28 lines
700 B
TypeScript
28 lines
700 B
TypeScript
// Copyright 2017-2021 @polkadot/react-hooks authors & contributors
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// SPDX-License-Identifier: Apache-2.0
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import { useMemo, useState } from 'react';
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import { isUndefined } from '@polkadot/util';
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export type FormField<T> = [
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T | null,
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boolean,
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(_?: T | null) => void
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];
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export function useFormField<T> (defaultValue: T | null, validate: (_: T) => boolean = (): boolean => true): FormField<T> {
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const [value, setValue] = useState<T | null>(defaultValue);
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const isValid = useMemo(
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(): boolean => !!value && validate(value),
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[validate, value]
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);
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const setter = (value?: T | null) => !isUndefined(value) && setValue(value);
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return [
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value,
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isValid,
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setter
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];
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}
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