uno-mvux-listfeed

name	uno-mvux-listfeed
description	Create and use IListFeed<T> for reactive collections in MVUX.
when_to_use	Use when loading a list of items from a service or API, displaying collections in `ListView`, `GridView`, or `ItemsRepeater`, filtering list data reactively, or choosing between `IListFeed<T>` (read-only) and `IListState<T>` (mutable).
metadata	{"author":"uno-platform","version":"2.3","category":"mvux"}

MVUX ListFeed — Agent Skill

Workflow

Docs lookup: call uno_platform_docs_search(...) first, then uno_platform_docs_fetch(sourcePath="…") using the sourcePath field from a result (a relative .md path; add the result's anchor for a section). Never pass a URL, a .html link, or a hand-built path.

Step 1: Fetch the ListFeed Reference Documentation

Search for and fetch the documentation:

uno_platform_docs_search("MVUX ListFeed reactive collection IListFeed")

Primary documentation pages:

• ListFeed Reference: external/uno.extensions/doc/Reference/Reactive/listfeed.md
• ListFeed How-To: external/uno.extensions/doc/Learn/Mvux/Walkthrough/ListFeed.howto.md

Fetch the full reference:

uno_platform_docs_fetch(sourcePath="external/uno.extensions/doc/Reference/Reactive/listfeed.md")

Step 2: Learn ListFeed Creation Methods

From the fetched docs, the key factory methods on the ListFeed static class:

• ListFeed.Async(...) — from a method returning Task<IImmutableList<T>>
• ListFeed.AsyncEnumerable(...) — from an IAsyncEnumerable<IImmutableList<T>>
• ListFeed.PaginatedAsync(...) — for paginated/infinite scroll (see uno-mvux-pagination skill)

Step 3: For ListFeed Operators

The reference page covers operators like Where, Select, and AsFeed. These operate on individual items in the collection.

Step 4: For How-To Walkthroughs

For step-by-step examples:

uno_platform_docs_fetch(sourcePath="external/uno.extensions/doc/Learn/Mvux/Walkthrough/ListFeed.howto.md")

This covers loading a list, showing it with FeedView, filtering with Where, and when to use feeds vs states.

Step 5: For Displaying Lists in XAML

The how-to page shows how to bind IListFeed<T> to ListView via FeedView and access items through {Binding Data}.

Key Principles (Stable)

• IListFeed<T> is read-only — use IListState<T> for add/remove/update
• Service methods should return ValueTask<IImmutableList<T>> (from System.Collections.Immutable)
• Operators like Where and Select work on individual items, not the list itself
• ListFeed automatically handles loading/error/empty states
• Use IListFeed<T> when data is pulled from a service and is read-only
• Use IListState<T> when you need to edit the collection client-side

Key Equality Requirement (Critical)

All item types used in IListFeed<T> MUST support key equality via Uno.Extensions.Equality.IKeyEquatable<T>. Without key equality, MVUX cannot distinguish between a modified entity and a completely different one, causing full list re-renders instead of granular item updates (flickering, lost scroll position, broken animations).

Automatic generation (recommended)

For partial record types, key equality is auto-generated when the record has a property named Id or Key:

public partial record Person(Guid Id, string Name, int Age);
// IKeyEquatable<Person> is generated automatically — Id is the key

Explicit key configuration

Use [Key] attribute when the key property has a different name, or for composite keys:

public partial record OrderLine(
    [property: Key] Guid OrderId,
    [property: Key] int LineNumber,
    string Product,
    decimal Price);

Either Uno.Extensions.Equality.KeyAttribute or System.ComponentModel.DataAnnotations.KeyAttribute can be used.

Assembly-level defaults

Configure which property names are auto-detected as keys:

[assembly: ImplicitKeyEquality("Id", "Key", "EntityId")]

Disabling generation

If auto-generation causes issues on a specific type:

[ImplicitKeys(IsEnabled = false)]
public partial record MyItem(Guid Id, string Name);

Rules

• The item type must be a partial record (or manually implement IKeyEquatable<T>)
• At least one key property is required — without it, every update replaces the entire list in the UI
• Key properties define identity (same entity); non-key properties define state (changed data)
• KeyEquals returns true when two instances represent the same entity, even if other properties differ

Related Skills

• [[uno-mvux-feed-basics]] — Single-value feeds
• [[uno-mvux-liststate]] — Mutable reactive collections
• [[uno-mvux-selection]] — Selection management with list feeds
• [[uno-mvux-pagination]] — Infinite scroll / paginated lists
• [[uno-mvux-feedview]] — Displaying feed data in XAML