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PODoes this MSDN article violate MVVM?
 

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    <p>This may be old news but back in March 2009, this article, “<a href="http://msdn.microsoft.com/en-us/magazine/dd458800.aspx" rel="nofollow noreferrer">Model-View-ViewModel In Silverlight 2 Apps</a>,” has a code sample that includes <code>DataServiceEntityBase</code>:</p> <pre><code>// COPIED FROM SILVERLIGHTCONTRIB Project for simplicity /// &lt;summary&gt; /// Base class for DataService Data Contract classes to implement /// base functionality that is needed like INotifyPropertyChanged. /// Add the base class in the partial class to add the implementation. /// &lt;/summary&gt; public abstract class DataServiceEntityBase : INotifyPropertyChanged { /// &lt;summary&gt; /// The handler for the registrants of the interface's event /// &lt;/summary&gt; PropertyChangedEventHandler _propertyChangedHandler; /// &lt;summary&gt; /// Allow inheritors to fire the event more simply. /// &lt;/summary&gt; /// &lt;param name="propertyName"&gt;&lt;/param&gt; protected void FirePropertyChanged(string propertyName) { if (_propertyChangedHandler != null) { _propertyChangedHandler(this, new PropertyChangedEventArgs(propertyName)); } } #region INotifyPropertyChanged Members /// &lt;summary&gt; /// The interface used to notify changes on the entity. /// &lt;/summary&gt; event PropertyChangedEventHandler INotifyPropertyChanged.PropertyChanged { add { _propertyChangedHandler += value; } remove { _propertyChangedHandler -= value; } } #endregion </code></pre> <p>What this class implies is that the developer <em>intends</em> to bind visuals <em>directly</em> to data (yes, a ViewModel is used but it defines an <code>ObservableCollection</code> of data objects). Is this design diverging too far from the guidance of MVVM? Now I can see some of the reasons Why would we go this way: what we can do with <code>DataServiceEntityBase</code> is this sort of thing (which is intimate with the Entity Framework):</p> <pre><code>// Partial Method to support the INotifyPropertyChanged interface public partial class Game : DataServiceEntityBase { #region Partial Method INotifyPropertyChanged Implementation // Override the Changed partial methods to implement the // INotifyPropertyChanged interface // This helps with the Model implementation to be a mostly // DataBound implementation partial void OnDeveloperChanged() { base.FirePropertyChanged("Developer"); } partial void OnGenreChanged() { base.FirePropertyChanged("Genre"); } partial void OnListPriceChanged() { base.FirePropertyChanged("ListPrice"); } partial void OnListPriceCurrencyChanged() { base.FirePropertyChanged("ListPriceCurrency"); } partial void OnPlayerInfoChanged() { base.FirePropertyChanged("PlayerInfo"); } partial void OnProductDescriptionChanged() { base.FirePropertyChanged("ProductDescription"); } partial void OnProductIDChanged() { base.FirePropertyChanged("ProductID"); } partial void OnProductImageUrlChanged() { base.FirePropertyChanged("ProductImageUrl"); } partial void OnProductNameChanged() { base.FirePropertyChanged("ProductName"); } partial void OnProductTypeIDChanged() { base.FirePropertyChanged("ProductTypeID"); } partial void OnPublisherChanged() { base.FirePropertyChanged("Publisher"); } partial void OnRatingChanged() { base.FirePropertyChanged("Rating"); } partial void OnRatingUrlChanged() { base.FirePropertyChanged("RatingUrl"); } partial void OnReleaseDateChanged() { base.FirePropertyChanged("ReleaseDate"); } partial void OnSystemNameChanged() { base.FirePropertyChanged("SystemName"); } #endregion } </code></pre> <p>Of course MSDN code can seen as “toy code” for educational purposes but is anyone doing anything like this in the <em>real</em> world of Silverlight development?</p>
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    1. COPretty inflammatory title - any reason you're splashing someone's name and the word "violating" around in the same sentence?
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    2. COOtaku: My reasoning is explicitly stated in the question body text.
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    3. CONo, it's not reason for targetting a person. You're specifically calling out an individual, thus potentially smearing them because of your own misunderstanding. Secondly, Shawn would have to have an editor to approve what is published, but I don't seeing you calling out MSDN for any violation or the particular editor's name. Finally, and most importantly, if you read the the article, Shawn specifically says **This example does not necessarily represent how actual code would be used. It is simply designed to explain the pattern.**. I've flagged this post as offensive.
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