@sullivan/react-virtualizer/lib/Virtual.js

Simple pseudo virtualization and reveal components to hide off-window components

"use strict";
var __assign = (this && this.__assign) || function () {
    __assign = Object.assign || function(t) {
        for (var s, i = 1, n = arguments.length; i < n; i++) {
            s = arguments[i];
            for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
                t[p] = s[p];
        }
        return t;
    };
    return __assign.apply(this, arguments);
};
var __rest = (this && this.__rest) || function (s, e) {
    var t = {};
    for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p) && e.indexOf(p) < 0)
        t[p] = s[p];
    if (s != null && typeof Object.getOwnPropertySymbols === "function")
        for (var i = 0, p = Object.getOwnPropertySymbols(s); i < p.length; i++) {
            if (e.indexOf(p[i]) < 0 && Object.prototype.propertyIsEnumerable.call(s, p[i]))
                t[p[i]] = s[p[i]];
        }
    return t;
};
var __importStar = (this && this.__importStar) || function (mod) {
    if (mod && mod.__esModule) return mod;
    var result = {};
    if (mod != null) for (var k in mod) if (Object.hasOwnProperty.call(mod, k)) result[k] = mod[k];
    result["default"] = mod;
    return result;
};
Object.defineProperty(exports, "__esModule", { value: true });
var react_1 = __importStar(require("react"));
require("./VirtualTypes");
var parseEntity = function (v) {
    if (Number.isInteger(v)) {
        return v + "px";
    }
    return v;
};
var Virtual = function (_a) {
    var children = _a.children, _b = _a.style, style = _b === void 0 ? {} : _b, _c = _a.tag, tag = _c === void 0 ? 'div' : _c, _d = _a.initialHeight, initialHeight = _d === void 0 ? '100vh' : _d, _e = _a.initialWidth, initialWidth = _e === void 0 ? '100vw' : _e, _f = _a.rootMargin, rootMargin = _f === void 0 ? '100px' : _f, props = __rest(_a, ["children", "style", "tag", "initialHeight", "initialWidth", "rootMargin"]);
    var _g = react_1.useState(false), vis = _g[0], setVis = _g[1];
    var _h = react_1.useState({ width: initialWidth, height: initialHeight }), dimesions = _h[0], setDimensions = _h[1];
    var ref = react_1.useRef();
    react_1.useEffect(function () {
        var obs = new IntersectionObserver(function (entries) {
            var entry = entries.pop();
            // @ts-ignore
            var visible = entry.isIntersecting;
            setVis(visible);
            if (!visible) {
                // @ts-ignore
                var bounds = entry.boundingClientRect;
                setDimensions({
                    // @ts-ignore
                    height: bounds.height,
                    // @ts-ignore
                    width: bounds.width,
                });
            }
        }, {
            root: null,
            rootMargin: parseEntity(rootMargin),
            threshold: [0],
        });
        // @ts-ignore
        obs.observe(ref.current);
        return function () { return obs.disconnect(); };
    }, []);
    return react_1.default.createElement(tag, __assign({}, props, { 
        // Use last known height to mimic space when not visible
        style: vis ? style : __assign({}, style, dimesions), ref: ref }), vis ? children : []);
};
exports.default = Virtual;