => i != null&& i.TemplateName.Equals(variantReferrers.RefferItemTemplateName));
if (variantReferrers.NumberOfResultsToSkip.HasValue)
originalSource = originalSource.Skip<Item>(variantReferrers.NumberOfResultsToSkip.Value);
int? maxNumberOfResults = variantReferrers.MaxNumberOfResults;
if (maxNumberOfResults.HasValue)
{
IEnumerable<Item> source2 = originalSource;
maxNumberOfResults = variantReferrers.MaxNumberOfResults;
int count = maxNumberOfResults.Value;
originalSource = source2.Take<Item>(count);
}
return originalSource.ToList<Item>();
}
}
We need to register these 2 processors in a config file:
<?xml version="1.0"?>
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/" xmlns:role="http://www.sitecore.net/xmlconfig/role/">
<sitecore>
<pipelines>
<parseVariantFields>
<processor type="XA.Reference.Foundation.RenderingVariants.Pipelines.ParseVariantFields.ParseReferrers, XA.Reference.Foundation.RenderingVariants" />
</parseVariantFields>
<renderVariantField>
<processor type="XA.Reference.Foundation.RenderingVariants.Pipelines.ParseVariantFields.RenderReferrers, XA.Reference.Foundation.RenderingVariants" />
</renderVariantField>
</pipelines>
</sitecore>
</configuration>
