asynchronous balance and bring into view

[Tomasz]

Hi Telerik Team.

In my project I’m using Pivot (collection of tabs) and RadDataBoundListBox as template for PivotItem (single tab that is collection of fields). Collections of data which I’m using can be big, so I use "asynchronous balance". In some cases I want to give user ability to scroll one of fields into view (in example: When initially most fields are filled and I want to show him quickly first field that isn’t). To achieve this I change pivot SelectedIndex and use BringIntoView method on list. In most cases it works well, but when list is short (all items will fit into ViewPort) and list didn’t loaded yet field that I want to scroll into view (because of "asynchronous balance"), using BringIntoView will make list dissapear. Disabling "asynchronous balance" fix problem but I would like to use it since it boost performance. I managed to reproduce issue in separate project, but unfortunatly I don't know how to send it to you (allowed extensions are only .jpg, .jpeg, .gif, .png)

 

Best regards

Tomasz

 

[Deyan]

Hi Tomasz,

We are willing to investigate the issue. Can you please open a new support ticket and attach your project in a ZIP archive? Attaching ZIP archives in public forums is not allowed.

Regards,
Deyan
Telerik

[Tomasz]

Hello Deyan 

Unfortunately I don’t have any tickets. My company too - because of license expiration. I’ve uploaded zip on DropBox. Please let me know when you download it so I could remove it from there. 

Here is a link:
https://dl.dropboxusercontent.com/u/13714850/PivotApp4.zip

Best regards
Tomasz

[Deyan]

Hi Tomasz,

Thanks for writing and for the project.

When clicking on the Button which changes the pivot index I can see a correctly loaded listbox, i.e. items are there and no obvious visual glitches are present. Are you sure the project you've prepared reproduces the scenario?

As for your license, we normally support customers who have a valid license. Even if we identify an issue right now which we eventually fix in an upcoming build, you will not be able to download it as your license has expired.

Please consider renewing it to be able to have access to latest internal builds and all future releases.

Regards,
Deyan
Telerik

[Tomasz]

Hi Deyan 

Please forgive me. I didn't notice that this error does not occur every time. Please try to run application with debugger. I’ve also noticed that on lumia 520 it happens more often.

As for license I’m also aware that my company needs to renew subscription to obtain any update. As far as I know we are going to do this shortly

Best regards

Tomasz

[Deyan]

Hi Tomasz,

Thanks for writing back.

We will continue investigating and will address any issues we encounter. For the time being we will consider this thread closed. As a workaround for any issues of this kind, try setting the IsAsyncBalanceEnabled = false. If you use not so complex templates for the listbox, you will not experience any performance issues anyway.

If you think there is an easier way of reproducing the issue, let us know by reopnening this thread.

Regards,
Deyan
Telerik

[Bikramjit]

I also faced the same issue while working with jumplist in my project and independently reached the same conclusion that setting IsAsyncBalanceEnabled to false fixes the anomaly. Otherwise I face blank screen or upper portion of the screen remaining blank and items showing up only in the bottom half of the page. Slight scrolling action on the phone screen brings the jumplist items back in correct form. In my case I am calling BringIntoView() after changing value of sorting criteria defined earlier via GenericSortDescriptor.KeySelector.

As mentioned by the previous user, it only happens when there are a few items in the viewport. Try with only 2-3 items to the list and call bringIntoView on the last item. I suggest that the item should be an object that has an id property on which GenericSortDescriptor.KeySelector is set. Try changing that value and then call bringIntoView on that item object. The intention in the production application is to bring that item into the view that has just been modified.

As a side note, there is another issue that I observed. If the sticky headers are enabled, they hide the item that has been brought into view port at the top. I feel this should also be fixed as it is quite important for user experience.

Just wanted to add my comments so that Telerik team can get a feedback that more than one developer faced this issue. Telerik team: Please fix this behavior or provide a remedial advice if something else must be configured to use IsAsyncBalance in enabled form.

[Deyan]

Hello Bikramjit,

Thanks for writing.

We are currently working on resolving the BringIntoView+AsyncBalance issue. It seems to not be easily reproducible. We want to see what exactly causes it so that we provide an adequate fix.

As for the BringIntoView+StickyHeader issue: we have resolved this issue and the fix is available in our Q3 2013 Beta release. It will also be included in the official release. If after updating to the Beta assemblies the StickyHeader issue persists, please let us know so that we can quickly address any other possible issues for our official release.

Regards,
Deyan
Telerik