TypeScript
You can add static typing to JavaScript to improve developer productivity and code quality thanks to TypeScript.
Minimum configuration
Material UI requires a minimum version of TypeScript 3.5. Have a look at the Create React App with TypeScript example.
For types to work, it's recommended that you have at least the following options enabled in your tsconfig.json
:
{
"compilerOptions": {
"lib": ["es6", "dom"],
"noImplicitAny": true,
"noImplicitThis": true,
"strictNullChecks": true
}
}
The strict mode options are the same that are required for every types package
published in the @types/
namespace.
Using a less strict tsconfig.json
or omitting some of the libraries might cause errors.
To get the best type experience with the types we recommend setting "strict": true
.
Handling value
and event handlers
Many components concerned with user input offer a value
prop or event handlers
which include the current value
. In most situations that value
is only handled
within React which allows it be of any type, such as objects or arrays.
However, that type cannot be verified at compile time in situations where it depends
on the component's children e.g. for Select
or RadioGroup
. This means that
the soundest option is to type it as unknown
and let the developer decide
how they want to narrow that type down. We do not offer the possibility to use a generic
type in those cases for the same reasons event.target
is not generic in React.
The demos include typed variants that use type casting. It is an acceptable tradeoff because the types are all located in a single file and are very basic. You have to decide for yourself if the same tradeoff is acceptable for you. The library types are strict by default and loose via opt-in.
Customization of Theme
Moved to /customization/theming/#custom-variables.
Complications with the component
prop
Because of some TypeScript limitations, using the component
prop can be problematic if you are creating your custom component based on the Material UI's components.
For the composition of the components, you will likely need to use one of these two options:
- Wrap the Material UI component in order to enhance it
- Use the
styled()
utility in order to customize the styles of the component
If you are using the first option, take a look at the composition guide for more details.
If you are using the styled()
utility (regardless of whether it comes from @mui/material
or @emotion/styled
), you will need to cast the resulting component as shown below:
import Button from '@mui/material/Button';
import { styled } from '@mui/material/styles';
const CustomButton = styled(Button)({
// your custom styles go here
}) as typeof Button;