Error when trying to use Card

[matt1as]

When trying to using Cards from the example page I get the following error
Error: Invariant Violation: Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: undefined. Check the render method of Classified.

My code is

import React from 'react';
import ClassifiedStore  from '../stores/ClassifiedStore';
import connectToStores  from 'fluxible-addons-react/connectToStores';
import { Card, CardHeader, CardMedia, CardTitle, CardText, Avatar , CardActions, FlatButton} from 'material-ui/lib/card/card';

class Classified extends React.Component {
    render() {
      var classified = this.props.classified;
        return (
          <div>
          <Card>
            <CardHeader
              title="Title"
              subtitle="Subtitle"
              avatar={<Avatar>A</Avatar>}/>
            <CardHeader
              title="Demo Url Based Avatar"
              subtitle="Subtitle"
              avatar="http://lorempixel.com/100/100/nature/"/>
            <CardMedia overlay={<CardTitle title="Title" subtitle="Subtitle"/>}>
              <img src="http://lorempixel.com/600/337/nature/"/>
            </CardMedia>
            <CardTitle title="Title" subtitle="Subtitle"/>
            <CardActions>
              <FlatButton label="Action1"/>
              <FlatButton label="Action2"/>
            </CardActions>
            <CardText>
              Lorem ipsum dolor sit amet, consectetur adipiscing elit.
              Donec mattis pretium massa. Aliquam erat volutpat. Nulla facilisi.
              Donec vulputate interdum sollicitudin. Nunc lacinia auctor quam sed pellentesque.
              Aliquam dui mauris, mattis quis lacus id, pellentesque lobortis odio.
            </CardText>
          </Card>
          </div>
        );
    }
};

module.exports = connectToStores(
    Classified,
    [ClassifiedStore],
    function (context, props) {

        return {
            classified: context.getStore(ClassifiedStore).get(),
        }
    }
);

[c0b41]

need theme context
http://www.material-ui.com/#/customization/themes

1. Using React Lifecycle Methods with Context

or

1. Using ES7-style Decorator

[matt1as]

But why do I need theme context, I'm not using a custom theme, and it's not mentioned in any documentation I have seen.

[alitaheri]

@matt1as I don't think its related to theme. Could you try to find out exactly which one of these component is causing that error? I don't think it's related to Card

[oliviertassinari]

Your import is wrong, please use stackoverflow for this type of question.

import { Card, CardHeader, CardMedia, CardTitle, CardText, Avatar , CardActions, FlatButton} from 'material-ui/lib/card/card';