How to set selected and hover color of ListItem in Material UI?

问题

Can't get 'selected' or 'hover colors to work for ListItem. For selected tried setting its classes like:

<ListItem selected button key="home" classes={{ selected: classes.listItemSelected }} >
            <ListItemText primary="Hi"/>
/ListItem>

and then setting the style like:

const useStyles = makeStyles((theme) => ({

  listItemSelected:{
    backgroundColor: "#ff0000",
  },

}));

But it doesnt do anything, the 'selected' is described in the ListItem component API here: https://material-ui.com/api/list-item/

How do you get to set the color of both the selected and hover for ListItem?

回答1:

Below is the portion of the default ListItem styles that deals with the background color:

export const styles = (theme) => ({
  /* Styles applied to the (normally root) `component` element. May be wrapped by a `container`. */
  root: {
    '&$focusVisible': {
      backgroundColor: theme.palette.action.selected,
    },
    '&$selected, &$selected:hover': {
      backgroundColor: theme.palette.action.selected,
    },
    '&$disabled': {
      opacity: 0.5,
    },
  },
  /* Pseudo-class applied to the `component`'s `focusVisibleClassName` prop if `button={true}`. */
  focusVisible: {},
  /* Styles applied to the inner `component` element if `button={true}`. */
  button: {
    transition: theme.transitions.create('background-color', {
      duration: theme.transitions.duration.shortest,
    }),
    '&:hover': {
      textDecoration: 'none',
      backgroundColor: theme.palette.action.hover,
      // Reset on touch devices, it doesn't add specificity
      '@media (hover: none)': {
        backgroundColor: 'transparent',
      },
    },
  },
  /* Pseudo-class applied to the root element if `selected={true}`. */
  selected: {},
});

The important thing to notice is that the selected styling is done via a combination of two classes (root and selected), so if you try to override it using a single class you will not have sufficient specificity.

Below is an example showing one way to override the selected and hover states:

import React from "react";
import { makeStyles, withStyles } from "@material-ui/core/styles";
import List from "@material-ui/core/List";
import MuiListItem from "@material-ui/core/ListItem";
import ListItemIcon from "@material-ui/core/ListItemIcon";
import ListItemText from "@material-ui/core/ListItemText";
import Divider from "@material-ui/core/Divider";
import InboxIcon from "@material-ui/icons/Inbox";
import DraftsIcon from "@material-ui/icons/Drafts";

const useStyles = makeStyles(theme => ({
  root: {
    width: "100%",
    maxWidth: 360,
    backgroundColor: theme.palette.background.paper
  }
}));

const ListItem = withStyles({
  root: {
    "&$selected": {
      backgroundColor: "red",
      color: "white"
    },
    "&$selected:hover": {
      backgroundColor: "purple",
      color: "white"
    },
    "&:hover": {
      backgroundColor: "blue",
      color: "white"
    }
  },
  selected: {}
})(MuiListItem);

export default function SelectedListItem() {
  const classes = useStyles();
  const [selectedIndex, setSelectedIndex] = React.useState(1);

  const handleListItemClick = (event, index) => {
    setSelectedIndex(index);
  };

  return (
    <div className={classes.root}>
      <List component="nav" aria-label="main mailbox folders">
        <ListItem
          button
          selected={selectedIndex === 0}
          onClick={event => handleListItemClick(event, 0)}
        >
          <ListItemIcon>
            <InboxIcon />
          </ListItemIcon>
          <ListItemText primary="Inbox" />
        </ListItem>
        <ListItem
          button
          selected={selectedIndex === 1}
          onClick={event => handleListItemClick(event, 1)}
        >
          <ListItemIcon>
            <DraftsIcon />
          </ListItemIcon>
          <ListItemText primary="Drafts" />
        </ListItem>
      </List>
      <Divider />
      <List component="nav" aria-label="secondary mailbox folder">
        <ListItem
          button
          selected={selectedIndex === 2}
          onClick={event => handleListItemClick(event, 2)}
        >
          <ListItemText primary="Trash" />
        </ListItem>
        <ListItem
          button
          selected={selectedIndex === 3}
          onClick={event => handleListItemClick(event, 3)}
        >
          <ListItemText primary="Spam" />
        </ListItem>
      </List>
    </div>
  );
}