ArturKalach / react-native-a11y

A11y Library for RN
MIT License
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React Native A11y

This is a React Native A11y Library with following main features

iOS reader Android reader
iOS Keyboard Android Keyboard

A11y is important, there are a lot of reasons to support and be compliant with it. First of all, it helps people with disabilities work and use your application easily and live a better life. Banks, medication, shops, and delivery is a small list of what people are usually interested in, and it can be more important for people with limitations.

There are can be other reasons, customer requirements, laws and requirements for specific groups of apps, remote control, etc. Based on this you can find a lot of advantages and benefits to supporting A11y.

Installation

This library is not finished yer and currently on beta stage. We will be glad to issues, questions, and help.

  1. Download package with npm or yarn
npm i react-native-a11y
yarn add react-native-a11y
  1. Install pods cd ios && pod install

  2. iOS only

    NOTE: If you don't plan to use the isKeyboardConnected or keyboardStatusListener functionality, you can skip this step. Linking the GameController framework is optional but required for the proper functioning of isKeyboardConnected and keyboardStatusListener.

Link keyboard(Game) binary with libraries

Xcode screenshot
Why linking is needed Unfortunately, the GameController framework is the only viable solution to obtain information about the keyboard and its connection. While there are other potential solutions, they are mostly workarounds and could be rejected by the App Store review process.
  1. Add provider to root of your app:
watch: examples/A11ySample/App.tsx

export const App = () => {
  return (
    <A11yProvider>
        // content here
    </A11yProvider>
  );
};

Usage

A11y library consists of different components and hooks, to start work with react-native-a11y you can get familiar with an example app in examples/A11ySample.

A11yModule

The core of the library is A11yModule, A11yModule provides additional functions to work with a11y such as order, reader focus, keyboard focus, announcements, etc

Function Description Interface
isA11yReaderEnabled return promise with status of a11y reader (TalkBack or VoiceOver) true(enabled)/false(disabled) () => Promise<boolean>
isKeyboardConnected return promise with status of keyboard connection, true(connected)/false(disconnected) () => Promise<boolean>
a11yStatusListener listener for a11y reader status ((e: { status: boolean }) => void) => void;
keyboardStatusListener listener for keyboard connection status ((e: { status: boolean }) => void) => void;
announceForAccessibility Post a string to be announced by the screen reader. Android default, ios specific. (announcement: string) => void;
announceScreenChange Announces new screen name. (announcement: string) => void;
setA11yFocus Set a11y reader focus to the component (ref: React.RefObject<React.Component>) => void;
setKeyboardFocus Set keyboard focus to the component (ref: React.RefObject<React.Component>) => void;
setPreferredKeyboardFocus iOS only, set redirection of keyboard from one component to another one (nativeTag: number, nextTag: number) => void;
focusFirstInteractiveElement Focus first interactive element on a screen (ref: React.RefObject<React.Component>) => void;
setA11yElementsOrder Set a11y reader focus order setA11yElementsOrder: <T>(info: { tag?: RefObject<T>; views: T[]; }) => void;

setA11yFocus and setKeyboardFocus works similar to AccessibilityInfo.setAccessibilityFocus, difference is they request refs instead of tags and you don't need use findNodeHandle.

Examples

setA11yFocus

watch: examples/A11ySample/src/screens/ReaderFocusScreen

import { A11yModule } from "react-native-a11y";
...

const App = () => {
  const ref1 = useRef(null);
  const ref3 = useRef(null);
...

return (
 ...
 <Button
    ref={ref1}
    onPress={() => A11yModule.setA11yFocus(ref3)}
    title="1. Set focus to third"
 />
 ...
  <Button
    ref={ref3}
    onPress={() => A11yModule.setA11yFocus(ref2)}
    title="3. Set focus to second"
  />
}

setKeyboardFocus

watch: examples/A11ySample/src/screens/KeyboardFocusScreen

import { A11yModule, KeyboardProvider } from "react-native-a11y";
...

const App = () => {
  const ref1 = useRef(null);
  const ref3 = useRef(null);
...

