Currency.php

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */

namespace Magento\Backend\Block\Widget\Grid\Column\Renderer;

/**
 * Backend grid item renderer currency
 *
 * @api
 * @since 100.0.2
 */
class Currency extends \Magento\Backend\Block\Widget\Grid\Column\Renderer\AbstractRenderer
{
    /**
     * @var int
     */
    protected $_defaultWidth = 100;

    /**
     * Currency objects cache
     *
     * @var \Magento\Framework\DataObject[]
     */
    protected static $_currencies = [];

    /**
     * Application object
     *
     * @var \Magento\Store\Model\StoreManagerInterface
     */
    protected $_storeManager;

    /**
     * @var \Magento\Directory\Model\Currency\DefaultLocator
     */
    protected $_currencyLocator;

    /**
     * @var \Magento\Directory\Model\Currency
     */
    protected $_defaultBaseCurrency;

    /**
     * @var \Magento\Framework\Locale\CurrencyInterface
     */
    protected $_localeCurrency;

    /**
     * @param \Magento\Backend\Block\Context $context
     * @param \Magento\Store\Model\StoreManagerInterface $storeManager
     * @param \Magento\Directory\Model\Currency\DefaultLocator $currencyLocator
     * @param \Magento\Directory\Model\CurrencyFactory $currencyFactory
     * @param \Magento\Framework\Locale\CurrencyInterface $localeCurrency
     * @param array $data
     */
    public function __construct(
        \Magento\Backend\Block\Context $context,
        \Magento\Store\Model\StoreManagerInterface $storeManager,
        \Magento\Directory\Model\Currency\DefaultLocator $currencyLocator,
        \Magento\Directory\Model\CurrencyFactory $currencyFactory,
        \Magento\Framework\Locale\CurrencyInterface $localeCurrency,
        array $data = []
    ) {
        parent::__construct($context, $data);
        $this->_storeManager = $storeManager;
        $this->_currencyLocator = $currencyLocator;
        $this->_localeCurrency = $localeCurrency;
        $defaultBaseCurrencyCode = $currencyLocator->getDefaultCurrency($this->_request);
        $this->_defaultBaseCurrency = $currencyFactory->create()->load($defaultBaseCurrencyCode);
    }

    /**
     * Renders grid column
     *
     * @param   \Magento\Framework\DataObject $row
     * @return  string
     */
    public function render(\Magento\Framework\DataObject $row)
    {
        if ($data = (string)$this->_getValue($row)) {
            $currency_code = $this->_getCurrencyCode($row);
            $data = (float)$data * $this->_getRate($row);
            $sign = (bool)(int)$this->getColumn()->getShowNumberSign() && $data > 0 ? '+' : '';
            $data = sprintf("%f", $data);
            $data = $this->_localeCurrency->getCurrency($currency_code)->toCurrency($data);
            return $sign . $data;
        }
        return $this->getColumn()->getDefault();
    }

    /**
     * Returns currency code, false on error
     *
     * @param \Magento\Framework\DataObject $row
     * @return string
     */
    protected function _getCurrencyCode($row)
    {
        if ($code = $this->getColumn()->getCurrencyCode()) {
            return $code;
        }
        if ($code = $row->getData($this->getColumn()->getCurrency())) {
            return $code;
        }

        return $this->_currencyLocator->getDefaultCurrency($this->_request);
    }

    /**
     * Get rate for current row, 1 by default
     *
     * @param \Magento\Framework\DataObject $row
     * @return float|int
     */
    protected function _getRate($row)
    {
        if ($rate = $this->getColumn()->getRate()) {
            return (float)$rate;
        }
        if ($rate = $row->getData($this->getColumn()->getRateField())) {
            return (float)$rate;
        }
        return $this->_defaultBaseCurrency->getRate($this->_getCurrencyCode($row));
    }

    /**
     * Returns HTML for CSS
     *
     * @return string
     */
    public function renderCss()
    {
        return parent::renderCss() . ' a-right';
    }
}