@xiaoluxiaolu/react-scrollload/dist/Scrollload.js

react function component,achieve scrollload through IntersectionObserver

"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["default"] = void 0;

require("./ScrollLoad.css");

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

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 ownKeys(object, enumerableOnly) { var keys = Object.keys(object); if (Object.getOwnPropertySymbols) { var symbols = Object.getOwnPropertySymbols(object); if (enumerableOnly) symbols = symbols.filter(function (sym) { return Object.getOwnPropertyDescriptor(object, sym).enumerable; }); keys.push.apply(keys, symbols); } return keys; }

function _objectSpread(target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i] != null ? arguments[i] : {}; if (i % 2) { ownKeys(Object(source), true).forEach(function (key) { _defineProperty(target, key, source[key]); }); } else if (Object.getOwnPropertyDescriptors) { Object.defineProperties(target, Object.getOwnPropertyDescriptors(source)); } else { ownKeys(Object(source)).forEach(function (key) { Object.defineProperty(target, key, Object.getOwnPropertyDescriptor(source, key)); }); } } return target; }

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 _slicedToArray(arr, i) { return _arrayWithHoles(arr) || _iterableToArrayLimit(arr, i) || _unsupportedIterableToArray(arr, i) || _nonIterableRest(); }

function _nonIterableRest() { throw new TypeError("Invalid attempt to destructure non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); }

function _unsupportedIterableToArray(o, minLen) { if (!o) return; if (typeof o === "string") return _arrayLikeToArray(o, minLen); var n = Object.prototype.toString.call(o).slice(8, -1); if (n === "Object" && o.constructor) n = o.constructor.name; if (n === "Map" || n === "Set") return Array.from(o); if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen); }

function _arrayLikeToArray(arr, len) { if (len == null || len > arr.length) len = arr.length; for (var i = 0, arr2 = new Array(len); i < len; i++) { arr2[i] = arr[i]; } return arr2; }

function _iterableToArrayLimit(arr, i) { if (typeof Symbol === "undefined" || !(Symbol.iterator in Object(arr))) return; var _arr = []; var _n = true; var _d = false; var _e = undefined; try { for (var _i = arr[Symbol.iterator](), _s; !(_n = (_s = _i.next()).done); _n = true) { _arr.push(_s.value); if (i && _arr.length === i) break; } } catch (err) { _d = true; _e = err; } finally { try { if (!_n && _i["return"] != null) _i["return"](); } finally { if (_d) throw _e; } } return _arr; }

function _arrayWithHoles(arr) { if (Array.isArray(arr)) return arr; }

var ScrollLoad = function ScrollLoad(_ref) {
  var option = _ref.option,
      loadMoreFun = _ref.loadMoreFun,
      loadingContent = _ref.loadingContent;

  var _useState = (0, _react.useState)(false),
      _useState2 = _slicedToArray(_useState, 2),
      stop = _useState2[0],
      toggleStop = _useState2[1];

  var spinRef = (0, _react.useRef)(null);
  (0, _react.useEffect)(function () {
    var io = new IntersectionObserver(function (entries) {
      var entry = entries.find(function (item) {
        return item.target === spinRef.current;
      }); // 如果不可见，就不再请求数据

      if (!entry || !entry.isIntersecting) {
        return;
      }

      if (typeof loadMoreFun === 'function') {
        // 请求数据前停止观察，请求结束时再更具数据结果，看是否要继续监听
        io.unobserve(spinRef.current);
        Promise.resolve(loadMoreFun()).then(function (continuation) {
          var stop = continuation === false;
          toggleStop(stop);

          if (stop) {
            // 关闭观察器
            io.disconnect();
          } else {
            // 继续开启观察
            io.observe(spinRef.current);
          }
        })["catch"](function () {
          // 关闭观察器
          io.disconnect();
          toggleStop(true);
        });
      }
    }, _objectSpread({}, option));
    io.observe(spinRef.current);
    return function () {
      // 关闭观察器
      io && io.disconnect();
    };
  }, [loadMoreFun, option]);
  return /*#__PURE__*/_react["default"].createElement("div", {
    ref: spinRef,
    className: "tui-scrollLoad-spin"
  }, !stop && loadingContent);
};

ScrollLoad.defaultProps = {
  option: {},
  loadingContent: 'loading...'
};
var _default = ScrollLoad;
exports["default"] = _default;