return (
 ...
 <Button
    ref={ref1}
    onPress={() => A11yModule.setKeyboardFocus(ref3)}
    title="1. Set focus to third"
 />
 ...
  <Button
    ref={ref3}
    onPress={() => A11yModule.setKeyboardFocus(ref2)}
    title="3. Set focus to second"
  />
}

You can but not really need to use A11yModule.setA11yElementsOrder directly, we have specific useful hooks to work with order.

useFocusOrder and useDynamicFocusOrder

To set an order for components we have useFocusOrder, useDynamicFocusOrder

A11yModule.setA11yElementsOrder is a more direct one we just pass refs to components and set order, but there are a lot of questions about when to call and set order. To make a better experience two similar hooks were created useFocusOrder and useDynamicFocusOrder

useDynamicFocusOrder

useDynamicFocusOrder returns target ref, trigger function, and function to register your components.

export type UseDynamicFocusOrder = () => {
  a11yOrder: {
    ref: RefObject<View>; /// target ref, we need a target ref to a container View
    onLayout: () => void; // trigger, we use onLayout to realize when components are appear on a screen, useEffect and useLayoutEffect don't work properly
  };
  registerOrder: (order: number) => (ref: View) => void; // function to set order
  reset: () => void; // clear function
};
soon

useFocusOrder

useFocusOrder is based on useDynamicFocusOrder but more static and predictable.

(size: number) // count of refs
    => FocusOrderInfo<T> = {
  a11yOrder: {
    ref: RefObject<T>; // target ref, we need a target ref to a container View
    onLayout: () => void; // trigger, we use onLayout to realize when components are appear on a screen, useEffect and useLayoutEffect don't work properly
  };
  refs: ((ref: T | null) => void)[]; // array of callback refs to use for order
  reset: () => void; // clear function
};
watch: examples/A11ySample/src/screens/A11yOrderScreen

import { A11yOrder, useFocusOrder } from "react-native-a11y";

const App = () => {
    const { a11yOrder, refs } = useFocusOrder(3); // 3 number of wanted refs
    ...
    return (
        <A11yOrder onLayout={onLayoutHandler} a11yOrder=  {a11yOrder}>
            <Text style={styles.font} ref={refs[0]}>
                First
            </Text>
            <Text style={styles.font} ref={refs[2]}>
                Third
            </Text>
            <Text style={styles.font} ref={refs[1]}>
                Second
            </Text>
        </A11yOrder>
    )

The code in example set a new order for components, instead of a direct one it will follow 1 -> 3 -> 2

You also can find a new A11yOrder component it's just shorts for <View {...a11yOrder} />

KeyboardFocusView

KeyboardFocusView is view based component, has additional props and provide possibility to make component focusable by a keyboard. Additionally, you can handle pressing events from keyboard. This system can help to handle Enter press or long press on spacebar.

Props Description
onFocusChange? Event to handle focus change, (e: event.nativeEvent.isFocused) => void
canBeFocused? boolean default true, describe whether component can be focused by keyboard
onKeyDownPress? Event to handle a keyboard key down event, (e: OnKeyPress) => void
onKeyUpPress? Event to handle a keyboard key up event(e: OnKeyPress) => void

Where OnKeyPress is:

type OnKeyPress = NativeSyntheticEvent<{
  keyCode: number;
  unicode: number;
  unicodeChar: string;
  isLongPress: boolean;
  isAltPressed: boolean;
  isShiftPressed: boolean;
  isCtrlPressed: boolean;
  isCapsLockOn: boolean;
  hasNoModifiers: boolean;
}>;

Note:

Latest iOS versions has a Commands for a11y support, which override keyboard key presses. If you open Accessibility -> Keyboards -> Full Keyboard Access -> Commands, you can find that Spacebar key id assigned to the Activate command. Because of this, all your spacebar presses will be ignored.

