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---
id: portals
title: Portals
permalink: docs/portals.html
---
Portals provide a first-class way to render children into a DOM node that exists outside the DOM hierarchy of the parent component.
```js
ReactDOM.createPortal(child, container)
```
The first argument (`child`) is any [renderable React child](/docs/react-component.html#render), such as an element, string, or fragment. The second argument (`container`) is a DOM element.
## Usage {#usage}
Normally, when you return an element from a component's render method, it's mounted into the DOM as a child of the nearest parent node:
```js{4,6}
render() {
// React mounts a new div and renders the children into it
return (
<div>
{this.props.children}
</div>
);
}
```
However, sometimes it's useful to insert a child into a different location in the DOM:
```js{6}
render() {
// React does *not* create a new div. It renders the children into `domNode`.
// `domNode` is any valid DOM node, regardless of its location in the DOM.
return ReactDOM.createPortal(
this.props.children,
domNode
);
}
```
A typical use case for portals is when a parent component has an `overflow: hidden` or `z-index` style, but you need the child to visually "break out" of its container. For example, dialogs, hovercards, and tooltips.
> Note:
>
> When working with portals, remember that [managing keyboard focus](/docs/accessibility.html#programmatically-managing-focus) becomes very important.
>
> For modal dialogs, ensure that everyone can interact with them by following the [WAI-ARIA Modal Authoring Practices](https://www.w3.org/WAI/ARIA/apg/patterns/dialogmodal/).
[**Try it on CodePen**](https://codepen.io/gaearon/pen/yzMaBd)
## Event Bubbling Through Portals {#event-bubbling-through-portals}
Even though a portal can be anywhere in the DOM tree, it behaves like a normal React child in every other way. Features like context work exactly the same regardless of whether the child is a portal, as the portal still exists in the *React tree* regardless of position in the *DOM tree*.
This includes event bubbling. An event fired from inside a portal will propagate to ancestors in the containing *React tree*, even if those elements are not ancestors in the *DOM tree*. Assuming the following HTML structure:
```html
<html>
<body>
<div id="app-root"></div>
<div id="modal-root"></div>
</body>
</html>
```
A `Parent` component in `#app-root` would be able to catch an uncaught, bubbling event from the sibling node `#modal-root`.
```js{28-31,42-49,53,61-63,70-71,74}
// These two containers are siblings in the DOM
const appRoot = document.getElementById('app-root');
const modalRoot = document.getElementById('modal-root');
class Modal extends React.Component {
constructor(props) {
super(props);
this.el = document.createElement('div');
}
componentDidMount() {
// The portal element is inserted in the DOM tree after
// the Modal's children are mounted, meaning that children
// will be mounted on a detached DOM node. If a child
// component requires to be attached to the DOM tree
// immediately when mounted, for example to measure a
// DOM node, or uses 'autoFocus' in a descendant, add
// state to Modal and only render the children when Modal
// is inserted in the DOM tree.
modalRoot.appendChild(this.el);
}
componentWillUnmount() {
modalRoot.removeChild(this.el);
}
render() {
return ReactDOM.createPortal(
this.props.children,
this.el
);
}
}
class Parent extends React.Component {
constructor(props) {
super(props);
this.state = {clicks: 0};
this.handleClick = this.handleClick.bind(this);
}
handleClick() {
// This will fire when the button in Child is clicked,
// updating Parent's state, even though button
// is not direct descendant in the DOM.
this.setState(state => ({
clicks: state.clicks + 1
}));
}
render() {
return (
<div onClick={this.handleClick}>
<p>Number of clicks: {this.state.clicks}</p>
<p>
Open up the browser DevTools
to observe that the button
is not a child of the div
with the onClick handler.
