Use scrollPhysics.allowImplicitScrolling to configure scrollable semantics#20210
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jonahwilliams merged 3 commits intoflutter:masterfrom Aug 8, 2018
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How does one get to the end of a tab bar that has too many items to fit on screen? This sounds like once it gets to the last visible tab, it jumps to the tab body, but what if the tab bar has a bunch of tabs that are offscreen, but scrollable into view? How would I know that as an accessible interface user? |
gspencergoog
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Aug 7, 2018
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@gspencergoog you need to explicitly scroll with two fingers on either the tab body or the page |
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The tab bar labels also describe 3 of N, 4 of N |
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Got it. Cool. Sounds like a good change. |
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When a user navigates to the end of a visible viewport, there are two behaviors that Talkback supports: 1) it can attempt to scroll the next element from the current viewport into view, like in a List or 2) it can continue the a11y traversal as if the offscreen elements aren't there.
The latter behavior isn't exposed by us, but is necessary for a widget such as a TabBar - with implicit scrolling enabled a user would have to navigate to the end of the scrollable tabs before they can navigate into the tab body. With this change, we can configure it such that reaching the end of the visible tabs will immediately move to the tab body instead.
We already have this information on the framework side with https://master-docs-flutter-io.firebaseapp.com/flutter/widgets/ScrollPhysics/allowImplicitScrolling.html
Fixes #19917