StylesPreview: Fix endless loop of ratio calculations when on the threshold of a scrollbar #57090
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
andrewserong
added
[Type] Bug
|
Size Change: +106 B (0%) Total Size: 1.71 MB
ℹ️ View Unchanged
|
|
Flaky tests detected in 3ad023e. 🔍 Workflow run URL: https://github.com/WordPress/gutenberg/actions/runs/7241395118
|
ramonjd
approved these changes
Dec 15, 2023
There was a problem hiding this comment.
Tested in Firefox, Chrome, Safari and Edge
✅ Can confirm it fixes the dancing styles preview panes. I could only reproduce on Chrome
✅ Also, the borders of the style variation previews look good on all browser in mobile view
LGTM
Thanks for going deep on this one, and removing a weird bug.
Do you think much of the workaround effort could be spared if we removed 'motion.div'? I'm not sure, but I'm assuming it's handling animations and therefore layout.
Just wondering if the old fashioned iframe.onLoad + frame.document.body.offsetHeight would be simpler 🤷🏻
|
|
|
Thanks for the review! 🙇
Good questions! It seems some of the animations are a bit dependent on I do think this component is probably doing a little too much heavy lifting when it comes to determining ratios. Like perhaps another way of doing it would be to have a couple of hard-coded ratios that the component uses depending on a threshold size, so instead of a whole bunch of multiplication, we could just swap out one or two classes (or constants) or something? Still, it's an interesting problem when trying to get a component to perform changes reactively to the container width. I suspect there's likely one or two other components that might have this problem, too. For now, I'll leave the implementation like this (and since it's the end of the week). If there's no objections, I'll merge this one in on Monday, and happy to look into follow-ups to go for a simpler / stripped down approach! |
…eshold of a scrollbar
andrewserong
force-pushed
the
fix/dancing-styles-preview-in-global-styles-sidebar
branch
from
32a33fe
to
3ad023e
Compare
andrewserong
deleted the
fix/dancing-styles-preview-in-global-styles-sidebar
branch
artemiomorales
pushed a commit
that referenced
this pull request
Jan 4, 2024
…eshold of a scrollbar (#57090) * StylesPreview: Fix endless loop of ratio calculations when on the threshold of a scrollbar * Revert stray line
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
What?
Similar issue to #55112
Fix the
StylesPreviewcomponent so that it doesn't endlessly "dance" when the viewport height means that the preview's container is right at the threshold of a scrollbar appearing.Why?
As described in #55112 (comment) the ratio calculations in the
StylesPreviewcomponent can easily wind up in an endless loop when a scrollbar is shown or hidden. It goes something like this:This issue will only be apparent at very particular viewport heights, and depending on the number of previews present. I could reproduce this issue reliably in Chrome on Mac at the following viewport heights:
568pxviewport height663pxviewport heightHow?
TL;DR — don't recalculate ratio for these previews if the change in width is only quite small (and not worth the penalty of an infinite loop)
Long story:
The fix is a little convoluted, but required a few steps to avoid an infinite loop, and keep things performant (as far as I can tell):
250ms).0.1— this is a big enough threshold to account for the show/hiding of the scrollbar, without having a negative effect (subjectively) on the appearance of the previewsWhile I was at it, I've also fixed an issue with the preview iframes not filling their containers in mobile viewports.
Testing Instructions
trunksee if you can replicate the dancing previews issue by using the viewport heights from the "Why?" section above. The key screens to look at are the root of global styles in the right hand sidebar, and the style variations screen.Testing Instructions for Keyboard
Screenshots or screencast
Global styles (before — trunk)
2023-12-15.14.27.55.mp4
Style variations (before — trunk)
2023-12-15.14.27.18.mp4
Global styles (with this PR applied)
2023-12-15.14.25.30.mp4
Style variations (with this PR applied)
2023-12-15.14.26.00.mp4