primereact/components/deferredcontent/DeferredContent.js

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"use strict";

function _typeof(obj) { "@babel/helpers - typeof"; if (typeof Symbol === "function" && typeof Symbol.iterator === "symbol") { _typeof = function _typeof(obj) { return typeof obj; }; } else { _typeof = function _typeof(obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }; } return _typeof(obj); }

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.DeferredContent = void 0;

var _react = _interopRequireWildcard(require("react"));

var _propTypes = _interopRequireDefault(require("prop-types"));

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

function _getRequireWildcardCache() { if (typeof WeakMap !== "function") return null; var cache = new WeakMap(); _getRequireWildcardCache = function _getRequireWildcardCache() { return cache; }; return cache; }

function _interopRequireWildcard(obj) { if (obj && obj.__esModule) { return obj; } if (obj === null || _typeof(obj) !== "object" && typeof obj !== "function") { return { default: obj }; } var cache = _getRequireWildcardCache(); if (cache && cache.has(obj)) { return cache.get(obj); } var newObj = {}; var hasPropertyDescriptor = Object.defineProperty && Object.getOwnPropertyDescriptor; for (var key in obj) { if (Object.prototype.hasOwnProperty.call(obj, key)) { var desc = hasPropertyDescriptor ? Object.getOwnPropertyDescriptor(obj, key) : null; if (desc && (desc.get || desc.set)) { Object.defineProperty(newObj, key, desc); } else { newObj[key] = obj[key]; } } } newObj.default = obj; if (cache) { cache.set(obj, newObj); } return newObj; }

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

function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }

function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, writable: true, configurable: true } }); if (superClass) _setPrototypeOf(subClass, superClass); }

function _setPrototypeOf(o, p) { _setPrototypeOf = Object.setPrototypeOf || function _setPrototypeOf(o, p) { o.__proto__ = p; return o; }; return _setPrototypeOf(o, p); }

function _createSuper(Derived) { var hasNativeReflectConstruct = _isNativeReflectConstruct(); return function _createSuperInternal() { var Super = _getPrototypeOf(Derived), result; if (hasNativeReflectConstruct) { var NewTarget = _getPrototypeOf(this).constructor; result = Reflect.construct(Super, arguments, NewTarget); } else { result = Super.apply(this, arguments); } return _possibleConstructorReturn(this, result); }; }

function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }

function _assertThisInitialized(self) { if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }

function _isNativeReflectConstruct() { if (typeof Reflect === "undefined" || !Reflect.construct) return false; if (Reflect.construct.sham) return false; if (typeof Proxy === "function") return true; try { Boolean.prototype.valueOf.call(Reflect.construct(Boolean, [], function () {})); return true; } catch (e) { return false; } }

function _getPrototypeOf(o) { _getPrototypeOf = Object.setPrototypeOf ? Object.getPrototypeOf : function _getPrototypeOf(o) { return o.__proto__ || Object.getPrototypeOf(o); }; return _getPrototypeOf(o); }

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; }

var DeferredContent = /*#__PURE__*/function (_Component) {
  _inherits(DeferredContent, _Component);

  var _super = _createSuper(DeferredContent);

  function DeferredContent() {
    var _this;

    _classCallCheck(this, DeferredContent);

    _this = _super.call(this);
    _this.state = {
      loaded: false
    };
    return _this;
  }

  _createClass(DeferredContent, [{
    key: "componentDidMount",
    value: function componentDidMount() {
      if (!this.state.loaded) {
        if (this.shouldLoad()) this.load();else this.bindScrollListener();
      }
    }
  }, {
    key: "bindScrollListener",
    value: function bindScrollListener() {
      var _this2 = this;

      this.documentScrollListener = function () {
        if (_this2.shouldLoad()) {
          _this2.load();

          _this2.unbindScrollListener();
        }
      };

      window.addEventListener('scroll', this.documentScrollListener);
    }
  }, {
    key: "unbindScrollListener",
    value: function unbindScrollListener() {
      if (this.documentScrollListener) {
        window.removeEventListener('scroll', this.documentScrollListener);
        this.documentScrollListener = null;
      }
    }
  }, {
    key: "shouldLoad",
    value: function shouldLoad() {
      if (this.state.loaded) {
        return false;
      } else {
        var rect = this.container.getBoundingClientRect();
        var docElement = document.documentElement;
        var winHeight = docElement.clientHeight;
        return winHeight >= rect.top;
      }
    }
  }, {
    key: "load",
    value: function load(event) {
      this.setState({
        loaded: true
      });

      if (this.props.onLoad) {
        this.props.onLoad(event);
      }
    }
  }, {
    key: "componentWillUnmount",
    value: function componentWillUnmount() {
      this.unbindScrollListener();
    }
  }, {
    key: "render",
    value: function render() {
      var _this3 = this;

      return /*#__PURE__*/_react.default.createElement("div", {
        ref: function ref(el) {
          return _this3.container = el;
        }
      }, this.state.loaded ? this.props.children : null);
    }
  }]);

  return DeferredContent;
}(_react.Component);

exports.DeferredContent = DeferredContent;

_defineProperty(DeferredContent, "defaultProps", {
  onload: null
});

_defineProperty(DeferredContent, "propTypes", {
  onLoad: _propTypes.default.func
});