Composition
Material UI tries to make composition as easy as possible.
Wrapping components
To provide maximum flexibility and performance, Material UI needs a way to know the nature of the child elements a component receives.
To solve this problem, we tag some of the components with a muiName
static property when needed.
You may, however, need to wrap a component in order to enhance it, which can conflict with the muiName
solution.
If you wrap a component, verify if that component has this static property set.
If you encounter this issue, you need to use the same tag for your wrapping component that is used with the wrapped component. In addition, you should forward the props, as the parent component may need to control the wrapped components props.
Let's see an example:
const WrappedIcon = (props) => <Icon {...props} />;
WrappedIcon.muiName = Icon.muiName;
Component prop
Material UI allows you to change the root element that will be rendered via a prop called component
.
For example, by default a List
component will render a <ul>
element.
This can be changed by passing a React component to the component
prop.
The following example renders the List
component with a <menu>
element as root element instead:
<List component="menu">
<ListItem>
<ListItemButton>
<ListItemText primary="Trash" />
</ListItemButton>
</ListItem>
<ListItem>
<ListItemButton>
<ListItemText primary="Spam" />
</ListItemButton>
</ListItem>
</List>
This pattern is very powerful and allows for great flexibility, as well as a way to interoperate with other libraries, such as your favorite routing or forms library.
Passing other React components
You can pass any other React component to component
prop. For example, you can pass Link
component from react-router
:
import { Link } from 'react-router';
import Button from '@mui/material/Button';
function Demo() {
return (
<Button component={Link} to="/react-router">
React router link
</Button>
);
}
With TypeScript
To be able to use the component
prop, the type of the props should be used with type arguments. Otherwise, the component
prop will not be present.
The examples below use TypographyProps
but the same will work for any component which has props defined with OverrideProps
.
import { TypographyProps } from '@mui/material/Typography';
function CustomComponent(props: TypographyProps<'a', { component: 'a' }>) {
/* ... */
}
// ...
<CustomComponent component="a" />;
Now the CustomComponent
can be used with a component
prop which should be set to 'a'
.
In addition, the CustomComponent
will have all props of a <a>
HTML element.
The other props of the Typography
component will also be present in props of the CustomComponent
.
You can find a code example with the Button and react-router in these demos.
Generic
It's also possible to have a generic custom component which accepts any React component, including built-in components.
function GenericCustomComponent<C extends React.ElementType>(
props: TypographyProps<C, { component?: C }>,
) {
/* ... */
}
If the GenericCustomComponent
is used with a component
prop provided, it should also have all props required by the provided component.
function ThirdPartyComponent({ prop1 }: { prop1: string }) {
/* ... */
}
// ...
<GenericCustomComponent component={ThirdPartyComponent} prop1="some value" />;
The prop1
became required for the GenericCustomComponent
as the ThirdPartyComponent
has it as a requirement.
Not every component fully supports any component type you pass in.
If you encounter a component that rejects its component
props in TypeScript, please open an issue.
There is an ongoing effort to fix this by making component props generic.
Caveat with refs
This section covers caveats when using a custom component as children
or for the
component
prop.
Some of the components need access to the DOM node. This was previously possible
by using ReactDOM.findDOMNode
. This function is deprecated in favor of ref
and
ref forwarding. However, only the following component types can be given a ref
:
- Any Material UI component
- class components, that is
React.Component
orReact.PureComponent
- DOM (or host) components, for example
div
orbutton
- React.forwardRef components
- React.lazy components
- React.memo components
If you don't use one of the above types when using your components in conjunction with Material UI, you might see a warning from React in your console similar to:
Note that you will still get this warning for lazy
and memo
components if their wrapped component can't hold a ref.
In some instances, an additional warning is issued to help with debugging, similar to:
Only the two most common use cases are covered. For more information see this section in the official React docs.
-const MyButton = () => <div role="button" />;
+const MyButton = React.forwardRef((props, ref) =>
+ <div role="button" {...props} ref={ref} />);
<Button component={MyButton} />;
-const SomeContent = props => <div {...props}>Hello, World!</div>;
+const SomeContent = React.forwardRef((props, ref) =>
+ <div {...props} ref={ref}>Hello, World!</div>);
<Tooltip title="Hello again."><SomeContent /></Tooltip>;
To find out if the Material UI component you're using has this requirement, check out the props API documentation for that component. If you need to forward refs the description will link to this section.
Caveat with StrictMode
If you use class components for the cases described above you will still see
warnings in React.StrictMode
.
ReactDOM.findDOMNode
is used internally for backwards compatibility.
You can use React.forwardRef
and a designated prop in your class component to forward the ref
to a DOM component.
Doing so should not trigger any more warnings related to the deprecation of ReactDOM.findDOMNode
.
class Component extends React.Component {
render() {
- const { props } = this;
+ const { forwardedRef, ...props } = this.props;
return <div {...props} ref={forwardedRef} />;
}
}
-export default Component;
+export default React.forwardRef((props, ref) => <Component {...props} forwardedRef={ref} />);