Silverlight 3 LoadedEvent routed to ViewModel

Question

My client is trying to hook to a usercontrols Loaded Event in the View Model. Basically they want to know when the controls loaded event triggers inside the view model. They are looking for a way to do it without code behind the xaml. Is this even feasible. I am looking into whether I can route the loaded event to the viewmodel in the xaml.

Answer 1

You need to look into commanding. Silverlight support is fairly weak compared to WPF but it does contain the ICommand interface. You can extend controls to give them command properties or implement them via an attached property. The commands basically invoke themselves once an action has occurred in the UI. They are totally independent of how the UI is built (or at least they should be) and so can be completely unit tested.

Answer 2

One way of doing it is to use InvokeDataCommand. You'd specify the trigger's EventName as Loaded, and then your command (defined in your VM) would execute when Loaded event is fired.