</p>
<Modal>
<Child />
</Modal>
</div>
);
}
}
function Child() {
// The click event on this button will bubble up to parent,
// because there is no 'onClick' attribute defined
return (
<div className="modal">
<button>Click</button>
</div>
);
}
React 18 (#4499) * [18] ReactDOM reference to createRoot/hydrateRoot (#4340) * [18] ReactDOM reference to createRoot/hydrateRoot * Update note about render and hydrate * Match the warning text * s/Render/render * [18] Update ReactDOMClient docs (#4468) * [18] Update ReactDOMClient docs * Remove ReactDOMClient where it&#39;s obvious * Update browser message * Update browser message note * Update based on feedback * Add react-dom/client docs * [18] Upgrade homepage examples (#4469) * [18] Switch code samples to createRoot (#4470) * [18] Switch code samples to createRoot * Feedback fixes * Feedback updates * [18] Use hydrateRoot and root.unmount. (#4473) * [18] Add docs for flushSync (#4474) * [18] Add flushSync to ReactDOM docs * Seb feedback * More Seb feedback * [18] Bump version to 18 (#4478) * [18] Update browser requirements (#4476) * [18] Update browser requirements * Update based on feedback * [18] Add stubs for new API references (#4477) * [18] Add stubs for new API references * Change order/grouping * [18] Redirect outdated Concurrent Mode docs (#4481) * [18] Redirect outdated Concurrent Mode docs * Use Vercel redirects instead * [18] Update versions page (#4482) * [18] Update version page * Fix prettier * [18] Update React.lazy docs (#4483) * [18] Add docs for useSyncExternalStore (#4487) * [18] Add docs for useSyncExternalStore * rm &#34;optional&#34; * [18] Add docs for useInsertionEffect (#4486) * [18] Add docs for useId (#4488) * [18] Add docs for useId * Update based on feedback * Add Strict Effects to Strict Mode (#4362) * Add Strict Effects to Strict Mode * Update with new thinking * [18] Update docs for useEffect timing (#4498) * [18] Add docs for useDeferredValue (#4497) * [18] Update suspense docs for unexpected fallbacks (#4500) * [18] Update suspense docs for unexpected fallbacks * Add inline code block * Feedback fixes * [18] Updated Suspense doc with behavior during SSR and Hydration (#4484) * update wording * wording * update events * Update content/docs/reference-react.md Co-authored-by: Sebastian Silbermann &lt;silbermann.sebastian@gmail.com&gt; * add link to selective hydration * remove some of the implementation details Co-authored-by: Sebastian Silbermann &lt;silbermann.sebastian@gmail.com&gt; * [18] renderToPipeableStream doc (#4485) * new streaming ssr api * add readable stream * code snippets * Rename strict effects / unsafe effects to use the reusable state terminology (#4505) * Add draft of 18 release post * Add links to speaker Twitter profiles * [18] Update upgrade guide * Fix typo in blog title * [18] Blog - add note for react native * [18] Add changelog info to blog posts * Edit Suspense for data fetching section * Update date * [18] Add links * Consistent title case * Update link to merged RFC * [18] Update APIs and links * [18] Add start/useTransition docs (#4479) * [18] Add start/useTransition docs * Updates based on feedback * [18] Generate heading IDs * Add note about Strict Mode * Just frameworks * Reorder, fix content * Typos * Clarify Suspense frameworks section * Revert lost changes that happened when I undo-ed in my editor Co-authored-by: salazarm &lt;salazarm@users.noreply.github.com&gt; Co-authored-by: Sebastian Silbermann &lt;silbermann.sebastian@gmail.com&gt; Co-authored-by: Sebastian Markbåge &lt;sebastian@calyptus.eu&gt; Co-authored-by: Andrew Clark &lt;git@andrewclark.io&gt; Co-authored-by: dan &lt;dan.abramov@gmail.com&gt;
3 years ago
const root = ReactDOM.createRoot(appRoot);
root.render(<Parent />);
```
[**Try it on CodePen**](https://codepen.io/gaearon/pen/jGBWpE)
Catching an event bubbling up from a portal in a parent component allows the development of more flexible abstractions that are not inherently reliant on portals. For example, if you render a `<Modal />` component, the parent can capture its events regardless of whether it's implemented using portals.