@juggle/resize-observer
Version:
Polyfills the ResizeObserver API and supports box size options from the latest spec
513 lines (486 loc) • 21.3 kB
JavaScript
(function (global, factory) {
typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
typeof define === 'function' && define.amd ? define(['exports'], factory) :
(global = typeof globalThis !== 'undefined' ? globalThis : global || self, factory(global.ResizeObserver = {}));
})(this, (function (exports) { 'use strict';
var resizeObservers = [];
var hasActiveObservations = function () {
return resizeObservers.some(function (ro) { return ro.activeTargets.length > 0; });
};
var hasSkippedObservations = function () {
return resizeObservers.some(function (ro) { return ro.skippedTargets.length > 0; });
};
var msg = 'ResizeObserver loop completed with undelivered notifications.';
var deliverResizeLoopError = function () {
var event;
if (typeof ErrorEvent === 'function') {
event = new ErrorEvent('error', {
message: msg
});
}
else {
event = document.createEvent('Event');
event.initEvent('error', false, false);
event.message = msg;
}
window.dispatchEvent(event);
};
var ResizeObserverBoxOptions;
(function (ResizeObserverBoxOptions) {
ResizeObserverBoxOptions["BORDER_BOX"] = "border-box";
ResizeObserverBoxOptions["CONTENT_BOX"] = "content-box";
ResizeObserverBoxOptions["DEVICE_PIXEL_CONTENT_BOX"] = "device-pixel-content-box";
})(ResizeObserverBoxOptions || (ResizeObserverBoxOptions = {}));
var freeze = function (obj) { return Object.freeze(obj); };
var ResizeObserverSize = (function () {
function ResizeObserverSize(inlineSize, blockSize) {
this.inlineSize = inlineSize;
this.blockSize = blockSize;
freeze(this);
}
return ResizeObserverSize;
}());
var DOMRectReadOnly = (function () {
function DOMRectReadOnly(x, y, width, height) {
this.x = x;
this.y = y;
this.width = width;
this.height = height;
this.top = this.y;
this.left = this.x;
this.bottom = this.top + this.height;
this.right = this.left + this.width;
return freeze(this);
}
DOMRectReadOnly.prototype.toJSON = function () {
var _a = this, x = _a.x, y = _a.y, top = _a.top, right = _a.right, bottom = _a.bottom, left = _a.left, width = _a.width, height = _a.height;
return { x: x, y: y, top: top, right: right, bottom: bottom, left: left, width: width, height: height };
};
DOMRectReadOnly.fromRect = function (rectangle) {
return new DOMRectReadOnly(rectangle.x, rectangle.y, rectangle.width, rectangle.height);
};
return DOMRectReadOnly;
}());
var isSVG = function (target) { return target instanceof SVGElement && 'getBBox' in target; };
var isHidden = function (target) {
if (isSVG(target)) {
var _a = target.getBBox(), width = _a.width, height = _a.height;
return !width && !height;
}
var _b = target, offsetWidth = _b.offsetWidth, offsetHeight = _b.offsetHeight;
return !(offsetWidth || offsetHeight || target.getClientRects().length);
};
var isElement = function (obj) {
var _a;
if (obj instanceof Element) {
return true;
}
var scope = (_a = obj === null || obj === void 0 ? void 0 : obj.ownerDocument) === null || _a === void 0 ? void 0 : _a.defaultView;
return !!(scope && obj instanceof scope.Element);
};
var isReplacedElement = function (target) {
switch (target.tagName) {
case 'INPUT':
if (target.type !== 'image') {
break;
}
case 'VIDEO':
case 'AUDIO':
case 'EMBED':
case 'OBJECT':
case 'CANVAS':
case 'IFRAME':
case 'IMG':
return true;
}
return false;
};
var global = typeof window !== 'undefined' ? window : {};
var cache = new WeakMap();
var scrollRegexp = /auto|scroll/;
var verticalRegexp = /^tb|vertical/;
var IE = (/msie|trident/i).test(global.navigator && global.navigator.userAgent);
var parseDimension = function (pixel) { return parseFloat(pixel || '0'); };
var size = function (inlineSize, blockSize, switchSizes) {
if (inlineSize === void 0) { inlineSize = 0; }
if (blockSize === void 0) { blockSize = 0; }
if (switchSizes === void 0) { switchSizes = false; }
return new ResizeObserverSize((switchSizes ? blockSize : inlineSize) || 0, (switchSizes ? inlineSize : blockSize) || 0);
};
var zeroBoxes = freeze({
devicePixelContentBoxSize: size(),
borderBoxSize: size(),
contentBoxSize: size(),
