Fix: Fixed issue where changing a folder's grouping preference wouldn't update other open tabs

[ferrariofilippo]

Resolved / Related Issues

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• Closes Bug: Grouping and sorting options are not consistent between tabs/panes #16570

Notes
I'm not sure how to handle multiple panes: currently the layout is updated only when the pane is focused, to avoid wasting resources (see video below). Is this fine? Would it be better to update the layout istantly?

Steps used to test these changes

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1. Open two tabs with the same folder
2. Change sort/group option/order in a tab
3. Switch to the second tab
4. Repeat using the Sync preferences between folders setting

Panes_behaviour.mp4

[yaira2]

Would it be better to update the layout istantly?

How much of a performance difference is there?

[ferrariofilippo]

How much of a performance difference is there?

As you may think, the issue involves mainly big folders: with small ones (~ 50 items) I saw no difference.
I tested a folder with ~550 items on my laptop (i7-13650HX, 16GB): sometimes it got slightly laggy when updating both panes.
I'll leave two recordings below (sped-up 2x).

The real issue is with RAM usage: updating two panes uses twice the RAM.
In my case, updating the 550 items folder I reached a difference of ~350 MB after 7 updates (I guess we have a memory leak).
Each update required more or less 50MB per pane.
I imagine this would get worse using some layouts such as Grid

Partial_update.mp4

Complete_update.mp4

Should I push the code to update both the panes so that you can test by yourself?

[yaira2]

I think it's important to update both panes, but we should make sure that the focus remains on the active pane. While memory usage is a valid concern, I don't think it's common for users to have the same folder open in both panes and then decide to change the grouping.

[ferrariofilippo]

I think it's important to update both panes, but we should make sure that the focus remains on the active pane. While memory usage is a valid concern, I don't think it's common for users to have the same folder open in both panes and then decide to change the grouping.

Focus is fine, it was me changing it

[0x5bfa]

Code wise, looks great otherwise.

[ferrariofilippo]

As a side note, I found out there's a similar issue with layouts not being updated between panes... I remember it used to work, didn't it?

[yaira2]

I'm not certain this is doable, but it might be worth seeing if this code could be put in the layout helper as well.

[ferrariofilippo]

I'll see what I can do

[ferrariofilippo]

At the moment GetPanes() and equivalents are marked as private. If we want to allow access from other classes, I can change it to public and move the code in the helper

[yaira2]

What do you suggest?

[ferrariofilippo]

I just had a look at ModernShellPage implementation and it seems there are no "dangerous" public things, so I guess we can make it public