react-cqtoolbox/lib/lazy_image/LazyImage.js

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'use strict';

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

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 _class,
    _temp,
    _jsxFileName = '/Users/chenyutian0510/Documents/dev-js/chuangqi/react-cqtoolbox/components/lazy_image/LazyImage.js';

var _react = require('react');

var _react2 = _interopRequireDefault(_react);

var _reactDom = require('react-dom');

var _classnames2 = require('classnames');

var _classnames3 = _interopRequireDefault(_classnames2);

var _throttle = require('../utils/throttle');

var _throttle2 = _interopRequireDefault(_throttle);

var _cqKitDom = require('cq-kit-dom');

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

function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return 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; }

var components = [];
var throttleLazyImageHandler = void 0;

var loadImage = function loadImage(src) {
  var img = document.createElement('img');

  var promise = new Promise(function (resolve, reject) {
    img.addEventListener('load', resolve);
    img.addEventListener('error', reject);
  });

  img.src = src;

  return promise;
};

var pendImages = function pendImages(pending) {
  pending.forEach(function (component) {
    loadImage(component.props.url).then(function () {
      component.setState({ visible: true });
    });
  });
};

var lazyImageHandler = function lazyImageHandler() {

  var pending = [];

  components = components.filter(function (component) {
    var node = (0, _reactDom.findDOMNode)(component);
    if ((0, _cqKitDom.inViewport)(node)) {
      pending.push(component);
      return false;
    }

    return true;
  });

  if (!components.length) {
    window.removeEventListener('scroll', throttleLazyImageHandler);
    throttleLazyImageHandler = null;
  }

  pendImages(pending);
};

var LazyImage = (_temp = _class = function (_Component) {
  _inherits(LazyImage, _Component);

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

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

    _this.state = {
      visible: false
    };
    return _this;
  }

  _createClass(LazyImage, [{
    key: 'componentDidMount',
    value: function componentDidMount() {
      var scroll = this.props.scroll;


      if (scroll) {
        components.push(this);
      }

      if (!throttleLazyImageHandler && components.length) {
        throttleLazyImageHandler = (0, _throttle2.default)(lazyImageHandler);
        window.addEventListener('scroll', throttleLazyImageHandler);
      }
    }
  }, {
    key: 'componentWillUnmount',
    value: function componentWillUnmount() {
      var index = components.indexOf(this);
      if (index !== -1) {
        components.splice(index, 1);
      }

      if (components.length === 0) {
        window.removeEventListener('scroll', this.throttleLazyImageHandler);
      }
    }
  }, {
    key: 'render',
    value: function render() {
      var _props = this.props,
          url = _props.url,
          style = _props.style,
          theme = _props.theme,
          scroll = _props.scroll,
          height = _props.height,
          placeholder = _props.placeholder,
          className = _props.className,
          other = _objectWithoutProperties(_props, ['url', 'style', 'theme', 'scroll', 'height', 'placeholder', 'className']);

      var visible = this.state.visible;


      var classes = (0, _classnames3.default)(_defineProperty({}, theme.placeholder, !visible), className);

      var styles = Object.assign({ height: height }, style);

      var props = _extends({}, other, {
        style: styles,
        className: classes
      });

      if (!visible && _react2.default.isValidElement(placeholder)) {
        return _react2.default.cloneElement(placeholder, props);
      }

      return _react2.default.createElement('img', _extends({}, props, {
        src: visible ? url : placeholder,
        alt: '',
        __source: {
          fileName: _jsxFileName,
          lineNumber: 142
        },
        __self: this
      }));
    }
  }]);

  return LazyImage;
}(_react.Component), _class.propTypes = {
  url: _react.PropTypes.string.isRequired,
  scroll: _react.PropTypes.bool,
  height: _react.PropTypes.oneOfType([_react.PropTypes.number, _react.PropTypes.string]),
  placeholder: _react.PropTypes.node,
  className: _react.PropTypes.string,
  theme: _react.PropTypes.object
}, _class.defaultProps = {
  theme: {},
  scroll: true,
  height: 'auto',
  className: '',
  placeholder: require('./loader.gif')
}, _temp);
exports.default = LazyImage;