ButtonUnstyled accepts a wide range of custom elements beyond HTML elements.
You can even use SVGs, as the following demo illustrates:
Focus on disabled buttons
Similarly to the native HTML <button> element, the ButtonUnstyled component can't receive focus when it's disabled.
This may reduce its accessibility, as screen readers won't be able to announce the existence and state of the button.
The focusableWhenDisabled prop lets you change this behavior.
When this prop is set, the underlying button does not set the disabled prop.
Instead, aria-disabled is used, which makes the button focusable.
This should be used whenever the disabled button needs to be read by screen readers.
MUI Base uses this prop internally in menu items, making it possible to use the keyboard to navigate to disabled items (in compliance with ARIA guidelines).
The focusWhenDisabled prop works the same when the root slot is customized, except that the aria-disabled attribute is used no regardless of the prop's state.
The ability to receive focus is controlled internally by the tabindex attribute.
The useButton hook lets you use the functionality of ButtonUnstyled in other components.
It returns props to be placed on a custom button element, along with fields representing the internal state of the button.
The useButton hook requires the ref of the element it's used on.
Additionally, you need to provide the component prop (unless you intend to use the native HTML <button>).
If a ButtonUnstyled is customized with a non-button element (i.e. <ButtonUnstyled component="span" />), it will not submit the form it's in when clicked.
Similarly, <ButtonUnstyled component="span" type="reset"> will not reset its parent form.