Examples

import { KeyboardFocusView } "react-native-a11y";

const App = () => {

  return <KeyboardFocusView>
    <Text>Focusable</Text>
  </KeyboardFocusView>
}

Pressable

Almost original pressable, but used KeyboardFocusView instead of View

Provides additional functionality for usual Pressable

Props Description
onFocusChange? Event to handle focus change, (e: event.nativeEvent.isFocused) => void
canBeFocused? boolean default true, describe whether component can be focused by keyboard

Examples

watch: examples/A11ySample/src/components/Button

import React, { useState } from "react";
import { StyleSheet, Text, View, ViewStyle } from "react-native";
import { Pressable, FocusStyle, OnFocusChangeFn } from "react-native-a11y";

export const Button = React.forwardRef<View, Props>(
  ({ title, onPress, style, focusStyle, canBeFocused = true }, ref) => {
    ...

    const [focused, setFocusStatus] = useState(false);

    const onFocusChangeHandler: OnFocusChangeFn = event => {
      setFocusStatus(event.nativeEvent.isFocused);
    };

    return (
      <View style={style}>
        <Pressable
          onFocusChange={onFocusChangeHandler}
          canBeFocused={canBeFocused}
          onPress={onPress}
          style={[styles.container]}
          focusStyle={focusStyle || fStyle}
          ref={ref}
        >
          <Text style={[styles.font, focused && styles.focusedFont]}>
            {title}
          </Text>
        </Pressable>
      </View>
    );
  },
);

KeyboardFocusTextInput

KeyboardFocusTextInput is a TextInput with a view-based wrapper (TextInputWrapperNative). This wrapper helps standardize TextInput focusing behavior and also serves as a workaround for the Tab/Shift+Tab issue in Android.

Props Description
TextInputProps Default TextInput props that are passed to the TextInput
onFocusChange? Event to handle focus change, (e: event.nativeEvent.isFocused) => void
canBeFocused? boolean default true, describe whether component can be focused by keyboard
focusType?: Focus type can be default, auto, or press. Based on investigation, Android and iOS typically have different default behaviors. On Android, the TextInput is focused by default, while on iOS, you need to press to focus. auto is used for automatic focusing, while keyboard focus targets the input. With press, you need to press the spacebar to focus an input.
blurType?: Only for iOS. This defines the behavior for blurring input when focus moves away from the component. By default, iOS allows typing when the keyboard focus is on another component. You can use disable to blur input when focus moves away. (Further investigation is needed for Android.)
containerStyle?: Style property (StyleProp) for wrapper view

Examples

import { KeyboardFocusTextInput } "react-native-a11y";

const App = () => {

  return  <KeyboardFocusTextInput
      style={styles.textInput}
      containerStyle={styles.textInputContainer}
      value={inputValue}
      onChangeText={setInputValue}
      focusType="auto"
      blurType="auto"
    />
}

KeyboardProvider

Specific provider, used to block all focusable views (KeyboardFocusView). Based on value props disable or not KeyboardFocusView. It can be useful to block list of components, on screen for example or on Drawer in React Navigation.

watch: examples/A11ySample/src/screens/KeyboardFocusScreen

const App = () => {
  return <>
     <Button
        style={styles.btn}
        title="Title"
      />
      <KeyboardProvider value={false}>
        <Button title="Disabled focus" />
        <Button title="Disabled focus" />
      </KeyboardProvider>
  </>
}

Roadmap

ReactNative old versions supporting

The library provides default support for RN versions starting from v0.66.1 and up to v0.72.*.

To enable support for versions 0.64. and 0.65., add legacyVer=true in your gradle.properties file

// root/android/gradle.properties

legacyVer=true

If for some reason you need support for older versions, feel free to create an issue.

Problems

iOS

Android

Contributing

Any type of contribution is highly appreciated. Feel free to create PRs, raise issues, or share ideas.

Acknowledgements

I really appreciate the work and solutions provided by Andrii Koval, Michail Chavkin, Dzmitry Khamitsevich. I think there was not this library without them, I also want to thank Aliaksei Kisel and Herman Tseranevich for help with publishing and reviewing.

Many thanks to the contributors: Boaz Poolman, YOEL311 Yoel Naki

And of course, thanks to the issue reporters: Leonardo Guarnieri de Bastiani, David, Summer Knight,Rick Vellinga, joonmanji

License

MIT


Made with create-react-native-library