/
focusManager.ts
90 lines (75 loc) 路 2.07 KB
/
focusManager.ts
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
import { Subscribable } from './subscribable'
import { isServer } from './utils'
type SetupFn = (
setFocused: (focused?: boolean) => void,
) => (() => void) | undefined
export class FocusManager extends Subscribable {
private focused?: boolean
private cleanup?: () => void
private setup: SetupFn
constructor() {
super()
this.setup = (onFocus) => {
// addEventListener does not exist in React Native, but window does
// eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
if (!isServer && window.addEventListener) {
const listener = () => onFocus()
// Listen to visibillitychange and focus
window.addEventListener('visibilitychange', listener, false)
window.addEventListener('focus', listener, false)
return () => {
// Be sure to unsubscribe if a new handler is set
window.removeEventListener('visibilitychange', listener)
window.removeEventListener('focus', listener)
}
}
return
}
}
protected onSubscribe(): void {
if (!this.cleanup) {
this.setEventListener(this.setup)
}
}
protected onUnsubscribe() {
if (!this.hasListeners()) {
this.cleanup?.()
this.cleanup = undefined
}
}
setEventListener(setup: SetupFn): void {
this.setup = setup
this.cleanup?.()
this.cleanup = setup((focused) => {
if (typeof focused === 'boolean') {
this.setFocused(focused)
} else {
this.onFocus()
}
})
}
setFocused(focused?: boolean): void {
this.focused = focused
if (focused) {
this.onFocus()
}
}
onFocus(): void {
this.listeners.forEach((listener) => {
listener()
})
}
isFocused(): boolean {
if (typeof this.focused === 'boolean') {
return this.focused
}
// document global can be unavailable in react native
if (typeof document === 'undefined') {
return true
}
return [undefined, 'visible', 'prerender'].includes(
document.visibilityState,
)
}
}
export const focusManager = new FocusManager()