webcomponent/build/index.js

lightweight helpers for constructing web components

'use strict';

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

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _extendableHtmlElement = require('./extendable-html-element');

var _extendableHtmlElement2 = _interopRequireDefault(_extendableHtmlElement);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function _possibleConstructorReturn(self, call) { if (!self) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return call && (typeof call === "object" || typeof call === "function") ? call : self; }

function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function, not " + typeof superClass); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }

// WebComponent = thin wrapper around HTMLElement with convenience methods
var WebComponent = function (_ExtendableHTMLElemen) {
  _inherits(WebComponent, _ExtendableHTMLElemen);

  function WebComponent() {
    _classCallCheck(this, WebComponent);

    return _possibleConstructorReturn(this, (WebComponent.__proto__ || Object.getPrototypeOf(WebComponent)).apply(this, arguments));
  }

  _createClass(WebComponent, [{
    key: 'getJSONAttribute',


    // parse an attribute which has been serialized as JSON
    // pass an optional errorHandler in case JSON.parse() fails
    value: function getJSONAttribute(attrName) {
      var errorHandler = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : function () {
        return null;
      };

      try {
        return JSON.parse(this.getAttribute(attrName));
      } catch (e) {
        return errorHandler(attrName, e);
      }
    }

    // Parse number attributes. Examples:
    // null      -> null
    // ""        -> null
    // "asd"     -> null
    // "123asd"  -> null
    // "0"       -> 0
    // "123"     -> 123
    // "-123"    -> -123
    // "123.45"  -> 123.45

  }, {
    key: 'getNumberAttribute',
    value: function getNumberAttribute(attrName) {
      var attrVal = this.getAttribute(attrName);
      if (!attrVal) {
        return null;
      } else {
        var num = Number(attrVal);
        return Number.isNaN(num) ? null : num;
      }
    }

    // check whether a boolean attribute is 'enabled' in an element instance
    // taking into account usages such as:
    // <my-element myattr="true">    -> enabled
    // <my-element myattr>           -> enabled
    // <my-element myattr="myattr">  -> enabled
    // <my-element myattr="false">   -> disabled
    // <my-element>                  -> disabled

  }, {
    key: 'isAttributeEnabled',
    value: function isAttributeEnabled(attrName) {
      var attrVal = this.getAttribute(attrName);
      return typeof attrVal === 'string' && ['', 'true', attrName.toLowerCase()].indexOf(attrVal.toLowerCase()) !== -1;
    }
  }]);

  return WebComponent;
}(_extendableHtmlElement2.default);

exports.default = WebComponent;