mirror of
https://github.com/element-hq/element-web.git
synced 2024-12-15 21:11:32 +03:00
41 lines
1.4 KiB
TypeScript
41 lines
1.4 KiB
TypeScript
|
/*
|
||
|
|
Copyright 2020 The Matrix.org Foundation C.I.C.
|
||
|
|
|
||
|
|
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 {useEffect, useRef} from "react";
|
||
|
|
|
||
|
|
import {ActionPayload} from "../dispatcher/payloads";
|
||
|
|
import {Dispatcher} from "flux";
|
||
|
|
|
||
|
|
// Hook to simplify listening to flux dispatches
|
||
|
|
export const useDispatcher = (dispatcher: Dispatcher<ActionPayload>, handler: (payload: ActionPayload) => void) => {
|
||
|
|
// Create a ref that stores handler
|
||
|
|
const savedHandler = useRef((payload: ActionPayload) => {});
|
||
|
|
|
||
|
|
// Update ref.current value if handler changes.
|
||
|
|
useEffect(() => {
|
||
|
|
savedHandler.current = handler;
|
||
|
|
}, [handler]);
|
||
|
|
|
||
|
|
useEffect(() => {
|
||
|
|
// Create event listener that calls handler function stored in ref
|
||
|
|
const ref = dispatcher.register((payload) => savedHandler.current(payload));
|
||
|
|
// Remove event listener on cleanup
|
||
|
|
return () => {
|
||
|
|
dispatcher.unregister(ref);
|
||
|
|
};
|
||
|
|
}, [dispatcher]);
|
||
|
|
};
|