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    <p>You're really going to create the inheritance in your view models, not your views. I'd define an <code>ItemViewModelBase</code> class that exposes <code>ItemName</code>, <code>Items</code>, and <code>SelectedItemName</code> properties and derive my view models from it. </p> <p>The views themselves don't really "inherit" per se. In fact, unless you need customization in the view, you don't need multiple views: you only need one view that presents <code>ItemViewModelBase</code> objects. </p> <p>Of course, if you do need the views to be different, you can do a certain amount of customization, e.g.:</p> <pre><code>&lt;DataTemplate DataType="{x:Type CarsViewModel}"&gt; &lt;DockPanel&gt; &lt;Label DockPanel.Dock="Top"&gt;Cars&lt;/Label&gt; &lt;local:ItemView/&gt; &lt;/DockPanel&gt; &lt;/DataTemplate&gt; </code></pre> <p>This is a cool idea for another reason. Right now, if you don't provide a data template, whenever WPF presents an object it creates a <code>TextBlock</code> containing <code>object.ToString()</code>. Implementing a generic base class gives you a way to globally override this behavior just by creating one data template, e.g.:</p> <pre><code>&lt;DataTemplate DataType="{x:Type ItemViewModelBase}"&gt; &lt;TextBlock Text="{Binding ItemName}"/&gt; &lt;/DataTemplate&gt; </code></pre> <p>That's not easier than just overriding <code>ToString()</code> to return <code>ItemName</code> (which is where I'd start), but if (for instance) you want a <code>ToolTip</code> that displays detailed information when the user mouses over it, you just add it to this one template and it works everywhere in your UI.</p>
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    1. USRobert Rossney
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    1. COThanks Robert. I am working on creating an ItemViewModelBase class right now and have a question. ItemViewModelBase is an abstract class and I want to define the appropriate properties (ItemName, Items, etc.). My Items property is an ObservableCollection: public virtual ObservableCollection<???> Items { get; set; }. What would I put as the collection type? The classes that derive form this base class will have different lists (<Person>, <Car>). Is the base view model the right place to put the property? I do want all of the derived classes to implement it so it seems so.
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    2. COOne other question. Let's say I do not need any customization of my views. I would only need one View in that case. It is not clear how I would set this up. Are suggesting is that I create a DataTemplate for ItemViewModelBase and a single view (user control) to represent it? I have not used DataTemplates with mvvm before so I'm trying to figure it out. Right now I use Unity to register my viewModels and when the veiw is created, the viewModel gets injected in the view. How would I differentiate between the drived view models when I try to create the view?
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    3. COAs far as your first question goes, I'd start out making it an `ObservableCollection<object>` and seeing if that turns out to cause any trouble. For your second question, if you create a `DataTemplate` whose `DataType` is `ItemViewModelBase`, it will be used to present all of your `ItemViewModelBase` objects unless you create a specific template for one of the subclasses. Look up data template selection on MSDN for information about how template selection works in the absence of Unity; it's pretty robust.
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