[css-scroll-snap-2] Add snapChanged and snapChanging details #9056

DavMila · 2023-07-11T16:59:34Z

snapChanged and snapChanging details are JavaScript events which are fired when a scroller's snap target changes.

This adds some interfaces to support the definition of these events:

SnapEvent interface defines a shared event type for snapChanged and snapChanging.
SnapTargetList interface defines an object that stores one array of snap targets per x/y axis.
SnapTargetArray interface defines an object that stores a single array of snap targets.

snapChanged and snapChanging details are JavaScript events which are fired when a scroller's snap target changes.

argyleink

nice! a refined version of the previous work lookin good 👍🏻

snapChanged and snapChanging are new JavaScript events defined by the css-scroll-snap-2 spec[1]. These events are explained here[2] and will be have more details in the spec[1] when this change[3] is merged into the working group's repo. SnapEvent, added by this patch, defines the interface for these new events. Bug:1456339 [1]https://drafts.csswg.org/css-scroll-snap-2/#snapchanged-and-snapchanging [2]https://github.com/argyleink/ScrollSnapExplainers/tree/main/ [3]w3c/csswg-drafts#9056 Change-Id: Ic009ca9706de46128c7b0d68528c60a980067b2a Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4599639 Commit-Queue: David Awogbemila <awogbemila@chromium.org> Reviewed-by: Robert Flack <flackr@chromium.org> Cr-Commit-Position: refs/heads/main@{#1193240}

snapChanged is a new JavaScript event defined by the css-scroll-snap-2 spec[1]. This event is explained here[2] and will be more fleshed out in the spec[1] when this PR[3] is merged. Bug:1456339 [1]https://drafts.csswg.org/css-scroll-snap-2/#snapchanged-and-snapchanging [2]https://github.com/argyleink/ScrollSnapExplainers/tree/main/ [3]w3c/csswg-drafts#9056 Change-Id: I68015f6a96f5f0a835d5731fcc85441bfbf84368 Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4599849 Commit-Queue: David Awogbemila <awogbemila@chromium.org> Reviewed-by: Steve Kobes <skobes@chromium.org> Cr-Commit-Position: refs/heads/main@{#1194164}

snapchanged[1] (explainer[2]) should fire when a scroller snaps to a different element than it was previously snapped to. This pull request[3] will copy the details from the explainer to the spec. Bug:1456339 [1]https://drafts.csswg.org/css-scroll-snap-2/#snapchanged-and-snapchanging [2]https://github.com/argyleink/ScrollSnapExplainers/tree/main/ [3]w3c/csswg-drafts#9056 Change-Id: I8e798920a2a1ffc19af9ea3f274a94db976cc87d

snapchanged[1] (explainer[2]) should fire when a scroller snaps to a different element than it was previously snapped to. This pull request[3] will copy the details from the explainer to the spec. Bug:1439807 [1]https://drafts.csswg.org/css-scroll-snap-2/#snapchanged-and-snapchanging [2]https://github.com/argyleink/ScrollSnapExplainers/tree/main/ [3]w3c/csswg-drafts#9056 Change-Id: I8e798920a2a1ffc19af9ea3f274a94db976cc87d

snapchanged[1] (explainer[2]) should fire when a scroller snaps to a different element than it was previously snapped to. This pull request[3] will copy the details from the explainer to the spec. Bug:1456339 [1]https://drafts.csswg.org/css-scroll-snap-2/#snapchanged-and-snapchanging [2]https://github.com/argyleink/ScrollSnapExplainers/tree/main/ [3]w3c/csswg-drafts#9056 Change-Id: I8e798920a2a1ffc19af9ea3f274a94db976cc87d

…d for programmatic scrolls, a=testonly Automatic update from web-platform-tests [css-scroll-snap-2] Implement snapchanged for programmatic scrolls snapchanged[1] (explainer[2]) should fire when a scroller snaps to a different element than it was previously snapped to. This pull request[3] will copy the details from the explainer to the spec. Bug:1456339 [1]https://drafts.csswg.org/css-scroll-snap-2/#snapchanged-and-snapchanging [2]https://github.com/argyleink/ScrollSnapExplainers/tree/main/ [3]w3c/csswg-drafts#9056 Change-Id: I8e798920a2a1ffc19af9ea3f274a94db976cc87d Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4621862 Reviewed-by: Weizhong Xia <weizhonggoogle.com> Reviewed-by: Robert Flack <flackrchromium.org> Commit-Queue: David Awogbemila <awogbemilachromium.org> Cr-Commit-Position: refs/heads/main{#1219164} -- wpt-commits: fe6c0e79ae54795068e316a3ca4aea9359baf17d wpt-pr: 41959 UltraBlame original commit: 147d1bfc2e3c593d14ad50aa837b91c95341b740

