Files
standardnotes-app-web/packages/web/src/javascripts/Hooks/useListKeyboardNavigation.ts

91 lines
2.7 KiB
TypeScript

import { KeyboardKey } from '@standardnotes/ui-services'
import { FOCUSABLE_BUT_NOT_TABBABLE } from '@/Constants/Constants'
import { useCallback, useEffect, RefObject, useRef } from 'react'
export const useListKeyboardNavigation = (
container: RefObject<HTMLElement | null>,
initialFocus = 0,
shouldAutoFocus = false,
) => {
const listItems = useRef<HTMLButtonElement[]>([])
const focusedItemIndex = useRef<number>(initialFocus)
const focusItemWithIndex = useCallback((index: number, items?: HTMLButtonElement[]) => {
focusedItemIndex.current = index
if (items && items.length > 0) {
items[index]?.focus()
} else {
listItems.current[index]?.focus()
}
}, [])
useEffect(() => {
if (container.current) {
container.current.tabIndex = FOCUSABLE_BUT_NOT_TABBABLE
listItems.current = Array.from(container.current.querySelectorAll('button'))
}
}, [container])
const keyDownHandler = useCallback(
(e: KeyboardEvent) => {
if (e.key === KeyboardKey.Up || e.key === KeyboardKey.Down) {
e.preventDefault()
} else {
return
}
listItems.current = Array.from(container.current?.querySelectorAll('button') as NodeListOf<HTMLButtonElement>)
if (e.key === KeyboardKey.Up) {
let previousIndex = focusedItemIndex.current - 1
if (previousIndex < 0) {
previousIndex = listItems.current.length - 1
}
focusItemWithIndex(previousIndex)
}
if (e.key === KeyboardKey.Down) {
let nextIndex = focusedItemIndex.current + 1
if (nextIndex > listItems.current.length - 1) {
nextIndex = 0
}
focusItemWithIndex(nextIndex)
}
},
[container, focusItemWithIndex],
)
const FIRST_ITEM_FOCUS_TIMEOUT = 20
const containerFocusHandler = useCallback(() => {
const items = Array.from(container.current?.querySelectorAll('button') as NodeListOf<HTMLButtonElement>)
listItems.current = items
if (items.length < 1) {
return
}
const selectedItemIndex = Array.from(items).findIndex((item) => item.dataset.selected)
const indexToFocus = selectedItemIndex > -1 ? selectedItemIndex : initialFocus
setTimeout(() => {
focusItemWithIndex(indexToFocus, items)
}, FIRST_ITEM_FOCUS_TIMEOUT)
}, [container, focusItemWithIndex, initialFocus])
useEffect(() => {
if (shouldAutoFocus) {
containerFocusHandler()
}
}, [containerFocusHandler, shouldAutoFocus])
useEffect(() => {
const containerElement = container.current
containerElement?.addEventListener('keydown', keyDownHandler)
return () => {
containerElement?.removeEventListener('keydown', keyDownHandler)
}
}, [container, containerFocusHandler, keyDownHandler])
}