Mirror: React hooks for accessible, common web interactions. UI super powers without the UI.
kitten.sh
1import { useRef } from 'react';
2import { useLayoutEffect } from './utils/react';
3import { contains } from './utils/element';
4import { makePriorityHook } from './usePriority';
5import { Ref } from './types';
6
7const usePriority = makePriorityHook();
8
9export interface DismissableOptions {
10 focusLoss?: boolean;
11 disabled?: boolean;
12}
13
14export function useDismissable<T extends HTMLElement>(
15 ref: Ref<T>,
16 onDismiss: () => void,
17 options?: DismissableOptions
18) {
19 const focusLoss = !!(options && options.focusLoss);
20 const disabled = !!(options && options.disabled);
21 const hasPriority = usePriority(ref, disabled);
22 const onDismissRef = useRef(onDismiss);
23
24 useLayoutEffect(() => {
25 onDismissRef.current = onDismiss;
26 }, [onDismiss]);
27
28 useLayoutEffect(() => {
29 const { current: element } = ref;
30 if (!element || disabled) return;
31
32 function onFocusOut(event: FocusEvent) {
33 if (event.defaultPrevented) return;
34
35 const { target, relatedTarget } = event;
36 if (contains(element, target) && !contains(element, relatedTarget)) {
37 onDismissRef.current();
38 }
39 }
40
41 function onKey(event: KeyboardEvent) {
42 if (!event.isComposing && event.code === 'Escape') {
43 // The current dialog can be dismissed by pressing escape if it either has focus
44 // or it has priority
45 const active = document.activeElement;
46 if (hasPriority || (active && contains(element, active))) {
47 event.preventDefault();
48 onDismissRef.current();
49 }
50 }
51 }
52
53 function onClick(event: MouseEvent | TouchEvent) {
54 const { target } = event;
55 if (contains(element, target) || event.defaultPrevented) {
56 return;
57 }
58
59 // The current dialog can be dismissed by pressing outside of it if it either has
60 // focus or it has priority
61 const active = document.activeElement;
62 if (hasPriority || (active && contains(element, active))) {
63 event.preventDefault();
64 onDismissRef.current();
65 }
66 }
67
68 if (focusLoss) document.body.addEventListener('focusout', onFocusOut);
69
70 document.addEventListener('mousedown', onClick);
71 document.addEventListener('touchstart', onClick);
72 document.addEventListener('keydown', onKey);
73
74 return () => {
75 if (focusLoss) document.body.removeEventListener('focusout', onFocusOut);
76
77 document.removeEventListener('mousedown', onClick);
78 document.removeEventListener('touchstart', onClick);
79 document.removeEventListener('keydown', onKey);
80 };
81 }, [ref.current, hasPriority, disabled, focusLoss]);
82}