contentRect: new DOMRectReadOnly(0, 0, 0, 0)
});
var calculateBoxSizes = function (target, forceRecalculation) {
if (forceRecalculation === void 0) { forceRecalculation = false; }
if (cache.has(target) && !forceRecalculation) {
return cache.get(target);
}
if (isHidden(target)) {
cache.set(target, zeroBoxes);
return zeroBoxes;
}
var cs = getComputedStyle(target);
var svg = isSVG(target) && target.ownerSVGElement && target.getBBox();
var removePadding = !IE && cs.boxSizing === 'border-box';
var switchSizes = verticalRegexp.test(cs.writingMode || '');
var canScrollVertically = !svg && scrollRegexp.test(cs.overflowY || '');
var canScrollHorizontally = !svg && scrollRegexp.test(cs.overflowX || '');
var paddingTop = svg ? 0 : parseDimension(cs.paddingTop);
var paddingRight = svg ? 0 : parseDimension(cs.paddingRight);
var paddingBottom = svg ? 0 : parseDimension(cs.paddingBottom);
var paddingLeft = svg ? 0 : parseDimension(cs.paddingLeft);
var borderTop = svg ? 0 : parseDimension(cs.borderTopWidth);
var borderRight = svg ? 0 : parseDimension(cs.borderRightWidth);
var borderBottom = svg ? 0 : parseDimension(cs.borderBottomWidth);
var borderLeft = svg ? 0 : parseDimension(cs.borderLeftWidth);
var horizontalPadding = paddingLeft + paddingRight;
var verticalPadding = paddingTop + paddingBottom;
var horizontalBorderArea = borderLeft + borderRight;
var verticalBorderArea = borderTop + borderBottom;
var horizontalScrollbarThickness = !canScrollHorizontally ? 0 : target.offsetHeight - verticalBorderArea - target.clientHeight;
var verticalScrollbarThickness = !canScrollVertically ? 0 : target.offsetWidth - horizontalBorderArea - target.clientWidth;
var widthReduction = removePadding ? horizontalPadding + horizontalBorderArea : 0;
var heightReduction = removePadding ? verticalPadding + verticalBorderArea : 0;
var contentWidth = svg ? svg.width : parseDimension(cs.width) - widthReduction - verticalScrollbarThickness;
var contentHeight = svg ? svg.height : parseDimension(cs.height) - heightReduction - horizontalScrollbarThickness;
var borderBoxWidth = contentWidth + horizontalPadding + verticalScrollbarThickness + horizontalBorderArea;
var borderBoxHeight = contentHeight + verticalPadding + horizontalScrollbarThickness + verticalBorderArea;
var boxes = freeze({
devicePixelContentBoxSize: size(Math.round(contentWidth * devicePixelRatio), Math.round(contentHeight * devicePixelRatio), switchSizes),
borderBoxSize: size(borderBoxWidth, borderBoxHeight, switchSizes),
contentBoxSize: size(contentWidth, contentHeight, switchSizes),
contentRect: new DOMRectReadOnly(paddingLeft, paddingTop, contentWidth, contentHeight)
});
cache.set(target, boxes);
return boxes;
};
var calculateBoxSize = function (target, observedBox, forceRecalculation) {
var _a = calculateBoxSizes(target, forceRecalculation), borderBoxSize = _a.borderBoxSize, contentBoxSize = _a.contentBoxSize, devicePixelContentBoxSize = _a.devicePixelContentBoxSize;
switch (observedBox) {
case ResizeObserverBoxOptions.DEVICE_PIXEL_CONTENT_BOX:
return devicePixelContentBoxSize;
case ResizeObserverBoxOptions.BORDER_BOX:
return borderBoxSize;
default:
return contentBoxSize;
}
};
var ResizeObserverEntry = (function () {
function ResizeObserverEntry(target) {
var boxes = calculateBoxSizes(target);
this.target = target;
this.contentRect = boxes.contentRect;
this.borderBoxSize = freeze([boxes.borderBoxSize]);
this.contentBoxSize = freeze([boxes.contentBoxSize]);
this.devicePixelContentBoxSize = freeze([boxes.devicePixelContentBoxSize]);
}
return ResizeObserverEntry;
}());
var calculateDepthForNode = function (node) {
if (isHidden(node)) {
return Infinity;
}
var depth = 0;
var parent = node.parentNode;
while (parent) {
depth += 1;
parent = parent.parentNode;
}
return depth;
};
var broadcastActiveObservations = function () {
var shallowestDepth = Infinity;
var callbacks = [];
resizeObservers.forEach(function processObserver(ro) {
if (ro.activeTargets.length === 0) {
return;
}
var entries = [];
ro.activeTargets.forEach(function processTarget(ot) {
var entry = new ResizeObserverEntry(ot.target);
var targetDepth = calculateDepthForNode(ot.target);
entries.push(entry);
