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fix: remove forwardref from useImperativeHandle docs
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@SebassNoob
SebassNoob committed Dec 12, 2024
1 parent 3b02f82 commit 1416468
Showing 1 changed file with 33 additions and 28 deletions.
61 changes: 33 additions & 28 deletions src/content/reference/react/useImperativeHandle.md
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Expand Up @@ -23,9 +23,9 @@ useImperativeHandle(ref, createHandle, dependencies?)
Call `useImperativeHandle` at the top level of your component to customize the ref handle it exposes:
```js
import { forwardRef, useImperativeHandle } from 'react';
import { useImperativeHandle } from 'react';

const MyInput = forwardRef(function MyInput(props, ref) {
function MyInput({ ref, ...props }) {
useImperativeHandle(ref, () => {
return {
// ... your methods ...
Expand All @@ -38,12 +38,19 @@ const MyInput = forwardRef(function MyInput(props, ref) {
#### Parameters {/*parameters*/}
* `ref`: The `ref` you received as the second argument from the [`forwardRef` render function.](/reference/react/forwardRef#render-function)
* `ref`: The `ref` you received as a prop to the `MyInput` component.
* `createHandle`: A function that takes no arguments and returns the ref handle you want to expose. That ref handle can have any type. Usually, you will return an object with the methods you want to expose.
* **optional** `dependencies`: The list of all reactive values referenced inside of the `createHandle` code. Reactive values include props, state, and all the variables and functions declared directly inside your component body. If your linter is [configured for React](/learn/editor-setup#linting), it will verify that every reactive value is correctly specified as a dependency. The list of dependencies must have a constant number of items and be written inline like `[dep1, dep2, dep3]`. React will compare each dependency with its previous value using the [`Object.is`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is) comparison. If a re-render resulted in a change to some dependency, or if you omitted this argument, your `createHandle` function will re-execute, and the newly created handle will be assigned to the ref.
<Note>
In versions prior to React 19, components by default don't expose their DOM nodes to parent components. This was done by opting in with [`forwardRef`](/reference/react/forwardRef) for the parent component to [have access](/learn/manipulating-the-dom-with-refs) to the child's DOM node.
`forwardRef` is now depreciated. Read the blog on [`ref` as a prop](/blog/2024/12/05/react-19#ref-as-a-prop) to learn more.
</Note>
#### Returns {/*returns*/}
`useImperativeHandle` returns `undefined`.
Expand All @@ -54,40 +61,38 @@ const MyInput = forwardRef(function MyInput(props, ref) {
### Exposing a custom ref handle to the parent component {/*exposing-a-custom-ref-handle-to-the-parent-component*/}
By default, components don't expose their DOM nodes to parent components. For example, if you want the parent component of `MyInput` to [have access](/learn/manipulating-the-dom-with-refs) to the `<input>` DOM node, you have to opt in with [`forwardRef`:](/reference/react/forwardRef)
To expose a DOM node to the parent element, pass in the `ref` prop to the node.
```js {4}
import { forwardRef } from 'react';

const MyInput = forwardRef(function MyInput(props, ref) {
```js {2}
function MyInput({ ref, ...props }) {
return <input {...props} ref={ref} />;
});
};
```
With the code above, [a ref to `MyInput` will receive the `<input>` DOM node.](/reference/react/forwardRef#exposing-a-dom-node-to-the-parent-component) However, you can expose a custom value instead. To customize the exposed handle, call `useImperativeHandle` at the top level of your component:
With the code above, [a ref to `MyInput` will receive the `<input>` DOM node.](/learn/manipulating-the-dom-with-refs) However, you can expose a custom value instead. To customize the exposed handle, call `useImperativeHandle` at the top level of your component:
```js {4-8}
import { forwardRef, useImperativeHandle } from 'react';
import { useImperativeHandle } from 'react';

const MyInput = forwardRef(function MyInput(props, ref) {
function MyInput({ ref, ...props }) {
useImperativeHandle(ref, () => {
return {
// ... your methods ...
};
}, []);

return <input {...props} />;
});
};
```
Note that in the code above, the `ref` is no longer forwarded to the `<input>`.
For example, suppose you don't want to expose the entire `<input>` DOM node, but you want to expose two of its methods: `focus` and `scrollIntoView`. To do this, keep the real browser DOM in a separate ref. Then use `useImperativeHandle` to expose a handle with only the methods that you want the parent component to call:
```js {7-14}
import { forwardRef, useRef, useImperativeHandle } from 'react';
import { useRef, useImperativeHandle } from 'react';

const MyInput = forwardRef(function MyInput(props, ref) {
function MyInput({ ref, ...props }) {
const inputRef = useRef(null);

useImperativeHandle(ref, () => {
Expand All @@ -102,7 +107,7 @@ const MyInput = forwardRef(function MyInput(props, ref) {
}, []);

return <input {...props} ref={inputRef} />;
});
};
```
Now, if the parent component gets a ref to `MyInput`, it will be able to call the `focus` and `scrollIntoView` methods on it. However, it will not have full access to the underlying `<input>` DOM node.
Expand Down Expand Up @@ -134,9 +139,9 @@ export default function Form() {
```
```js src/MyInput.js
import { forwardRef, useRef, useImperativeHandle } from 'react';
import { useRef, useImperativeHandle } from 'react';

const MyInput = forwardRef(function MyInput(props, ref) {
function MyInput({ ref, ...props }) {
const inputRef = useRef(null);

useImperativeHandle(ref, () => {
Expand All @@ -151,7 +156,7 @@ const MyInput = forwardRef(function MyInput(props, ref) {
}, []);

return <input {...props} ref={inputRef} />;
});
};

export default MyInput;
```
Expand Down Expand Up @@ -195,11 +200,11 @@ export default function Page() {
```
```js src/Post.js
import { forwardRef, useRef, useImperativeHandle } from 'react';
import { useRef, useImperativeHandle } from 'react';
import CommentList from './CommentList.js';
import AddComment from './AddComment.js';

const Post = forwardRef((props, ref) => {
function Post({ ref, ...props }) {
const commentsRef = useRef(null);
const addCommentRef = useRef(null);

Expand All @@ -221,16 +226,16 @@ const Post = forwardRef((props, ref) => {
<AddComment ref={addCommentRef} />
</>
);
});
};

export default Post;
```
```js src/CommentList.js
import { forwardRef, useRef, useImperativeHandle } from 'react';
import { useRef, useImperativeHandle } from 'react';

const CommentList = forwardRef(function CommentList(props, ref) {
function CommentList({ ref, ...props }) {
const divRef = useRef(null);

useImperativeHandle(ref, () => {
Expand All @@ -252,17 +257,17 @@ const CommentList = forwardRef(function CommentList(props, ref) {
{comments}
</div>
);
});
}

export default CommentList;
```
```js src/AddComment.js
import { forwardRef, useRef, useImperativeHandle } from 'react';
import { useRef, useImperativeHandle } from 'react';

const AddComment = forwardRef(function AddComment(props, ref) {
function AddComment({ ref, ...props }) {
return <input placeholder="Add comment..." ref={ref} />;
});
}

export default AddComment;
```
Expand Down

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