…d for programmatic scrolls, a=testonly Automatic update from web-platform-tests [css-scroll-snap-2] Implement snapchanged for programmatic scrolls snapchanged[1] (explainer[2]) should fire when a scroller snaps to a different element than it was previously snapped to. This pull request[3] will copy the details from the explainer to the spec. Bug:1456339 [1]https://drafts.csswg.org/css-scroll-snap-2/#snapchanged-and-snapchanging [2]https://github.com/argyleink/ScrollSnapExplainers/tree/main/ [3]w3c/csswg-drafts#9056 Change-Id: I8e798920a2a1ffc19af9ea3f274a94db976cc87d Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4621862 Reviewed-by: Weizhong Xia <weizhong@google.com> Reviewed-by: Robert Flack <flackr@chromium.org> Commit-Queue: David Awogbemila <awogbemila@chromium.org> Cr-Commit-Position: refs/heads/main@{#1219164} -- wpt-commits: fe6c0e79ae54795068e316a3ca4aea9359baf17d wpt-pr: 41959

fantasai · 2023-11-20T22:07:03Z

Not seeing "SnapChanged" in the CSSWG's ML archive... was there a CSSWG resolution for it somewhere? https://www.w3.org/Search/Mail/Public/search?type-index=www-style&index-type=t&keywords=SnapChanged&search=Search

argyleink · 2023-11-20T22:47:10Z

Not seeing "SnapChanged" in the CSSWG's ML archive... was there a CSSWG resolution for it somewhere? https://www.w3.org/Search/Mail/Public/search?type-index=www-style&index-type=t&keywords=SnapChanged&search=Search

here!

…d for programmatic scrolls, a=testonly Automatic update from web-platform-tests [css-scroll-snap-2] Implement snapchanged for programmatic scrolls snapchanged[1] (explainer[2]) should fire when a scroller snaps to a different element than it was previously snapped to. This pull request[3] will copy the details from the explainer to the spec. Bug:1456339 [1]https://drafts.csswg.org/css-scroll-snap-2/#snapchanged-and-snapchanging [2]https://github.com/argyleink/ScrollSnapExplainers/tree/main/ [3]w3c/csswg-drafts#9056 Change-Id: I8e798920a2a1ffc19af9ea3f274a94db976cc87d Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4621862 Reviewed-by: Weizhong Xia <weizhonggoogle.com> Reviewed-by: Robert Flack <flackrchromium.org> Commit-Queue: David Awogbemila <awogbemilachromium.org> Cr-Commit-Position: refs/heads/main{#1219164} -- wpt-commits: fe6c0e79ae54795068e316a3ca4aea9359baf17d wpt-pr: 41959 UltraBlame original commit: 19a2a65c56c4a7e663a91296ed8b3bd78a29b440

…d for user scrolls, a=testonly Automatic update from web-platform-tests [css-scroll-snap-2] Implement snapchanged for user scrolls snapchanged[1] (explainer[2]) should fire when a scroller snaps to a different set of elements than it was previously snapped to. This pull request[3] will copy the details from the explainer to the spec. This patch implements snapchanged for user scrolls. kSnappedToTolerance is increased to 1.0 because there appear to be some differences between the way that fractional snap offsets are handled in cc versus in blink. E.g. when snapping to a target, blink may round a fractional offset down to the nearest integer while cc may round it up as in this codepen[4] where a keyboard scroll snap ends at 134px while a wheel scroll ends at 135px when snapping to the lower box. Bug:1439807 [1]https://drafts.csswg.org/css-scroll-snap-2/#snapchanged-and-snapchanging [2]https://github.com/argyleink/ScrollSnapExplainers/tree/main/ [3]w3c/csswg-drafts#9056 [4]https://codepen.io/awogbemila/pen/JjxEzNm Change-Id: Id9fd24df3df27d3cea202f2efb2ad09b6e6a0fec Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4994876 Reviewed-by: Steve Kobes <skobes@chromium.org> Commit-Queue: David Awogbemila <awogbemila@chromium.org> Cr-Commit-Position: refs/heads/main@{#1222911} -- wpt-commits: 6287285e2da1af4fa45c66a4d7f510bff60acc6c wpt-pr: 42891