ot.lastReportedSize = calculateBoxSize(ot.target, ot.observedBox);
if (targetDepth < shallowestDepth) {
shallowestDepth = targetDepth;
}
});
callbacks.push(function resizeObserverCallback() {
ro.callback.call(ro.observer, entries, ro.observer);
});
ro.activeTargets.splice(0, ro.activeTargets.length);
});
for (var _i = 0, callbacks_1 = callbacks; _i < callbacks_1.length; _i++) {
var callback = callbacks_1[_i];
callback();
}
return shallowestDepth;
};
var gatherActiveObservationsAtDepth = function (depth) {
resizeObservers.forEach(function processObserver(ro) {
ro.activeTargets.splice(0, ro.activeTargets.length);
ro.skippedTargets.splice(0, ro.skippedTargets.length);
ro.observationTargets.forEach(function processTarget(ot) {
if (ot.isActive()) {
if (calculateDepthForNode(ot.target) > depth) {
ro.activeTargets.push(ot);
}
else {
ro.skippedTargets.push(ot);
}
}
});
});
};
var process = function () {
var depth = 0;
gatherActiveObservationsAtDepth(depth);
while (hasActiveObservations()) {
depth = broadcastActiveObservations();
gatherActiveObservationsAtDepth(depth);
}
if (hasSkippedObservations()) {
deliverResizeLoopError();
}
return depth > 0;
};
var trigger;
var callbacks = [];
var notify = function () { return callbacks.splice(0).forEach(function (cb) { return cb(); }); };
var queueMicroTask = function (callback) {
if (!trigger) {
var toggle_1 = 0;
var el_1 = document.createTextNode('');
var config = { characterData: true };
new MutationObserver(function () { return notify(); }).observe(el_1, config);
trigger = function () { el_1.textContent = "".concat(toggle_1 ? toggle_1-- : toggle_1++); };
}
callbacks.push(callback);
trigger();
};
var queueResizeObserver = function (cb) {
queueMicroTask(function ResizeObserver() {
requestAnimationFrame(cb);
});
};
var watching = 0;
var isWatching = function () { return !!watching; };
var CATCH_PERIOD = 250;
var observerConfig = { attributes: true, characterData: true, childList: true, subtree: true };
var events = [
'resize',
'load',
'transitionend',
'animationend',
'animationstart',
'animationiteration',
'keyup',
'keydown',
'mouseup',
'mousedown',
'mouseover',
'mouseout',
'blur',
'focus'
];
var time = function (timeout) {
if (timeout === void 0) { timeout = 0; }
return Date.now() + timeout;
};
var scheduled = false;
var Scheduler = (function () {
function Scheduler() {
var _this = this;
this.stopped = true;
this.listener = function () { return _this.schedule(); };
}
Scheduler.prototype.run = function (timeout) {
var _this = this;
if (timeout === void 0) { timeout = CATCH_PERIOD; }
if (scheduled) {
return;
}
scheduled = true;
var until = time(timeout);
queueResizeObserver(function () {
var elementsHaveResized = false;
try {
elementsHaveResized = process();
}
finally {
scheduled = false;
timeout = until - time();
if (!isWatching()) {
return;
}
if (elementsHaveResized) {
_this.run(1000);
}
else if (timeout > 0) {
_this.run(timeout);
}
else {
_this.start();
}
}
});
};
Scheduler.prototype.schedule = function () {
this.stop();
this.run();
};
Scheduler.prototype.observe = function () {
var _this = this;
var cb = function () { return _this.observer && _this.observer.observe(document.body, observerConfig); };
document.body ? cb() : global.addEventListener('DOMContentLoaded', cb);
};
Scheduler.prototype.start = function () {
var _this = this;
if (this.stopped) {
this.stopped = false;
this.observer = new MutationObserver(this.listener);
this.observe();
events.forEach(function (name) { return global.addEventListener(name, _this.listener, true); });
}
};
Scheduler.prototype.stop = function () {
var _this = this;
if (!this.stopped) {
this.observer && this.observer.disconnect();
events.forEach(function (name) { return global.removeEventListener(name, _this.listener, true); });
this.stopped = true;
}
};
return Scheduler;
}());
var scheduler = new Scheduler();
var updateCount = function (n) {
!watching && n > 0 && scheduler.start();
watching += n;
!watching && scheduler.stop();
};
var skipNotifyOnElement = function (target) {
return !isSVG(target)
&& !isReplacedElement(target)
&& getComputedStyle(target).display === 'inline';
};
var ResizeObservation = (function () {
function ResizeObservation(target, observedBox) {
