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    <p>I use lazily constructed, auto-updating collections:</p> <pre><code>public class BasketModelView { private readonly Lazy&lt;ObservableCollection&lt;AppleModelView&gt;&gt; _appleViews; public BasketModelView(BasketModel basket) { Func&lt;AppleModel, AppleModelView&gt; viewModelCreator = model =&gt; new AppleModelView(model); Func&lt;ObservableCollection&lt;AppleModelView&gt;&gt; collectionCreator = () =&gt; new ObservableViewModelCollection&lt;AppleModelView, AppleModel&gt;(basket.Apples, viewModelCreator); _appleViews = new Lazy&lt;ObservableCollection&lt;AppleModelView&gt;&gt;(collectionCreator); } public ObservableCollection&lt;AppleModelView&gt; Apples { get { return _appleViews.Value; } } } </code></pre> <p>Using the following <code>ObservableViewModelCollection&lt;TViewModel, TModel&gt;</code>:</p> <pre><code>namespace Client.UI { using System; using System.Collections.Generic; using System.Collections.ObjectModel; using System.Collections.Specialized; using System.Diagnostics.Contracts; using System.Linq; public class ObservableViewModelCollection&lt;TViewModel, TModel&gt; : ObservableCollection&lt;TViewModel&gt; { private readonly ObservableCollection&lt;TModel&gt; _source; private readonly Func&lt;TModel, TViewModel&gt; _viewModelFactory; public ObservableViewModelCollection(ObservableCollection&lt;TModel&gt; source, Func&lt;TModel, TViewModel&gt; viewModelFactory) : base(source.Select(model =&gt; viewModelFactory(model))) { Contract.Requires(source != null); Contract.Requires(viewModelFactory != null); this._source = source; this._viewModelFactory = viewModelFactory; this._source.CollectionChanged += OnSourceCollectionChanged; } protected virtual TViewModel CreateViewModel(TModel model) { return _viewModelFactory(model); } private void OnSourceCollectionChanged(object sender, NotifyCollectionChangedEventArgs e) { switch (e.Action) { case NotifyCollectionChangedAction.Add: for (int i = 0; i &lt; e.NewItems.Count; i++) { this.Insert(e.NewStartingIndex + i, CreateViewModel((TModel)e.NewItems[i])); } break; case NotifyCollectionChangedAction.Move: if (e.OldItems.Count == 1) { this.Move(e.OldStartingIndex, e.NewStartingIndex); } else { List&lt;TViewModel&gt; items = this.Skip(e.OldStartingIndex).Take(e.OldItems.Count).ToList(); for (int i = 0; i &lt; e.OldItems.Count; i++) this.RemoveAt(e.OldStartingIndex); for (int i = 0; i &lt; items.Count; i++) this.Insert(e.NewStartingIndex + i, items[i]); } break; case NotifyCollectionChangedAction.Remove: for (int i = 0; i &lt; e.OldItems.Count; i++) this.RemoveAt(e.OldStartingIndex); break; case NotifyCollectionChangedAction.Replace: // remove for (int i = 0; i &lt; e.OldItems.Count; i++) this.RemoveAt(e.OldStartingIndex); // add goto case NotifyCollectionChangedAction.Add; case NotifyCollectionChangedAction.Reset: Clear(); for (int i = 0; i &lt; e.NewItems.Count; i++) this.Add(CreateViewModel((TModel)e.NewItems[i])); break; default: break; } } } } </code></pre>
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    1. USSam Harwell
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    1. COFor anyone using Silverlight you will need to comment out the NotifyCollectionChangedAction.Move case with something like #if !SILVERLIGHT
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      1. USdFlat
    2. COin your `NotifyCollectionChangedAction.Move` case in the `else` case there can be a bug if the NewStartingIndex is > OldStartingIndex, you can fix it by adding this code: `if(newIndex > e.OldStartingIndex) newIndex-=e.OldItems.Count;` between the remove and the insert.
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      1. USJoão Portela
    3. CO@JoãoPortela - Can you post the more of your actual change? There is no newIndex variable in the original code.
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      1. USgrantnz
 

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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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