ICollectionView

[CBl...@eki-consulting.com]

As some of you may know, I really like using CollectionViews in my
ViewModels. I even got Laurent to use PagedCollectionView in the WCF RIA
Services section of his new book.

Recently however, I became aware of the memory leak inherent in their
design. Every ICollectionView implementation I know of subscribes to the
OnCollectionChanged event of the source collection with no way to force the
ICollectionView to unsubscribe. In my current ViewModels, this is not a
problem as my PagedCollectionViews live as long as their source collections
anyway so this hasn't been a problem. However, in an application where the
source collections have a longer lifetime than the ViewModels that create
the CollectionViews I could forsee this becoming a massive memory leak
problem.

I am wondering what the correct solution would be. Should CollectionViews
all implement IDisposable as well?

[Peter O'Hanlon]

I prefer the idea of WeakCollectionViews. Weak references are a much better idea to my mind.

--
Peter O'Hanlon

[Sacha Barber]

I say use weak event everywhere you can, there are so many nasty gotchas out there. We had one the other day, when someone has a an attached behaviour where they were binding to a ICommand.CanExecuteChanged in DP. 

Bad memory leak right there, and it was used a lot.

WeakEvent proxy to the rescue

--
Sacha Barber
sacha....@gmail.com