Parent vertical scrollbar not activating properly in hierarchy with row virtualisation turned on

[George]

 Hi,

This looks like a bug in Kendo UI Grid. Please try the following:

a) On the hierarchy example, turn off paging and turn on scrolling, but set the Employees grid to be scrollable. The scroll bar will then correctly take account of the child (orders) grid.

b) Now set .Scrollable(scrollable => scrollable.Virtual(true)) in the parent grid. The vertical scroll bar is no longer active, making scrolling in the child grid impossible.

This really needs to be fixed. It is quite common to have very large ( over 10000 row) grids, requiring row virtualisation to preserve stable behaviour. This feature effectively makes it impossible to reliably implement a deep hierarchy, as far as I can see. It looks as though, when row virtualisation is turned on on the parent, it fails to refresh the vertical scrollbar when the child grid is expanded. If there is an event trap I can put in to force the issue that would be much appreciated. Note that I am not prepared either a) to put pagination in the child grid or b) put scrolling, as it messes up the child geometry (pushing all the columns over). As I say, if you turn off virtualisation, it works ok, until the row number becomes large, at which point the whole thing starts to become unstable (load failures or very long load times).

At the very least, if you can give me a script to turn on the parent scrollbar on detail expand, that would do for now.

Thanks,
George

[Daniel]

Hello George,

This is not supported. The virtual scroller cannot know what would be the height of the detail be and so it cannot calculate the total height. There isn't a way to enable this scenario with custom code. Even if the scrollbar height is updated after the detail Grids have been bound, the Grid will still calculate the total height based on the master rows height so the pages will not be correctly shown. 

Regards,
Daniel
Telerik