…apchanged for user scrolls", a=testonly Automatic update from web-platform-tests Revert "[css-scroll-snap-2] Implement snapchanged for user scrolls" This reverts commit 5fe9b8c1093df2e89604d785b5acfc8f7323c6c8. Reason for revert: Causing breakage in Webkit leak builder https://ci.chromium.org/ui/p/chromium/builders/ci/WebKit%20Linux%20Leak Original change's description: > [css-scroll-snap-2] Implement snapchanged for user scrolls > > snapchanged[1] (explainer[2]) should fire when a scroller snaps to a > different set of elements than it was previously snapped to. > This pull request[3] will copy the details from the explainer to the > spec. > > This patch implements snapchanged for user scrolls. > > kSnappedToTolerance is increased to 1.0 because there appear to be > some differences between the way that fractional snap offsets are > handled in cc versus in blink. E.g. when snapping to a target, > blink may round a fractional offset down to the nearest integer > while cc may round it up as in this codepen[4] where a keyboard > scroll snap ends at 134px while a wheel scroll ends at > 135px when snapping to the lower box. > > Bug:1439807 > > [1]https://drafts.csswg.org/css-scroll-snap-2/#snapchanged-and-snapchanging > [2]https://github.com/argyleink/ScrollSnapExplainers/tree/main/ > [3]w3c/csswg-drafts#9056 > [4]https://codepen.io/awogbemila/pen/JjxEzNm > > Change-Id: Id9fd24df3df27d3cea202f2efb2ad09b6e6a0fec > Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4994876 > Reviewed-by: Steve Kobes <skobes@chromium.org> > Commit-Queue: David Awogbemila <awogbemila@chromium.org> > Cr-Commit-Position: refs/heads/main@{#1222911} Bug: 1439807 Change-Id: I0c0c3dcb5aa18790d8dce2c3965696ae2d305361 No-Presubmit: true No-Tree-Checks: true No-Try: true Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5021928 Owners-Override: Fred Shih <ffred@chromium.org> Auto-Submit: Fred Shih <ffred@chromium.org> Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com> Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com> Cr-Commit-Position: refs/heads/main@{#1223240} -- wpt-commits: 101005c254f529ba5b1b20bbd849d40dc5cafe5d wpt-pr: 43092

…apchanged for user scrolls", a=testonly Automatic update from web-platform-tests Reland "[css-scroll-snap-2] Implement snapchanged for user scrolls" This is a reland of commit 5fe9b8c1093df2e89604d785b5acfc8f7323c6c8 A leak detection builder[1] was failing, seemingly because the test finished without waiting for a promise. The "Bug:" association in the commit description is also corrected. Original change's description: > [css-scroll-snap-2] Implement snapchanged for user scrolls > > snapchanged[1] (explainer[2]) should fire when a scroller snaps to a > different set of elements than it was previously snapped to. > This pull request[3] will copy the details from the explainer to the > spec. > > This patch implements snapchanged for user scrolls. > > kSnappedToTolerance is increased to 1.0 because there appear to be > some differences between the way that fractional snap offsets are > handled in cc versus in blink. E.g. when snapping to a target, > blink may round a fractional offset down to the nearest integer > while cc may round it up as in this codepen[4] where a keyboard > scroll snap ends at 134px while a wheel scroll ends at > 135px when snapping to the lower box. > > Bug:1439807 > > [1]https://drafts.csswg.org/css-scroll-snap-2/#snapchanged-and-snapchanging > [2]https://github.com/argyleink/ScrollSnapExplainers/tree/main/ > [3]w3c/csswg-drafts#9056 > [4]https://codepen.io/awogbemila/pen/JjxEzNm > > Change-Id: Id9fd24df3df27d3cea202f2efb2ad09b6e6a0fec > Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4994876 > Reviewed-by: Steve Kobes <skobes@chromium.org> > Commit-Queue: David Awogbemila <awogbemila@chromium.org> > Cr-Commit-Position: refs/heads/main@{#1222911} [1]https://ci.chromium.org/ui/p/chromium/builders/ci/WebKit%20Linux%20Leak Bug: 1500972,1456339 Change-Id: I8c1dd52d5ae55a1eb756d95faf9990bd2de6e5e4 Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5022556 Reviewed-by: Steve Kobes <skobes@chromium.org> Commit-Queue: David Awogbemila <awogbemila@chromium.org> Cr-Commit-Position: refs/heads/main@{#1223681} -- wpt-commits: 1c79efa4efe301b0ec15bf95dc4d3654b5cd7494 wpt-pr: 43105