Nuno Filipe Godinho

PDC09 – Day Two – Advanced Topics for Building Large-Scale Applications with Microsoft Silverlight

MVVM – Model-View-ViewModel

• Separation of concerns
• View = handled UI
• Model = contains pure data
• ViewModel = communicates between View and Model through bindings
• Works Great with Silverlight and WPF
• XAML based data bindings
• Testable

• Model
• Represents the Data
• The entity
• Not required to know where it gets the data from
• WCF service, WCF Ria Services
• View
• The Screen, the UI
• ViewModel
• Main source of logic for the MVVM triad
• Connects the Model and the View
• Abstracts the View
• Public Properties that are bound to the View
• INotifyPropertyChanged and INotifyCollectionChanged talk to the view through bindings
• Listens for changes from the View made to the Model
• Variations of the MVVM
• View First
• ViewModel is declared as StaticResource in the Views XAML
• Works well in Blend
• Another way is to create the ViewModel in the View’s code-behind
• ViewModel First
• View is injected into the ViewModel’s constructor
• Doesn’t allow the possibility to use Blend
• View and ViewModel Marriage
• View must be paired with the ViewModel somehow
• Doesn’t allow the possibility to use Blend
• What don’t we have with MVVM
• Commanding

Prism 2

• Prism is a set of options
• Use what you want and ignore the rest
• Technical Concepts:
• Modules
• Shell
• Commands
• Containers
• Regions
• Bootstrapper
• Event Aggregation
• Unity and Dependency Injection