Bug 223744 - [iOS] Non-native scrolling animations are disabled
Summary: [iOS] Non-native scrolling animations are disabled
Status: NEW
Alias: None
Product: WebKit
Classification: Unclassified
Component: Scrolling (show other bugs)
Version: WebKit Nightly Build
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Nobody
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2021-03-25 05:21 PDT by Martin Robinson
Modified: 2021-04-01 05:22 PDT (History)
2 users (show)

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Description Martin Robinson 2021-03-25 05:21:52 PDT 
"Non-native" scrolling animations are disabled for iOS even when the RenderLayer specifies that the ScrollAnimator should be used. This is currently implemented via an #ifdef [1]

#if ENABLE(SMOOTH_SCROLLING) && !PLATFORM(IOS_FAMILY)
    if (m_scrollableArea.scrollAnimatorEnabled() && !behavior.contains(ScrollBehavior::NeverAnimate)) {
        m_scrollAnimation->setCurrentPosition(m_currentPosition);
        return m_scrollAnimation->scroll(orientation, granularity, step, multiplier);
    }
#endif


This bug tracks deciding whether or not it makes sense to remove this exception. An example of when this would come into play would be when a keyboard is plugged into an iOS device and the user scrolls via pageup / pagedown or the arrow keys.

1. https://github.com/WebKit/WebKit/blob/3148d6dc25355456915544ce7e6e070c7ebf213a/Source/WebCore/platform/ScrollAnimator.cpp#L103
Comment 1 Radar WebKit Bug Importer 2021-04-01 05:22:14 PDT 
<rdar://problem/76099562>