Broken grouped columns in header

[youngvan]

Here a description of my problem:
I usually use virtualX mode, because tables have more then 20 columns and fast sorting is necessary.
Also tables header consist of 3-5 rows grouped by columns. When I try to scroll table to the right side it looks like grouped columns aren't placed in proper positions.

I'll try to show it on this example: http://paramquery.com/pro/demos/group_columns
If you enable virtualX mode and try to make cells in header a little bit wider you will see it -just try to scroll table horizontally .
For more proper understanding of the problem I attached a long pic(image 1) where you can see how header changes during the horizontal scrolling.

Next problem based on first one - it's wrong sorting. See second attached pic. On this pic virtualX is enabled and table width set to 720px;

This problem  doesn't exist if virtualX is disabled.
I can't disable virtualX or virtualY modes -I work with a lot of data. How I can fix that issue?
Thanks in advance!

Image 1: http://s4.postimg.org/xzd7rvg97/scroll_bug_with_header.jpg
Image 2: http://s4.postimg.org/tax7wor2l/720px_wrong_sort.jpg

[paramvir]

1) Grouped columns rely on rowspan and colspan to layout the header which doesn't work well when only the cells visible in the viewport have to be rendered in virtual mode, so it has to be non virtual mode for columns or x-axis.

If you have to display lot number of rows on a single page, you can keep virtualY as true while virtualX as false.

2) Second screenshot is too small to see the issue. Kindly post a bigger screenshot along with a small test case.

[youngvan]

On this pic I used the same data and params as in demo: http://paramquery.com/pro/demos/group_columns
Just virtualX was enabled and width of table was set to 720 px. It looks like some columns in header were placed in wrong positions so sorting was broken as well.

[youngvan]

In some reports I have too many rows and columns, so that's why I need to have both modes: virtualX and virtualY enabled. It's very critical issue for me.
Any ideas?

[paramvir]

How many columns do you have.

As discussed earlier, there is a limitation if you use {virtualX : true } then grouped cells in the header won't be laid properly.

I would check if there is something that can be done about it in next version probably 2.1.2.

[youngvan]

How many columns do you have.

It depends on data. It can be 10, 20 or even up to 50.
virtualX is enabled only if quantity of columns is more than 10.

I would check if there is something that can be done about it in next version probably 2.1.2.

It would be great! I'm looking forward to checking a new version.

[youngvan]

Here is a demo with mentioned problems: http://nashepole.com.ua/demo/

Broken header columns: As I mentioned before- during horizontal scroll you can notice how cells change positions in header and "jump" in wrong places
Sorting problem: try to scroll horizontally to the end and sort the last column for example.

[paramvir]

Yes I got it.

Both the issues are due to incompatibility of virtualX with grouped cells.

[paramvir]

Have you looked into and tried delegate scrolling?

scrollModel: { pace: 'optimum' }

It won't make scrolling any faster but it would provide a reasonable User experience.