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    <p>First of all, your record count is really nothing in front of wpf's ListView as it makes use of the VirtualizingStackPanel.</p> <p>Apart from the exact solution of PropertyChange Notification, you should also consider having a look at the concept of <a href="http://blogs.msdn.com/b/charlie/archive/2007/12/09/deferred-execution.aspx" rel="nofollow noreferrer">deferred execution</a>. You seem to convert everything into a list which would lead to force enumeration of the result set at once. </p> <p>Let us consider your code:</p> <pre><code>_people= GetAll().ToList(); //The result of GetAll is enumerated and a solid list is created List&lt;Person&gt; allPeople = (from person in _people select new PersonViewModel(person)).ToList(); // another list created AllPeople = new ObservableCollection&lt;PersonViewModel&gt;(allPeople); // ObservableCollection created out of list </code></pre> <p>Let us tweak it a bit:</p> <pre><code>_people= GetAll(); // The result is just referred by _people IEnumerable&lt;Person&gt; allPeople = (from person in _people select new PersonViewModel(person)); // IEnumerable is just provided with a query. No other operation is done AllPeople = new ObservableCollection&lt;PersonViewModel&gt;(allPeople); // The ObservableCollection requests element from allPeople // which in turn requests from the query // which in turn requests from _people // which enumerates the result of GetAll() and yields the result. </code></pre> <p>Hence you can avoid the creation of temporary lists.</p> <p>Further, even the <code>GetAll()</code> method could be made to return an IEnumerable if it doesn't.</p> <p>You could take a look at <br> <a href="http://msdn.microsoft.com/en-us/library/system.collections.ienumerable.aspx" rel="nofollow noreferrer">IEnumerable</a> <br> <a href="http://msdn.microsoft.com/en-us/library/system.linq.iqueryable.aspx" rel="nofollow noreferrer">IQueryable</a> <br> <a href="http://msdn.microsoft.com/en-us/library/9k7k7cf0(VS.80).aspx" rel="nofollow noreferrer">yield</a></p>
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    1. POHow to Refresh a ListItem in WPF ListView ,CollectionViewSource in MVVM
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    1. COThanks for the suggestion to make the List into IEnumerable Collection. My Main concern comes Here IEnumerable<Person> allPeople = (from person in _people select new PersonViewModel(person)); as I have lot of methods calling to set Properties on the PersonViewModel.It use to take a lot of time for each record to go through all methods. But now after Putting it to IEnumerable it doesnt take much time but when the debug point goes to AllPeople = new ObservableCollection<PersonViewModel>(allPeople); line it takes some noticible time to load
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    2. CO@user311945: At one point anyways the solid list has to be created and hence the time. But it should not take much time as you specify. Should be less than a second for thousands of items. Can you post the code for PersonViewModel constructor and other things that you feel consume time. Use the Stopwatch class.
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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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