MVVM for Dummies I think that I have found one of the best articles on MVVM that I have ever read: This article sums up what is in MVVM and what is outside of MVVM. Note, when I and most other people say MVVM, they really mean MVVM, Commanding, Dependency Injection + any other Patterns you need to create your application. In WPF a lot of use is made of the Decorator and Behaviour pattern as well. C# – Ideal public partial class IdealView : UserControl { public IdealView() { InitializeComponent(); } } Figure: This is the ideal code behind for a Control / Window / Page when using MVVM. C# – Compromise, but works public partial class IdealView : UserControl { public IdealView() { InitializeComponent(); this.DataContext = new IdealViewModel(); } } Figure: This is a compromise, but the best you can do without Dependency Injection VB.NET – Ideal VB.NET – Compromise, but works
The MVVM Pattern Is Highly Overrated Update: check out my MVP In Silverlight/WPF series which discusses the MVP approach as an alternative to MVVM If you're doing Silverlight or WPF, you've no doubt come across the MVVM (Model-View-ViewModel) pattern. It seems to be the most popular client-side architecture pattern used among Silverlight/WPF developers. First, let's briefly cover what MVVM is about for those of you who don't know yet. The ViewModel typically contains properties for the data that is to be shown in the View, and also raises notification events when the data in those properties changes. That is, in a nutshell, how the MVVM pattern works. In most (if not all) MVVM implementations, a ViewModel has many possible reasons to be changed. Lets forget about MVVM for a second and focus on the concerns and responsibilities that a user control can have... say, a user control that shows customer information and allows the user to edit that data so it can be persisted: View: ViewModel: Presenter: Presentation Model:
Model View ViewModel MVVM facilitates a clear separation of the development of the graphical user interface (either as markup language or GUI code) from the development of the business logic or back end logic known as the model (also known as the data model to distinguish it from the view model). The view model of MVVM is a value converter[4] meaning that the view model is responsible for exposing the data objects from the model in such a way that those objects are easily managed and consumed. In this respect, the view model is more model than view, and handles most if not all of the view’s display logic (though the demarcation between what functions are handled by which layer is a subject of ongoing discussion[5] and exploration). The view model may also implement a mediator pattern organising access to the backend logic around the set of use cases supported by the view. History[edit] Microsoft MVP Josh Smith reported[6] that A notable Javascript implementation of this pattern is Knockout.js. Timeline[edit]
MVVM Explained The Open Graph Protocol MVVM Pattern Made Simple Download source - 123.66 KB Important Note Friends, I would very much appreciate if you leave me a line or two in the comments section stating how you think this article can be improved and what other topics on MVVM you want me to cover. Thanks. Introduction As many companies are switching from WinfForms to WPF/Silverlight, several project managers recently asked me almost identical questions about MVVM: What is MVVM Pattern? The purpose of this article is to answer these questions and to explain the MVVM pattern in the simplest possible way. I assume that the article readers have not had any previous exposure to the MVVM pattern but have some knowledge of WPF or Silverlight. Time permitting, I plan to write more MVVM articles which will include comparison of different MVVM frameworks and introduce a new MVVM framework. MVVM Overview Model is a set of classes representing the data coming from the services or the database. WPF Bindings These properties serve as the source properties.
Patron de conception Un article de Wikipédia, l'encyclopédie libre. Pour les articles homonymes, voir Patron. En informatique, et plus particulièrement en développement logiciel, un patron de conception (en anglais : design pattern) est un arrangement caractéristique de modules, reconnu comme bonne pratique en réponse à un problème de conception d'un logiciel. Il décrit une solution standard, utilisable dans la conception de différents logiciels[1]. Les patrons de conception décrivent des procédés de conception généraux et permettent en conséquence de capitaliser l'expérience appliquée à la conception de logiciel. Les types de patrons[modifier | modifier le code] Les patrons de conception ne sont ni des patrons d'architecture ni des idiotismes de programmation. Description[modifier | modifier le code] Les patrons servent à documenter des bonnes pratiques basées sur l'expérience. Histoire[modifier | modifier le code] Citations[modifier | modifier le code] Formalisme[modifier | modifier le code] Adapter Bridge Builder
THE MODEL-VIEW-VIEWMODEL (MVVM) DESIGN PATTERN FOR WPF Patterns WPF Apps With The Model-View-ViewModel Design Pattern Josh Smith Developing the user interface of a professional software application is not easy. It can be a murky blend of data, interaction design, visual design, connectivity, multithreading, security, internationalization, validation, unit testing, and a touch of voodoo. There are popular design patterns that can help to tame this unwieldy beast, but properly separating and addressing the multitude of concerns can be difficult. It is not always the design patterns at fault. As the software world continues to adopt WPF at an increasing rate, the WPF community has been developing its own ecosystem of patterns and practices. By the end of this article, it will be clear how data templates, commands, data binding, the resource system, and the MVVM pattern all fit together to create a simple, testable, robust framework on which any WPF application can thrive. Order vs. The Evolution of Model-View-ViewModel The Demo Application
Binding Un article de Wikipédia, l'encyclopédie libre. Un binding ou liaison (qui est un terme anglais désignant l'action de lier des éléments entre eux) peut avoir plusieurs significations en informatique : Binding de langage[modifier | modifier le code] Nombre de bibliothèques sont écrites dans des langages proches de la machine comme le C ou le C++. Pour utiliser ces bibliothèques dans un langage de plus haut niveau, il est donc nécessaire de réaliser un binding. La conception d'un binding peut être motivée par le fait de profiter des performances offertes par l'utilisation d'un langage bas niveau que l'on ne peut obtenir avec un langage de plus haut niveau. XML data binding[modifier | modifier le code] Le fait de représenter un document XML sous forme d'objet simplifie sa manipulation lors du développement d'un logiciel. Data binding[modifier | modifier le code]
MVVM Compared To MVC and MVP Saturday, November 21, 2009 6:53 PM At the recent Calgary Tech Days event I did a presentation on building composite applications with WPF and Silverlight. One question that I get asked frequently when I get to the part of explaining MVVM is how its different from patterns that seem too similar or identical, with MVC and MVP typically being the two common ones raised. Usually my answer is that MVVM is very similar to the others, but it implies *stuff* that’s specific to Silverlight and WPF (how binding works, commanding, etc.). So below I have a comparison, pointing out the key differences between the patterns and why MVVM *is* different. MVC – Model View Controller Let’s look at MVC first. The input is directed at the Controller first, not the view. There is a many-to-one relationship between the Controller and the View. Note the one way arrow from Controller to View. MVP – Model View Presenter Now let’s look at the MVP pattern. The input begins with the View, not the Presenter. Conclusion
MVVM Light Toolkit Introduction The main purpose of the toolkit is to accelerate the creation and development of MVVM applications in WPF, Silverlight, Windows Store (RT) and for Windows Phone. The MVVM Light Toolkit helps you to separate your View from your Model which creates applications that are cleaner and easier to maintain and extend. It also creates testable applications and allows you to have a much thinner user interface layer (which is more difficult to test automatically). This toolkit puts a special emphasis on the "blendability" of the created application (i.e. the ability to open and edit the user interface into Blend), including the creation of design-time data to enable the Blend users to "see something" when they work with data controls. Documentation There is documentation about the MVVM pattern and the MVVM Light Toolkit available here. Installation and Creation The MVVM Light Toolkit installation procedure (for the full package) is described here. Source code and Codeplex Support Donate