this.target = target;
this.observedBox = observedBox || ResizeObserverBoxOptions.CONTENT_BOX;
this.lastReportedSize = {
inlineSize: 0,
blockSize: 0
};
}
ResizeObservation.prototype.isActive = function () {
var size = calculateBoxSize(this.target, this.observedBox, true);
if (skipNotifyOnElement(this.target)) {
this.lastReportedSize = size;
}
if (this.lastReportedSize.inlineSize !== size.inlineSize
|| this.lastReportedSize.blockSize !== size.blockSize) {
return true;
}
return false;
};
return ResizeObservation;
}());
var ResizeObserverDetail = (function () {
function ResizeObserverDetail(resizeObserver, callback) {
this.activeTargets = [];
this.skippedTargets = [];
this.observationTargets = [];
this.observer = resizeObserver;
this.callback = callback;
}
return ResizeObserverDetail;
}());
var observerMap = new WeakMap();
var getObservationIndex = function (observationTargets, target) {
for (var i = 0; i < observationTargets.length; i += 1) {
if (observationTargets[i].target === target) {
return i;
}
}
return -1;
};
var ResizeObserverController = (function () {
function ResizeObserverController() {
}
ResizeObserverController.connect = function (resizeObserver, callback) {
var detail = new ResizeObserverDetail(resizeObserver, callback);
observerMap.set(resizeObserver, detail);
};
ResizeObserverController.observe = function (resizeObserver, target, options) {
var detail = observerMap.get(resizeObserver);
var firstObservation = detail.observationTargets.length === 0;
if (getObservationIndex(detail.observationTargets, target) < 0) {
firstObservation && resizeObservers.push(detail);
detail.observationTargets.push(new ResizeObservation(target, options && options.box));
updateCount(1);
scheduler.schedule();
}
};
ResizeObserverController.unobserve = function (resizeObserver, target) {
var detail = observerMap.get(resizeObserver);
var index = getObservationIndex(detail.observationTargets, target);
var lastObservation = detail.observationTargets.length === 1;
if (index >= 0) {
lastObservation && resizeObservers.splice(resizeObservers.indexOf(detail), 1);
detail.observationTargets.splice(index, 1);
updateCount(-1);
}
};
ResizeObserverController.disconnect = function (resizeObserver) {
var _this = this;
var detail = observerMap.get(resizeObserver);
detail.observationTargets.slice().forEach(function (ot) { return _this.unobserve(resizeObserver, ot.target); });
detail.activeTargets.splice(0, detail.activeTargets.length);
};
return ResizeObserverController;
}());
var ResizeObserver = (function () {
function ResizeObserver(callback) {
if (arguments.length === 0) {
throw new TypeError("Failed to construct 'ResizeObserver': 1 argument required, but only 0 present.");
}
if (typeof callback !== 'function') {
throw new TypeError("Failed to construct 'ResizeObserver': The callback provided as parameter 1 is not a function.");
}
ResizeObserverController.connect(this, callback);
}
ResizeObserver.prototype.observe = function (target, options) {
if (arguments.length === 0) {
throw new TypeError("Failed to execute 'observe' on 'ResizeObserver': 1 argument required, but only 0 present.");
}
if (!isElement(target)) {
throw new TypeError("Failed to execute 'observe' on 'ResizeObserver': parameter 1 is not of type 'Element");
}
ResizeObserverController.observe(this, target, options);
};
ResizeObserver.prototype.unobserve = function (target) {
if (arguments.length === 0) {
throw new TypeError("Failed to execute 'unobserve' on 'ResizeObserver': 1 argument required, but only 0 present.");
}
if (!isElement(target)) {
throw new TypeError("Failed to execute 'unobserve' on 'ResizeObserver': parameter 1 is not of type 'Element");
}
ResizeObserverController.unobserve(this, target);
};
ResizeObserver.prototype.disconnect = function () {
ResizeObserverController.disconnect(this);
};
ResizeObserver.toString = function () {
return 'function ResizeObserver () { [polyfill code] }';
};
return ResizeObserver;
}());
exports.ResizeObserver = ResizeObserver;
exports.ResizeObserverEntry = ResizeObserverEntry;
exports.ResizeObserverSize = ResizeObserverSize;
Object.defineProperty(exports, '__esModule', { value: true });
}));