squiggle/packages/components/src/lib/hooks/useMaybeControlledValue.ts
2022-07-27 12:12:03 +04:00

23 lines
567 B
TypeScript

import { useState } from "react";
type ControlledValueArgs<T> = {
value?: T;
defaultValue: T;
onChange?: (x: T) => void;
};
export function useMaybeControlledValue<T>(
args: ControlledValueArgs<T>
): [T, (x: T) => void] {
let [uncontrolledValue, setUncontrolledValue] = useState(args.defaultValue);
let value = args.value ?? uncontrolledValue;
let onChange = (newValue: T) => {
if (args.value === undefined) {
// uncontrolled mode
setUncontrolledValue(newValue);
}
args.onChange?.(newValue);
};
return [value, onChange];
}