Last Updated: 22 Mar 2021 11:33 by ADMIN
Created on: 17 Dec 2020 16:43
Category: Grid
Type: Bug Report
Rows are displaced when performing browser zoom

When using row virtualization, the visible rows are miscalculated when the browser zoom is used (hold control with mouse scroll). 

The result of the miscalculation is that the first row at some point is not visible.

To reproduce the problem you should scroll to the top of the grid and see the first row.

Then start to zoom down and see how the first row is displaced.

Seems like only 50%, 100%, 150%, 200% (multiply of 50%) are calculated correctly in row virtualization



You can reproduce the bug with the attached code.

It's browser-specific and is appearing only in chromium browsers.

It could be related to the way browsers calculate the size of the elements when zooming.

Currently, there is an open bug in the chromium: https://bugs.chromium.org/p/chromium/issues/detail?id=1048147&q=component%3AUI%3EBrowser%3EZoom%20height&can=2 



Marin Bratanov
Posted on: 02 Mar 2021 12:43

Hello Wei,

I have responded in your private ticket.

Marin Bratanov
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Posted on: 01 Mar 2021 18:43
row virtualization is VERY important to our application (Rendering 10K rows is a performance requirement), with row virtualization on, it renders in 5-6 seconds. with it off, it takes up 4GB memory in blazor server and browser is hanging forever. 
but this issue reported above will mis-calculate rows in the scrolling pane, sometimes even miss a whole row. 
according to initial investigation, it is a bug from chromium - but the issue raised there says it only affect chrome not edge, but we observe the same wrong behavior in both chrome and edge
can we get some clarify on this issue, and maybe push some pressure to chromium team from telerik as telerik being a big player in web UI world might have bigger impact to the priority of this issue.