Question

hi what is the easiest way to implement asynch operations on WPF and MVVM, lets say if user if user hits enter when on a field i want to launch a command and then return back while a thread will do some search operations and then come back and update the properties so notification can update the bindings.

thanks!

Answer 1

How about a BackgroundWorker instance to call your command on the VM ?

Update:
Scratch the above suggestion.. There’s an online video on MVVM by Jason Dolinger.. I recommend you take a look at that. It’s a cleaner way where the view is thin/ does not hold any threading code.

To summarize:

• the VM ctor caches the Dispatcher.CurrentDispatcher object (main thread).
• when updating the backing store (results), use
  _dispatcher.BeginInvoke( () => _results.AddRange( entries) ) so that the UI is updated correctly.