Beta Docs ?

[Marcus Lambert]

 

Can someone point me in the right direction for the beta docs for data virtualization
Thanks

[Maya]

Hello Marcus Lambert,

We are in the process of including an article on the subject in our online documentation, under the ConsumingData section. It will be available together with our next Q3 2010 version that is to be released this November. For the time being you may take a look at our demos for Data Vizualization. 
Meanwhile, we will definitely appreciate your feedback in case you have any suggestions or requirements on the topic. 
 

Sincerely yours,
Maya
the Telerik team

[Marcus Lambert]

Would be good to take a early look at the docs, can I submit a ticket for them as I am finding the current demo not that enlightening.

[Maya]

Hello Marcus Lambert,

As the case of handling a lot of data is quite common, the requirement for fast data processing becomes more and more indispensable.  The result of this necessity is the Data Virtualization technique that ensures much better performance as well as user experience improvements.

When working with the UI components that enable UI virtualization, you may take advantage of the above mentioned technique by implementing the newly created VirtualQueryableCollectionView class. It enables you to benefit from the on-demand data loading to smooth scrolling with UI virtual components.

The VirtualQueryableCollectionView provides you with the following important members:

• LoadSize property  – defines the maximum number of items requested at once;
• VirtualItemCount property - defines the total number of items available on the server-side;
• ItemsLoading event - will be raised when the collection is requesting item at some index and this item is not already loaded. The arguments in this event are as follows: 

         -  StartIndex - requested item index;
         -   ItemCount - number of requested items (can be less than or equal to the LoadSize).
          
           In order to utilize the VirtualQueryableCollectionView class, you may take the following approach (the example below demonstrates the case when working with WCF RIA Services):

C#:

public MainPage()
        {
            InitializeComponent();

            var context = new NorthwindDomainContext();
            var query = context.GetOrder_DetailsQuery().OrderBy(o => o.OrderID);
            query.IncludeTotalCount = true;

            var view = new VirtualQueryableCollectionView() { LoadSize = 10, VirtualItemCount = 100 };
            view.ItemsLoading += (s, e) =>
            {
                context.Load<Order_Detail>(query.Skip(e.StartIndex).Take(e.ItemCount)).Completed += (sender, args) =>
               {
                   var lo = (LoadOperation)sender;
                   if (lo.TotalEntityCount != -1 && lo.TotalEntityCount != view.VirtualItemCount)
                   {
                       view.VirtualItemCount = lo.TotalEntityCount;
                   }

                   view.Load(e.StartIndex, lo.Entities);
               };
            };

            DataContext = view;
        }

XAML:

<telerik:RadGridView ItemsSource="{Binding}" />

Regards,
Maya
the Telerik team

[Marcus Lambert]

Have the documents been updated yet as I can seem to find any infomation in the current set online ?
Thanks

[Maya]

Hi Marcus Lambert,

You may follow up this link. The documentation has been added in the RadGridView section so far, but it will be included in the Consuming Data section as well.
We will appreciate your feedback on the topic.
 

Greetings,
Maya
the Telerik team

[Marcus Lambert]

Hi Maya,
Thanks for this, Its a start...  I am interested to know how to use it with the grid and doing Sorts and custom filters etc.
Marcus

[Maya]

Hi Marcus Lambert,

I believe you have got information on the topic in the other support thread you have started - VirtualQuerableCollectionView and customFilter. 

Regards,
Maya
the Telerik team