GridView, DataPager and Virtualization issue

[Gabriel]

I'm using a GridView, DataPager and VirtualQueryableCollectionView for loading my data.  The loading part is working as expected, but I see some glitch and I'm not sure if it's a issue with your controls or a setting that I'm missing somewhere.

This is the issue:

1. I'm loading/navigating to a new page, I can see the "+" sign from the details row for 10 items.
2. The data is loaded and shown in the UI, but I still can see 10 more "+" sign below without the vertical scrollbar. This is not expexted.
3. I navigate to another page and come back to a previously loaded page, and everything look as expected.

I've attach an image that show the 3 state above.

Thanks

[Vlad]

Hi Gabriel,

 Can you post LoadSize/PageSize settings for the virtual collection?

All the best,
Vlad
the Telerik team

[Gabriel]

My LoadSize and PageSize are set to 10 when creating the virtual collection.

[Gabriel]

I've set a breakpoint in the RowLoaded event of the GridView, I can see that the e.Row.DataContext is set to an object type = object{DynamicClass1}, which I did not request. I do not think it's coming from the VirtualQueryableCollectionView that is bind to my DataPager.

[Vlad]

Hello,

 This class is from the virtual collection. The class is just a temporary dynamic copy of the original data item (with properties) since the item is not yet loaded. When the real item is loaded this temporary item will be replaced.

Best wishes,
Vlad
the Telerik team

[Gabriel]

My issue is that they are still showing in the gridview (see second gridview in the image on the original post), I have to navigate away and come back to see them disappears

[Vlad]

Hello,

 I've tried your scenario using our latest official binaries (Q2 2011 SP1) however everything worked as expected. You can check the attached project for reference. 

Regards,
Vlad
the Telerik team

[Gabriel]

Thanks Vlad,

based on your solution, I have found that the EnableRowVirtualization="False" was set to the grid and was the cause of this behavior.

[Kazimierz]

Hi Vlad,
I know this topis is quite old, yet still I found a strange behavior in your attached project which also takes place in project I am currently developing. I wanted to add filtering to your grid so in constructor of MainPage just after view initialization I added a filterDescriptor to it. It looks like this:

var view = new VirtualQueryableCollectionView<MyObject>() { LoadSize = 10, PageSize = 10, VirtualItemCount = 1000 };
            view.FilterDescriptors.Add(
                new Telerik.Windows.Data.FilterDescriptor()
                    {
                        Member = Name,
                        MemberType = typeof(string),
                        Value = "4",
                        Operator = FilterOperator.Contains
                    }
                );
            view.ItemsLoading += (s, e) =>
            {
                view.Load(e.StartIndex, from i in Enumerable.Range(e

                (....)

Unfortunatelly this little piece of code immediatly throws an "ArgumentOutOfRangeException". This exception also occurs in my current project when I clear FilterDescriptors of VirtualQueryableCollectionView and then try to add a new one (s it is not like here - in my project I can add first filter, problems start when I clear the descriptor collection). Do you know what causes those exceptions?