uno-mvux-commands

name	uno-mvux-commands
description	Create and use commands in MVUX for user interactions.
when_to_use	Use when binding a Button (or other control) to a method on the Model, understanding how methods become commands in the generated ViewModel, passing feed/state values as parameters to commands, controlling which methods generate commands (implicit vs explicit), or disabling command generation for specific methods.
metadata	{"author":"uno-platform","version":"2.4","category":"mvux"}

MVUX Commands — 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 Commands Documentation

Search for and fetch the commands documentation:

uno_platform_docs_search("MVUX commands automatic generation method invocation")

Primary documentation pages:

• Commands Reference: external/uno.extensions/doc/Learn/Mvux/Advanced/Commands.md
• Commands How-To: external/uno.extensions/doc/Learn/Mvux/Walkthrough/Commands.howto.md

Fetch the reference page for complete details:

uno_platform_docs_fetch(sourcePath="external/uno.extensions/doc/Learn/Mvux/Advanced/Commands.md")

Step 2: Understand Implicit Command Generation

From the fetched docs, any public method on a Model automatically becomes a command in the generated ViewModel. The reference page covers:

• Basic command generation rules
• Using CommandParameter from XAML
• Additional feed parameters (method parameter names matching feed property names)
• The [ImplicitCommands] attribute to enable/disable generation

Step 3: For How-To Walkthroughs

For step-by-step examples:

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

This covers creating basic commands, using feed values in commands, can-execute logic, and disabling command generation.

Step 4: For Explicit Command Creation

If the user needs manual control over commands, the reference page has an "Explicit command creation" section covering Command.Create(...).

Critical Rules

• Feed parameter injection works for any feed type (IFeed<T>, IListFeed<T>, IState<T>, IListState<T>) — the matching parameter receives a snapshot of the current value.
• But you can only mutate writable types from inside a command body. IState<T> and IListState<T> expose UpdateAsync / AddAsync / RemoveAsync. IFeed<T> and IListFeed<T> are read-only — calling .Update(...), .UpdateAsync(...), .AddAsync(...), or .RemoveAsync(...) on an injected IListFeed/IFeed is a compile error.
• If a command needs to mutate a collection, the property on the Model must be IListState<T> (not IListFeed<T>); convert with ListState.FromFeed(this, sourceFeed) if needed.
• When mutating via UpdateAsync, the updater must be pure — derive the new value solely from the current value, with no captured external state or side effects. See [[uno-mvux-state-basics]] and [[uno-mvux-liststate]] for details.

Key Principles (Stable)

• Any public method on a *Model partial record generates a command in the ViewModel
• Commands are automatically IAsyncCommand — they handle async properly
• Feed parameter injection: a method parameter whose name/type matches a Feed property gets the current feed value injected
• Use [ImplicitCommands(false)] on a Model to disable automatic generation
• Commands are bound in XAML via Command="{Binding MethodName}"
• The method name becomes the command name (e.g., Save() → Save command)

Related Skills

• [[uno-mvux-state-basics]] — States that commands often update
• [[uno-mvux-feed-basics]] — Feeds whose values commands can consume
• [[uno-mvux-selection]] — Selection-aware commands