ParamQuery grid support forum

General Category => Bug Report => Topic started by: paulguz on February 06, 2018, 05:55:42 pm

Title: Flickery scrolling on iPad
Post by: paulguz on February 06, 2018, 05:55:42 pm

Hi,

I'm evaluating ParamQueryPro 5.1 on an iPad Air running iOS 11.2.5.

When scrolling a grid with grouped columns, the scrolling can be very flickery indeed.  Sometimes cells are not rendered (are blank).

You can witness this yourself by viewing your own Export Grouped Columns demo at paramquery.com/pro/demos

Regards,

Paul

Title: Re: Flickery scrolling on iPad
Post by: paulguz on February 08, 2018, 06:50:09 pm

Any thoughts?  Our purchase of a Pro licence is contingent on this being fixed.

Title: Re: Flickery scrolling on iPad
Post by: paramvir on February 09, 2018, 05:12:10 pm

For performance reasons and to support unlimited number of rows and columns, in pqgrid, cells are rendered only in the viewport, which means cells are created and destroyed continuously as the view is scrolled.

In touch devices, scroll event is fired at a longer interval, resulting in skipping of rendering and painting of some of the new cells.

This skipping happens only when the view is scrolled.

When scrolling is stopped, all the cells are rendered in viewport, thus from our viewpoint this is not an issue and there is no plan to change it.

Title: Re: Flickery scrolling on iPad
Post by: paulguz on February 09, 2018, 05:41:20 pm

I'm afraid that doesn't match our experience.  Cells are left blank even after scrolling.

The flickering whilst scrolling isn't a good experience, either.

Please see the below video.

https://datapa-my.sharepoint.com/:v:/p/pguz/EXXhIPTprBZIsHyuGiX-3PcBY2IvhVoKvzf_Wnldo_yYhA?e=AYc2iQ

Title: Re: Flickery scrolling on iPad
Post by: paramvir on February 09, 2018, 06:07:41 pm

Do you face this issue with grouped columns only or with all examples.

Title: Re: Flickery scrolling on iPad
Post by: paulguz on February 09, 2018, 06:14:38 pm

It seems to be only with grouped columns.

Title: Re: Flickery scrolling on iPad
Post by: paramvir on February 09, 2018, 06:18:49 pm

That's strange.

Is it the same issue in Chrome browser and/ or opening example in a new tab / window.

Title: Re: Flickery scrolling on iPad
Post by: paulguz on February 09, 2018, 06:26:26 pm

Yes and yes

It has to work in Safari, supporting the stock browser is of the utmost importance.

Title: Re: Flickery scrolling on iPad
Post by: paramvir on February 09, 2018, 06:28:32 pm

Ok, there is another example on grouped columns: https://paramquery.com/pro/demos/infinite

Is it the same issue with this one too?

Title: Re: Flickery scrolling on iPad
Post by: paulguz on February 09, 2018, 06:32:23 pm

No, it seems OK on that one.

Title: Re: Flickery scrolling on iPad
Post by: paulguz on March 01, 2018, 06:14:51 pm

Any more thoughts?  As previously stated, we can't purchase a Pro licence unless this is fixed.

Title: Re: Flickery scrolling on iPad
Post by: paramvir on June 06, 2018, 06:50:09 pm

Thanks for reporting issue.

The issue of cells left blank while scrolling has been identified and fix would be available in upcoming version.

Title: Re: Flickery scrolling on iPad
Post by: paulguz on June 07, 2018, 02:13:10 pm

Thanks very much.  Looking forward to trying out the new version when it comes.

Title: Re: Flickery scrolling on iPad
Post by: paramvir on July 24, 2018, 11:06:00 am

This is fixed in v5.2.0