@restart/hooks
Version:
A set of utility and general-purpose React hooks.
59 lines (57 loc) • 1.61 kB
JavaScript
exports.__esModule = true;
exports.default = exports.ObservableMap = void 0;
var _useForceUpdate = _interopRequireDefault(require("./useForceUpdate.js"));
var _useStableMemo = _interopRequireDefault(require("./useStableMemo.js"));
function _interopRequireDefault(e) { return e && e.__esModule ? e : { default: e }; }
class ObservableMap extends Map {
constructor(listener, init) {
super(init);
this.listener = listener;
}
set(key, value) {
super.set(key, value);
// When initializing the Map, the base Map calls this.set() before the
// listener is assigned so it will be undefined
if (this.listener) this.listener(this);
return this;
}
delete(key) {
let result = super.delete(key);
this.listener(this);
return result;
}
clear() {
super.clear();
this.listener(this);
}
}
/**
* Create and return a [Map](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map) that triggers rerenders when it's updated.
*
* ```tsx
* const customerAges = useMap<number>([
* ['john', 24],
* ['betsy', 25]
* ]);
*
* return (
* <>
* {Array.from(ids, ([name, age]) => (
* <div>
* {name}: {age}. <button onClick={() => ids.delete(name)}>X</button>
* </div>
* )}
* </>
* )
* ```
*
* @param init initial Map entries
*/
exports.ObservableMap = ObservableMap;
function useMap(init) {
const forceUpdate = (0, _useForceUpdate.default)();
return (0, _useStableMemo.default)(() => new ObservableMap(forceUpdate, init), []);
}
var _default = useMap;
exports.default = _default;
;