Files
react-native/Libraries/Components/View/ViewAccessibility.js
T
fabriziobertoglio1987 dd6325bafe TalkBack support for ScrollView accessibility announcements (list and grid) (#33180)
Summary:
This issue fixes [30977][17] . The Pull Request was previously published by [intergalacticspacehighway][13] with [31666][19].
The solution consists of:
1. Adding Javascript logic in the [FlatList][14], SectionList, VirtualizedList components to provide accessibility information (row and column position) for each cell in the method [renderItem][20] as a fourth parameter [accessibilityCollectionItem][21]. The information is saved on the native side in the AccessibilityNodeInfo and announced by TalkBack when changing row, column, or page ([video example][12]). The prop accessibilityCollectionItem is available in the View component which wraps each FlatList cell.
2. Adding Java logic in [ReactScrollView.java][16] and HorizontalScrollView to announce pages with TalkBack when scrolling up/down. The missing AOSP logic in [ScrollView.java][10] (see also the [GridView][11] example) is responsible for announcing Page Scrolling with TalkBack.

Relevant Links:
x [Additional notes on this PR][18]
x [discussion on the additional container View around each FlatList cell][22]
x [commit adding prop getCellsInItemCount to VirtualizedList][23]

## Changelog

[Android] [Added] - Accessibility announcement for list and grid in FlatList

Pull Request resolved: https://github.com/facebook/react-native/pull/33180

Test Plan:
[1]. TalkBack announces pages and cells with Horizontal Flatlist in the Paper Renderer ([link][1])
[2]. TalkBack announces pages and cells with Vertical Flatlist in the Paper Renderer ([link][2])
[3]. `FlatList numColumns={undefined}` Should not trigger Runtime Error NoSuchKey exception columnCount when enabling TalkBack. ([link][3])
[4]. TalkBack announces pages and cells with Nested Horizontal Flatlist in the rn-tester app ([link][4])

[1]: https://github.com/fabriziobertoglio1987/react-native-notes/issues/6#issuecomment-1050452894
[2]: https://github.com/fabriziobertoglio1987/react-native-notes/issues/6#issuecomment-1050462465
[3]: https://github.com/fabriziobertoglio1987/react-native-notes/issues/6#issuecomment-1032340879
[4]: https://github.com/fabriziobertoglio1987/react-native-notes/issues/6#issuecomment-1050618308
[10]:https://github.com/aosp-mirror/platform_frameworks_base/blob/1ac46f932ef88a8f96d652580d8105e361ffc842/core/java/android/widget/AdapterView.java#L1027-L1029 "GridView.java method responsible for calling setFromIndex and setToIndex"
[11]:https://github.com/fabriziobertoglio1987/react-native-notes/issues/6#issuecomment-1042518901 "test case on Android GridView"
[12]:https://github.com/fabriziobertoglio1987/react-native-notes/issues/6#issuecomment-1050452894 "TalkBack announces pages and cells with Horizontal Flatlist in the Paper Renderer"
[13]:https://github.com/intergalacticspacehighway "github intergalacticspacehighway"
[14]:https://github.com/fabriziobertoglio1987/react-native/blob/80acf523a4410adac8005d5c9472fb87f78e12ee/Libraries/Lists/FlatList.js#L617-L636 "FlatList accessibilityCollectionItem"
[16]:https://github.com/fabriziobertoglio1987/react-native/blob/5706bd7d3ee35dca48f85322a2bdcaec0bce2c85/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactScrollView.java#L183-L184 "logic added to ReactScrollView.java"
[17]: https://github.com/facebook/react-native/issues/30977
[18]: https://github.com/fabriziobertoglio1987/react-native-notes/issues/6
[19]: https://github.com/facebook/react-native/pull/31666
[20]: https://reactnative.dev/docs/next/flatlist#required-renderitem "FlatList renderItem documentation"
[21]: https://github.com/fabriziobertoglio1987/react-native/commit/75147359c5d070406ebbe488c57c3cd94c08c19d "commit that introduces fourth param accessibilityCollectionItem in callback renderItem"
[22]: https://github.com/facebook/react-native/pull/33180#discussion_r826748664 "discussion on the additional container View around each FlatList cell"
[23]: https://github.com/fabriziobertoglio1987/react-native/commit/d50fd1a68112f40f4be3ac3aa4d67f96df33e387 "commit adding prop getCellsInItemCount to VirtualizedList"

Reviewed By: kacieb

Differential Revision: D34518929

Pulled By: blavalla

fbshipit-source-id: 410a05263a56162bf505a4cad957b24005ed65ed
2022-04-19 19:45:10 -07:00

91 lines
1.8 KiB
JavaScript

/**
* Copyright (c) Meta Platforms, Inc. and affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @format
* @flow strict-local
*/
'use strict';
import type {SyntheticEvent} from '../../Types/CoreEventTypes';
// This must be kept in sync with the AccessibilityRolesMask in RCTViewManager.m
export type AccessibilityRole =
| 'none'
| 'button'
| 'togglebutton'
| 'link'
| 'search'
| 'image'
| 'keyboardkey'
| 'text'
| 'adjustable'
| 'imagebutton'
| 'header'
| 'summary'
| 'alert'
| 'checkbox'
| 'combobox'
| 'menu'
| 'menubar'
| 'menuitem'
| 'progressbar'
| 'radio'
| 'radiogroup'
| 'scrollbar'
| 'spinbutton'
| 'switch'
| 'tab'
| 'tabbar'
| 'tablist'
| 'timer'
| 'list'
| 'grid'
| 'toolbar';
// the info associated with an accessibility action
export type AccessibilityActionInfo = $ReadOnly<{
name: string,
label?: string,
...
}>;
// The info included in the event sent to onAccessibilityAction
export type AccessibilityActionEvent = SyntheticEvent<
$ReadOnly<{actionName: string, ...}>,
>;
export type AccessibilityState = {
disabled?: boolean,
selected?: boolean,
checked?: ?boolean | 'mixed',
busy?: boolean,
expanded?: boolean,
...
};
export type AccessibilityValue = $ReadOnly<{|
/**
* The minimum value of this component's range. (should be an integer)
*/
min?: number,
/**
* The maximum value of this component's range. (should be an integer)
*/
max?: number,
/**
* The current value of this component's range. (should be an integer)
*/
now?: number,
/**
* A textual description of this component's value. (will override minimum, current, and maximum if set)
*/
text?: Stringish,
|}>;