ep-react-ui/build/components/InView/LazyImage.js

EP react UI elements.

'use strict';

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

var _assign2 = require('lodash/assign');

var _assign3 = _interopRequireDefault(_assign2);

var _extends = Object.assign || function (target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i]; for (var key in source) { if (Object.prototype.hasOwnProperty.call(source, key)) { target[key] = source[key]; } } } return target; };

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 _react = require('react');

var _react2 = _interopRequireDefault(_react);

var _propTypes = require('prop-types');

var _propTypes2 = _interopRequireDefault(_propTypes);

var _classnames = require('classnames');

var _classnames2 = _interopRequireDefault(_classnames);

var _InView = require('./InView');

var _InView2 = _interopRequireDefault(_InView);

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

function _objectWithoutProperties(obj, keys) { var target = {}; for (var i in obj) { if (keys.indexOf(i) >= 0) continue; if (!Object.prototype.hasOwnProperty.call(obj, i)) continue; target[i] = obj[i]; } return target; }

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; } /**
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                * Image Lazy Load
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                */


var LazyImage = function (_PureComponent) {
    _inherits(LazyImage, _PureComponent);

    function LazyImage(props) {
        _classCallCheck(this, LazyImage);

        var _this = _possibleConstructorReturn(this, (LazyImage.__proto__ || Object.getPrototypeOf(LazyImage)).call(this, props));

        _this.state = {
            isLoaded: false
        };

        // events
        _this._onInView = _this._onInView.bind(_this);
        _this._onImageLoad = _this._onImageLoad.bind(_this);
        return _this;
    }

    _createClass(LazyImage, [{
        key: 'render',
        value: function render() {
            var _props = this.props,
                className = _props.className,
                uniqId = _props.uniqId,
                src = _props.src,
                width = _props.width,
                height = _props.height,
                useBg = _props.useBg,
                others = _objectWithoutProperties(_props, ['className', 'uniqId', 'src', 'width', 'height', 'useBg']);

            var isLoaded = this.state.isLoaded;


            var TagName = useBg ? 'div' : 'img';
            var attr = _extends({}, others, {
                className: (0, _classnames2.default)('img', className)
            });

            if (useBg) {
                attr.style = (0, _assign3.default)({}, this.props.style, {
                    width: width,
                    height: height,
                    backgroundImage: isLoaded ? 'url(' + src + ')' : undefined
                });
            } else {
                attr.src = isLoaded ? src : undefined;
                attr.width = width;
                attr.height = height;
            }

            return _react2.default.createElement(
                _InView2.default,
                {
                    className: 'LazyImage',
                    uniqId: uniqId,
                    onInView: this._onInView
                },
                _react2.default.createElement(TagName, attr)
            );
        }
    }, {
        key: '_onInView',
        value: function _onInView() {
            var src = this.props.src;
            var isLoaded = this.state.isLoaded;


            if (isLoaded) {
                return;
            }

            this.__img = new Image();
            this.__img.addEventListener('load', this._onImageLoad);
            this.__img.src = src;
        }
    }, {
        key: '_onImageLoad',
        value: function _onImageLoad() {
            this.__img.removeEventListener('load', this._onImageLoad);
            this.setState({ isLoaded: true });
        }
    }]);

    return LazyImage;
}(_react.PureComponent);

LazyImage.propTypes = {
    uniqId: _propTypes2.default.string.isRequired, // unique ID for InView to work
    src: _propTypes2.default.string.isRequired, // image src
    width: _propTypes2.default.string.isRequired, // image width
    height: _propTypes2.default.string.isRequired, // image height
    useBg: _propTypes2.default.bool // using background-image instead of img tag
};
exports.default = LazyImage;