mvvm-toolkit-messenger
CommunityToolkit.Mvvm Messenger pub/sub for decoupled communication between ViewModels (or any objects). Covers WeakReferenceMessenger vs StrongReferenceMessenger, IRecipient<TMessage>, RequestMessage<T> / AsyncRequestMessage<T> / CollectionRequestMessage<T>, ValueChangedMessage<T>, channels (tokens), and the ObservableRecipient activation lifecycle. Use across WPF, WinUI 3, .NET MAUI, Uno, and Avalonia.
Profile →npx skills add github/awesome-copilot --skill mvvm-toolkit-messenger --agent copilot
Same command for any agent — swap --agent for claude-code, codex, cursor.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# CommunityToolkit.Mvvm Messenger Pub/sub messaging for ViewModels (or any objects) without forcing a shared reference graph. Part of `CommunityToolkit.Mvvm` 8.x. > **TL;DR.** Default to `WeakReferenceMessenger.Default`. Register handlers > with the `(recipient, message)` lambda and the `static` modifier so you > never capture `this`. Inherit from `ObservableRecipient` and toggle > `IsActive` at activation/deactivation to get automatic register/unregister. --- ## When to use this skill - Two or more ViewModels need to react to an event (login, theme change, save, navigation) without holding references to each other - A ViewModel needs to ask another VM for a value (request/reply) - You're scoping events to a sub-system or window with channel tokens - Diagnosing "my handler never fires" or weak-reference recipient lifetime problems For source generators, base classes, and commands see the **`mvvm-toolkit`** skill. For DI wiring (registering an `IMessenger` instance), see **`mvvm-toolkit-di`**. --- ## Choose an implementation | Type | When | |------|------| | `WeakReferenceMessenger.Default` | **Default.** Recipients held weakly — eligible for GC even while registered. Internal trimm
- When to use this skill
- Choose an implementation
- Define a message
- Register a recipient
- Lambda style (recommended)
- IRecipient<TMessage> interface style
- Send a message
- Channels (tokens)
- Request / reply
- Sync request
- Async request
- Collection requests (fan-in)
- Lifecycle
- Common pitfalls
What does the mvvm-toolkit-messenger skill do?
CommunityToolkit.Mvvm Messenger pub/sub for decoupled communication between ViewModels (or any objects). Covers WeakReferenceMessenger vs StrongReferenceMessenger, IRecipient<TMessage>, RequestMessage<T> / AsyncRequestMessage<T> / CollectionRequestMessage<T>, ValueChangedMessage<T>, channels (tokens), and the ObservableRecipient activation lifecycle. Use across WPF, WinUI 3, .NET MAUI, Uno, and Avalonia.
How do I install it?
Run `npx skills add github/awesome-copilot --skill mvvm-toolkit-messenger --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From github/awesome-copilot, a repository with 37,432 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.