MVVM Light: how to unregister Messenger

Question

I love the MVVM Light\'s Messenger and its flexibility, however I\'m experiencing memory leaks when I forget to explicitly unregister the recipients (in Silverlight 4).

Answer 1

The ViewModelLocator class helps keep a centralized store for your viewmodels. You can use this class to help manage new versions and clean up old ones. I always reference my viewmodel from view via the locator, so I always have code I can run to manage these things. You could try that.

As well, I use the Cleanup method to call Messenger.Unregister(this), which cleans up all references from the messenger for that object. You have to call .Cleanup() every time, but such is life :)

Answer 2

I've not used MVVM Light (though I've heard great things), but if you want a Messenger implementation that uses WeakReferences, checkout the Messenger included here http://mvvmfoundation.codeplex.com/.

Answer 3

MVVM Light Messenger is using WeakAction(WeakReference). So you don't need to Unregister explicitly.