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@enykeev/react-virtualized

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React components for efficiently rendering large, scrollable lists and tabular data

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"use strict"; var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault"); Object.defineProperty(exports, "__esModule", { value: true }); exports["default"] = void 0; var _slicedToArray2 = _interopRequireDefault(require("@babel/runtime/helpers/slicedToArray")); var _classCallCheck2 = _interopRequireDefault(require("@babel/runtime/helpers/classCallCheck")); var _createClass2 = _interopRequireDefault(require("@babel/runtime/helpers/createClass")); var _defineProperty2 = _interopRequireDefault(require("@babel/runtime/helpers/defineProperty")); var _intervalTree = _interopRequireDefault(require("../vendor/intervalTree")); // Position cache requirements: // O(log(n)) lookup of cells to render for a given viewport size // O(1) lookup of shortest measured column (so we know when to enter phase 1) var PositionCache = /*#__PURE__*/ function () { function PositionCache() { (0, _classCallCheck2["default"])(this, PositionCache); (0, _defineProperty2["default"])(this, "_columnSizeMap", {}); (0, _defineProperty2["default"])(this, "_intervalTree", (0, _intervalTree["default"])()); (0, _defineProperty2["default"])(this, "_leftMap", {}); } (0, _createClass2["default"])(PositionCache, [{ key: "estimateTotalHeight", value: function estimateTotalHeight(cellCount /*: number*/ , columnCount /*: number*/ , defaultCellHeight /*: number*/ ) /*: number*/ { var unmeasuredCellCount = cellCount - this.count; return this.tallestColumnSize + Math.ceil(unmeasuredCellCount / columnCount) * defaultCellHeight; } // Render all cells visible within the viewport range defined. }, { key: "range", value: function range(scrollTop /*: number*/ , clientHeight /*: number*/ , renderCallback /*: RenderCallback*/ ) /*: void*/ { var _this = this; this._intervalTree.queryInterval(scrollTop, scrollTop + clientHeight, function (_ref) { var _ref2 = (0, _slicedToArray2["default"])(_ref, 3), top = _ref2[0], _ = _ref2[1], index = _ref2[2]; return renderCallback(index, _this._leftMap[index], top); }); } }, { key: "setPosition", value: function setPosition(index /*: number*/ , left /*: number*/ , top /*: number*/ , height /*: number*/ ) /*: void*/ { this._intervalTree.insert([top, top + height, index]); this._leftMap[index] = left; var columnSizeMap = this._columnSizeMap; var columnHeight = columnSizeMap[left]; if (columnHeight === undefined) { columnSizeMap[left] = top + height; } else { columnSizeMap[left] = Math.max(columnHeight, top + height); } } }, { key: "count", get: function get() /*: number*/ { return this._intervalTree.count; } }, { key: "shortestColumnSize", get: function get() /*: number*/ { var columnSizeMap = this._columnSizeMap; var size = 0; for (var i in columnSizeMap) { var height = columnSizeMap[(i /*: any*/ )]; size = size === 0 ? height : Math.min(size, height); } return size; } }, { key: "tallestColumnSize", get: function get() /*: number*/ { var columnSizeMap = this._columnSizeMap; var size = 0; for (var i in columnSizeMap) { var height = columnSizeMap[(i /*: any*/ )]; size = Math.max(size, height); } return size; } }]); return PositionCache; }(); exports["default"] = PositionCache;