element-call-Github/src/useCallViewKeyboardShortcuts.ts
Robin 380f49fccc Improve accessibility of keyboard shortcuts
Ensure that they don't interfere with say, using spacebar to press a button, and also ensure that they won't do surprising things like scroll the page at the same time.
2024-07-24 18:42:21 -04:00

104 lines
3.0 KiB
TypeScript

/*
Copyright 2022-2023 New Vector Ltd
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
import { RefObject, useCallback, useMemo, useRef } from "react";
import { useEventTarget } from "./useEvents";
/**
* Determines whether focus is in the same part of the tree as the given
* element (specifically, if the element or an ancestor of it is focused).
*/
const mayReceiveKeyEvents = (e: HTMLElement): boolean => {
const focusedElement = document.activeElement;
return focusedElement !== null && focusedElement.contains(e);
};
export function useCallViewKeyboardShortcuts(
focusElement: RefObject<HTMLElement | null>,
toggleMicrophoneMuted: () => void,
toggleLocalVideoMuted: () => void,
setMicrophoneMuted: (muted: boolean) => void,
): void {
const spacebarHeld = useRef(false);
// These event handlers are set on the window because we want users to be able
// to trigger them without going to the trouble of focusing something
useEventTarget(
window,
"keydown",
useCallback(
(event: KeyboardEvent) => {
if (focusElement.current === null) return;
if (!mayReceiveKeyEvents(focusElement.current)) return;
if (event.key === "m") {
event.preventDefault();
toggleMicrophoneMuted();
} else if (event.key == "v") {
event.preventDefault();
toggleLocalVideoMuted();
} else if (event.key === " ") {
event.preventDefault();
if (!spacebarHeld.current) {
spacebarHeld.current = true;
setMicrophoneMuted(false);
}
}
},
[
focusElement,
toggleLocalVideoMuted,
toggleMicrophoneMuted,
setMicrophoneMuted,
],
),
// Because this is set on the window, to prevent shortcuts from activating
// another event callback at the same time, we need to preventDefault
// *before* child elements receive the event by using capture mode
useMemo(() => ({ capture: true }), []),
);
useEventTarget(
window,
"keyup",
useCallback(
(event: KeyboardEvent) => {
if (focusElement.current === null) return;
if (!mayReceiveKeyEvents(focusElement.current)) return;
if (event.key === " ") {
spacebarHeld.current = false;
setMicrophoneMuted(true);
}
},
[focusElement, setMicrophoneMuted],
),
);
useEventTarget(
window,
"blur",
useCallback(() => {
if (spacebarHeld.current) {
spacebarHeld.current = false;
setMicrophoneMuted(true);
}
}, [setMicrophoneMuted, spacebarHeld]),
);
}