Language filtered Multilist field

Recently I happened to help one of our clients to create a custom Multilist field that gives you selecting options only if item has  at least one translated version in a current content language. From content author’s point of view it makes a lot of sense. Why to give them an option that is not useful?

It’s being a while since I created a custom field that has to take into account content language selection. The main challenge for me was to retrieve that content language. I did remember that there is a property that the Content Editor (CE) sets at run-time for every field but could not recall its name. So after several minutes of browsing my code storage of all samples for all Sitecore versions, I finally found it. So, here are the properties that you need to define in your custom field if you are planning to use them afterwards:

- ItemLanauage – represents a content language selected in the CE.

- ItemID – contains the item ID the field belongs to.

- ItemVersion – contains selected item version.

- ReadOnly – indicates if field is a readonly. If it is, then it will be grayed out and not editable.

- Source – represents the source value from field definition on a data template.

- FieldID – contains the field ID.

In my example I needed only ItemLanguage property. When I put things together the code looked like this:

using Sitecore.Shell.Applications.ContentEditor;
using Sitecore.Data.Items;

namespace Sitecore.Shell.Applications.ContentEditor.CustomExtensions
{
    public class LanguageFilteredMultilist : Sitecore.Shell.Applications.ContentEditor.MultilistEx
    {
        #region Overrides

        protected override Item[] GetItems(Item current)
        {              
            Item[] items = base.GetItems(current);

            var filteredItems = items.Where(item => 
                    {
                        string lang = ItemLanguage;
                        if (!string.IsNullOrEmpty(lang))
                        {
                            var versions = Sitecore.Data.Managers.ItemManager.GetVersions(item, Sitecore.Data.Managers.LanguageManager.GetLanguage(lang, item.Database));
                            return versions.Count > 0;
                        }
                        return false;
                    }
                );   
            
            return filteredItems.ToArray<Item>();
        }

        #endregion Overrides

        // Content Editor sets this property. It has a content language from the Content Editor.
        public string ItemLanguage
        {
            get;
            set;
        }
    }
}

Simple enough isn’t it. Don’t forget to add your custom field to /App_Config/FieldTypes.config file if it’s supposed to contain references to other items. In my case it should be added since it’s a multilist. If you forget to do it, the LinkDatabase won’t update references for your field.

That’s all for now.

Cross Database TreeList Field

Sometimes we would like to have an opportunity to get data from another database in sitecore field. Since we already have source code of TreeList field on SDN, I decided to adjust it a little bit to have such opportunity.
To allow cross db usage I had to add one parameter to the source query of TreeList field.
It's SourceDatabaseName parameter.
Here is example how to get users from security database in TreeList field.

DataSource=/sitecore/users&SourceDatabaseName=security

Here is the way it looks:


To get rid of broken links in this field I had to MultilistCrossDbField which is intended to validate links correctly in LinkDatabase. So, don't forget to add the line below into /App_Config/FieldTypes.config file:

<configuration>
............
<!-- Custom fields -->
<fieldtype name="tree list cross db" type="Custom.Data.Fields.MultilistCrossDbField,TreeListCrossDB">
</fieldtype>
</configuration>

I added support for "query:" definition into this field. Now you can use either "/sitecore/content" or "query:/sitecore/content/*" as a data source for the field.

Here is Sitecore Package for the field.
Here is source code.