weex-nuke/lib/Helper/rem.js

基于 Rax 、Weex 的高性能组件体系 ~~

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

var _typeof = typeof Symbol === "function" && typeof Symbol.iterator === "symbol" ? function (obj) { return typeof obj; } : function (obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; };

exports.caculateRemToPx = caculateRemToPx;
exports.removeRemUnit = removeRemUnit;

var _nukeEnv = require('../Env/index.js');

/**
 * @description parse rem to even px to solve andoird float px issue.
 */
function caculateRemToPx(rem) {
  var defaultWidth = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 750;

  // Default 1 rem to 1 px
  if ((typeof rem === 'undefined' ? 'undefined' : _typeof(rem)) === 'object' && 'raw' in rem) {
    rem = rem.raw;
  }
  if (_nukeEnv.isWeex) return rem;
  rem = exports.removeRemUnit(rem);
  var defaultPixUnit = document.documentElement.clientWidth / defaultWidth;
  var num = Math.round(parseFloat(rem) * defaultPixUnit);
  if (num % 2 === 0) {
    return num + 'px';
  }
  return num - 1 + 'px';
}
/**
 * @description remove rem unit for string like 12rem => 12
 * @param {string or number} rem
 */
function removeRemUnit(rem) {
  rem = String(rem);
  return rem.replace('rem', '');
}