Nextjs
Reference
Button Group
The ButtonGroup component allows for the grouping of related buttons into a single unit.
Basic button group
Buttons can be grouped by enclosing them within the 
ButtonGroup component, where they must be direct children.import * as React from 'react';
import Button from '@mui/material/Button';
import ButtonGroup from '@mui/material/ButtonGroup';
export default function BasicButtonGroup() {
  return (
    <ButtonGroup variant="contained" aria-label="Basic button group">
      <Button>One</Button>
      <Button>Two</Button>
      <Button>Three</Button>
    </ButtonGroup>
  );
}Button variants
All standard button styles are supported.
import * as React from 'react';
import Button from '@mui/material/Button';
import ButtonGroup from '@mui/material/ButtonGroup';
import Box from '@mui/material/Box';
export default function VariantButtonGroup() {
  return (
    <Box
      sx={{
        display: 'flex',
        flexDirection: 'column',
        alignItems: 'center',
        '& > *': {
          m: 1,
        },
      }}
    >
      <ButtonGroup variant="outlined" aria-label="Basic button group">
        <Button>One</Button>
        <Button>Two</Button>
        <Button>Three</Button>
      </ButtonGroup>
      <ButtonGroup variant="text" aria-label="Basic button group">
        <Button>One</Button>
        <Button>Two</Button>
        <Button>Three</Button>
      </ButtonGroup>
    </Box>
  );
}Sizes and colors
The 
size and color props allow customization of the button group's appearance.import * as React from 'react';
import Button from '@mui/material/Button';
import Box from '@mui/material/Box';
import ButtonGroup from '@mui/material/ButtonGroup';
const buttons = [
  <Button key="one">One</Button>,
  <Button key="two">Two</Button>,
  <Button key="three">Three</Button>,
];
export default function GroupSizesColors() {
  return (
    <Box
      sx={{
        display: 'flex',
        flexDirection: 'column',
        alignItems: 'center',
        '& > *': {
          m: 1,
        },
      }}
    >
      <ButtonGroup size="small" aria-label="Small button group">
        {buttons}
      </ButtonGroup>
      <ButtonGroup color="secondary" aria-label="Medium-sized button group">
        {buttons}
      </ButtonGroup>
      <ButtonGroup size="large" aria-label="Large button group">
        {buttons}
      </ButtonGroup>
    </Box>
  );
}Vertical group
The button group can be arranged vertically by utilizing the 
orientation prop.import * as React from 'react';
import Button from '@mui/material/Button';
import ButtonGroup from '@mui/material/ButtonGroup';
import Box from '@mui/material/Box';
const buttons = [
  <Button key="one">One</Button>,
  <Button key="two">Two</Button>,
  <Button key="three">Three</Button>,
];
export default function GroupOrientation() {
  return (
    <Box
      sx={{
        display: 'flex',
        '& > *': {
          m: 1,
        },
      }}
    >
      <ButtonGroup orientation="vertical" aria-label="Vertical button group">
        {buttons}
      </ButtonGroup>
      <ButtonGroup
        orientation="vertical"
        aria-label="Vertical button group"
        variant="contained"
      >
        {buttons}
      </ButtonGroup>
      <ButtonGroup
        orientation="vertical"
        aria-label="Vertical button group"
        variant="text"
      >
        {buttons}
      </ButtonGroup>
    </Box>
  );
}Split button
The 
ButtonGroup component can be used to create a split button, where the dropdown can modify the button's action (as shown in this example) or trigger a related action immediately.import * as React from 'react';
import Button from '@mui/material/Button';
import ButtonGroup from '@mui/material/ButtonGroup';
import ArrowDropDownIcon from '@mui/icons-material/ArrowDropDown';
import ClickAwayListener from '@mui/material/ClickAwayListener';
import Grow from '@mui/material/Grow';
import Paper from '@mui/material/Paper';
import Popper from '@mui/material/Popper';
import MenuItem from '@mui/material/MenuItem';
import MenuList from '@mui/material/MenuList';
const options = ['Create a merge commit', 'Squash and merge', 'Rebase and merge'];
export default function SplitButton() {
  const [open, setOpen] = React.useState(false);
  const anchorRef = React.useRef<HTMLDivElement>(null);
  const [selectedIndex, setSelectedIndex] = React.useState(1);
  const handleClick = () => {
    console.info(`You clicked ${options[selectedIndex]}`);
  };
  const handleMenuItemClick = (
    event: React.MouseEvent<HTMLLIElement, MouseEvent>,
    index: number,
  ) => {
    setSelectedIndex(index);
    setOpen(false);
  };
  const handleToggle = () => {
    setOpen((prevOpen) => !prevOpen);
  };
  const handleClose = (event: Event) => {
    if (
      anchorRef.current &&
      anchorRef.current.contains(event.target as HTMLElement)
    ) {
      return;
    }
    setOpen(false);
  };
  return (
    <React.Fragment>
      <ButtonGroup
        variant="contained"
        ref={anchorRef}
        aria-label="Button group with a nested menu"
      >
        <Button onClick={handleClick}>{options[selectedIndex]}</Button>
        <Button
          size="small"
          aria-controls={open ? 'split-button-menu' : undefined}
          aria-expanded={open ? 'true' : undefined}
          aria-label="select merge strategy"
          aria-haspopup="menu"
          onClick={handleToggle}
        >
          <ArrowDropDownIcon />
        </Button>
      </ButtonGroup>
      <Popper
        sx={{ zIndex: 1 }}
        open={open}
        anchorEl={anchorRef.current}
        role={undefined}
        transition
        disablePortal
      >
        {({ TransitionProps, placement }) => (
          <Grow
            {...TransitionProps}
            style={{
              transformOrigin:
                placement === 'bottom' ? 'center top' : 'center bottom',
            }}
          >
            <Paper>
              <ClickAwayListener onClickAway={handleClose}>
                <MenuList id="split-button-menu" autoFocusItem>
                  {options.map((option, index) => (
                    <MenuItem
                      key={option}
                      disabled={index === 2}
                      selected={index === selectedIndex}
                      onClick={(event) => handleMenuItemClick(event, index)}
                    >
                      {option}
                    </MenuItem>
                  ))}
                </MenuList>
              </ClickAwayListener>
            </Paper>
          </Grow>
        )}
      </Popper>
    </React.Fragment>
  );
}Disabled elevation
The 
disableElevation prop can be used to remove the elevation effect from the button group.import * as React from 'react';
import ButtonGroup from '@mui/material/ButtonGroup';
import Button from '@mui/material/Button';
export default function DisableElevation() {
  return (
    <ButtonGroup
      disableElevation
      variant="contained"
      aria-label="Disabled button group"
    >
      <Button>One</Button>
      <Button>Two</Button>
    </ButtonGroup>
  );
}Loading
The 
loading prop on the Button component can be used to place buttons in a loading state, preventing user interactions.import * as React from 'react';
import ButtonGroup from '@mui/material/ButtonGroup';
import Button from '@mui/material/Button';
import SaveIcon from '@mui/icons-material/Save';
export default function LoadingButtonGroup() {
  return (
    <ButtonGroup variant="outlined" aria-label="Loading button group">
      <Button>Submit</Button>
      <Button>Fetch data</Button>
      <Button loading loadingPosition="start" startIcon={<SaveIcon />}>
        Save
      </Button>
    </ButtonGroup>
  );
}