metamask-extension/ui/app/pages/send/send-content/send-gas-row/gas-fee-display/gas-fee-display.component.js

import React, { Component } from 'react'
import PropTypes from 'prop-types'
import UserPreferencedCurrencyDisplay from '../../../../../components/app/user-preferenced-currency-display'
import { PRIMARY, SECONDARY } from '../../../../../helpers/constants/common'

export default class GasFeeDisplay extends Component {

  static propTypes = {
    gasLoadingError: PropTypes.bool,
    gasTotal: PropTypes.string,
    onReset: PropTypes.func,
  }

  static contextTypes = {
    t: PropTypes.func,
  }

  render () {
    const { gasTotal, gasLoadingError, onReset } = this.props

    return (
      <div className="send-v2__gas-fee-display">
        {gasTotal
          ? (
            <div className="currency-display">
              <UserPreferencedCurrencyDisplay
                value={gasTotal}
                type={PRIMARY}
              />
              <UserPreferencedCurrencyDisplay
                className="currency-display__converted-value"
                value={gasTotal}
                type={SECONDARY}
              />
            </div>
          )
          : gasLoadingError
            ? (
              <div className="currency-display.currency-display--message">
                {this.context.t('setGasPrice')}
              </div>
            )
            : (
              <div className="currency-display">
                {this.context.t('loading')}
              </div>
            )
        }
        <button
          className="gas-fee-reset"
          onClick={onReset}
        >
          { this.context.t('reset') }
        </button>
      </div>
    )
  }
}