NextJS 動態導入問題

Question

從NextJS dynamic導入時，我遇到了一個非常奇怪的問題。

我正在導入這樣的組件：

const Spinner = dynamic(() => import('components/ui/Spinner').then(mod => mod.Spinner))

Spinner.tsx是

import {useEffect, useState} from 'react'
import PulseLoader from 'react-spinners/PulseLoader'

import {FadeHOC} from '.'
import theme from 'utils/theme'


interface Props {
  inline?: boolean
}

const TIMEOUT = 1000

export const Spinner = ({inline}: Props) => {

  const [show, setShow] = useState(false)

  useEffect(() => {
    
    const timeout = setTimeout(
      () => setShow(true),
      TIMEOUT
    )
    
    return () => clearTimeout(timeout)
  }, [])

  return (
    show
      ? <FadeHOC>
          <PulseLoader size={10} margin={3} color={theme.color} css={inline ? 'margin-left: 14px;' : 'display: block; text-align: center; margin: 100px auto;'} />
        </FadeHOC>
      : null
  )
}

在dynamic導入語句中，我收到了TypeScript投訴：

Argument of type '() => Promise<(({ inline }: Props) => JSX.Element) | ComponentClass<never, any> | FunctionComponent<never> | { default: ComponentType<never>; }>' is not assignable to parameter of type 'DynamicOptions<{}> | Loader<{}>'.
  Type '() => Promise<(({ inline }: Props) => JSX.Element) | ComponentClass<never, any> | FunctionComponent<never> | { default: ComponentType<never>; }>' is not assignable to type '() => LoaderComponent<{}>'.
    Type 'Promise<(({ inline }: Props) => Element) | ComponentClass<never, any> | FunctionComponent<never> | { default: ComponentType<never>; }>' is not assignable to type 'LoaderComponent<{}>'.
      Type '(({ inline }: Props) => Element) | ComponentClass<never, any> | FunctionComponent<never> | { default: ComponentType<never>; }' is not assignable to type 'ComponentType<{}> | { default: ComponentType<{}>; }'.
        Type '({ inline }: Props) => JSX.Element' is not assignable to type 'ComponentType<{}> | { default: ComponentType<{}>; }'.
          Type '({ inline }: Props) => JSX.Element' is not assignable to type 'FunctionComponent<{}>'.
            Types of parameters '__0' and 'props' are incompatible.
              Type '{ children?: ReactNode; }' has no properties in common with type 'Props'.ts(2345)

我不知道投訴的內容是什么，非常感謝任何幫助！

Answer 1

dynamic類型如下：

export default function dynamic<P = {}>(dynamicOptions: DynamicOptions<P> | Loader<P>, options?: DynamicOptions<P>): React.ComponentType<P>;

其中 P 是導入組件的道具

因此，動態期望得到Loader<P> = LoaderComponent<P> = Promise<React.ComponentType<P>

你只需要告訴他道具是什么。 像這樣：

const Spinner = dynamic<{ inline?: boolean }>(
  () => import('components/ui/Spinner').then(mod => mod.Spinner)
)

或者

import { Spinner as StaticSpinner } from 'components/ui/Spinner'

const Spinner = dynamic<React.ComponentProps<typeof StaticSpinner>>(
  () => import('components/ui/Spinner').then(mod => mod.Spinner)
)

或將 Props 導出，然后：

import { Props as SpinnerProps } from 'components/ui/Spinner'

const Spinner = dynamic<SpinnerProps>(
  () => import('components/ui/Spinner').then(mod => mod.Spinner)
)

Answer 2

@brc-dd 是對的，雖然很少解釋為什么它會這樣工作：

dynamic類型如下：

export default function dynamic<P = {}>(dynamicOptions: DynamicOptions<P> | Loader<P>, options?: DynamicOptions<P>): React.ComponentType<P>;

所以它希望你返回React.ComponentType<P>這意味着：

type ComponentType<P = {}> = ComponentClass<P> | FunctionComponent<P>;

FunctionComponent是：

interface FunctionComponent<P = {}> {
        (props: PropsWithChildren<P>, context?: any): ReactElement<any, any> | null;
        propTypes?: WeakValidationMap<P>;
        contextTypes?: ValidationMap<any>;
        defaultProps?: Partial<P>;
        displayName?: string;
    }

所以你必須有children鑰匙的道具。 如果你不想弄亂你的組件界面並且它實際上不接受孩子那么你可以輸入children?: never; 在組件 Props 接口中。