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Datalist returns null from block settings

See original GitHub issue

What is the current behaviour?

We have a custom data source to select some devices / screen resolutions to hide some block elements, where we use some block settings.

public class DeviceDataSource : IDataListSource, IDataListSourceValueConverter
    private readonly Dictionary<string, DeviceType> _lookup;

    public DeviceDataSource()
        var devices = new List<DeviceType>
            new DeviceType {
                Name = "Mobile",
                Key = "mobile",
                Icon = "icon-iphone",
            new DeviceType {
                Name = "Tablet",
                Key = "tablet",
                Icon = "icon-ipad",
            new DeviceType {
                Name = "Desktop",
                Key = "desktop",
                Icon = "icon-display",
        _lookup = devices.ToDictionary(x => x.Key.ToString());

    public string Name => "Devices";

    public string Description => "Data source for devices.";

    public string Icon => "icon-brick";

    public OverlaySize OverlaySize => OverlaySize.Small;

    public Dictionary<string, object> DefaultValues => default;

    public IEnumerable<ConfigurationField> Fields => default;

    public IEnumerable<DataListItem> GetItems(Dictionary<string, object> config)
        return _lookup
            .Select(x => new DataListItem
                Name = x.Value.Name,
                Value = x.Key,
                Icon = x.Value.Icon,
                Description = ""

    public Type GetValueType(Dictionary<string, object> config) => typeof(DeviceType);

    public object ConvertValue(Type type, string value) => _lookup.ContainsKey(value) == true ? _lookup[value] : null;

public class DeviceType
    public string Name { get; set; }
    public string Key { get; set; }
    public string Icon { get; set; }

In this use-case the content types also vary by culture, but not the element types or block settings.

This works fine when using the property directly on a Settings node (which vary by culture). However if accessing the property from a Settings element type on a block element placed in Block List on a Standard Page (which vary by culture) the property returns null instead of the selected items.

What is the expected behaviour?

The property on either block content or block settings to return the selected items.

Please tell us about your set-up:

  • Contentment version: [1.4.2]
  • Umbraco version: [8.9.0]
  • Umbraco ModelsBuilder is: [enabled]
  • Browser: [all]

Anything else?

Settings node


Block element settings


Block element


Issue Analytics

  • State:closed
  • Created 2 years ago
  • Comments:12 (5 by maintainers)

github_iconTop GitHub Comments

leekellehercommented, May 25, 2021

@bjarnef FYI, released v1.4.3.

bjarnefcommented, Oct 25, 2021

@leekelleher oh, that is beautiful, just what I need 😎 Combined with custom SVG icons that’s a pretty cool feature. #h5yr 🙌👏

public enum Alignment
    [DataListItem(Icon = "align-left")]
    [EnumMember(Value = "left")]

    [DataListItem(Icon = "align-center")]
    [EnumMember(Value = "center")]

    [DataListItem(Icon = "align-right")]
    [EnumMember(Value = "right")]


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