Magento 2: Set calculation based on Custom value

Question

I want to do calculation based on that value in order summary extra field

 getValue: function() {
                var price = 0;
                if (this.totals()) {
                    price = totals.getSegment('fee').value ;
                var tex = totals.getSegment('fee').value ;
                price = (this.totals().subtotal) / tex;
                }
                // price = 101;
                return this.getFormattedPrice(price);

that was by fee.js file code I already do code but they not reflected can any one help me.

Answer 1

You can do that code in that defined file see Extention/Module/view/frontend/web/js/view/checkout/cart/totals

define([
        'ko',
        'uiComponent',
        'Magento_Checkout/js/model/quote',
        'Magento_Catalog/js/price-utils',
        'Magento_Checkout/js/model/totals'

    ], function (ko, Component, quote, priceUtils, totals) {
        'use strict';
        var show_hide_Extrafee_blockConfig = window.checkoutConfig.show_hide_Extrafee_block;
        var fee_label = window.checkoutConfig.fee_label;
        var custom_tax_percentage = window.checkoutConfig.custom_fee_amount;
        var subtotal_amount =  parseFloat(totals.totals()['subtotal']);
        var custom_fee_amount = subtotal_amount/custom_tax_percentage;
        return Component.extend({

            totals: quote.getTotals(),
            canVisibleExtrafeeBlock: show_hide_Extrafee_blockConfig,
            getFormattedPrice: ko.observable(priceUtils.formatPrice(custom_fee_amount, quote.getPriceFormat())),
            getFeeLabel:ko.observable(fee_label),
            isDisplayed: function () {
                return this.getValue() != 0;
            },
            getValue: function() {
                var price = 0;
                if (this.totals() && totals.getSegment('fee')) {
                    price = totals.getSegment('fee').value;
                }
                // price = 1;
                return price;
            }
        });
    });