how to use a theme from material ui code example

Example 1: material ui change theme

import { createMuiTheme } from '@material-ui/core/styles';

const theme = createMuiTheme({
  palette: {
    primary: {
      // light: will be calculated from palette.primary.main,
      main: '#ff4400',
      // dark: will be calculated from palette.primary.main,
      // contrastText: will be calculated to contrast with palette.primary.main
    },
    secondary: {
      light: '#0066ff',
      main: '#0044ff',
      // dark: will be calculated from palette.secondary.main,
      contrastText: '#ffcc00',
    },
    // error: will use the default color
  },
});

Example 2: use theme in class component material ui

import { withStyles } from "@material-ui/core/styles";

const styles = theme => ({
  root: {
    backgroundColor: "red"
  }
});

class ClassComponent extends Component {
  state = {
    searchNodes: ""
  };

  render() {
    const { classes } = this.props;
    return (
      
Hello!
    );
  }
}

export default withStyles(styles, { withTheme: true })(ClassComponent);