Vulcan/packages/vulcan-forms/lib/FormGroup.jsx

import React, { PureComponent } from 'react';
import PropTypes from 'prop-types';
import FormComponent from './FormComponent.jsx';
import { Components } from 'meteor/vulcan:core';
import classNames from 'classnames';

class FormGroup extends PureComponent {

  constructor(props) {
    super(props);
    this.toggle = this.toggle.bind(this);
    this.renderHeading = this.renderHeading.bind(this);
    this.state = {
      collapsed: props.startCollapsed || false
    }
  }

  toggle() {
    this.setState({
      collapsed: !this.state.collapsed
    })
  }

  renderHeading() {
    return (
      <div className="form-section-heading" onClick={this.toggle}>
        <h3 className="form-section-heading-title">{this.props.label}</h3>
        <span className="form-section-heading-toggle">
          {this.state.collapsed ? <Components.Icon name="expand" /> : <Components.Icon name="collapse" />}
        </span>
      </div>
    )
  }

  render() {

    const hasErrors = _.some(this.props.fields, field => field.errors && field.errors.length);

    return (
      <div className="form-section">
        {this.props.name === 'default' ? null : this.renderHeading()}
        <div className={classNames({'form-section-collapsed': this.state.collapsed && !hasErrors})}>
          {this.props.fields.map(field => <FormComponent key={field.name} {...field} updateCurrentValues={this.props.updateCurrentValues} />)}
        </div>
      </div>
    )
  }
}

FormGroup.propTypes = {
  name: PropTypes.string,
  label: PropTypes.string,
  order: PropTypes.number,
  fields: PropTypes.array,
  updateCurrentValues: PropTypes.func
}

export default FormGroup;