1224 lines
39 KiB
JavaScript
1224 lines
39 KiB
JavaScript
(function (global, factory) {
|
|
typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory(require('react')) :
|
|
typeof define === 'function' && define.amd ? define(['react'], factory) :
|
|
(global = global || self, global.useIntersectionObserver = factory(global.React));
|
|
}(this, (function (React) { 'use strict';
|
|
|
|
function _objectWithoutPropertiesLoose(source, excluded) {
|
|
if (source == null) return {};
|
|
var target = {};
|
|
var sourceKeys = Object.keys(source);
|
|
var key, i;
|
|
|
|
for (i = 0; i < sourceKeys.length; i++) {
|
|
key = sourceKeys[i];
|
|
if (excluded.indexOf(key) >= 0) continue;
|
|
target[key] = source[key];
|
|
}
|
|
|
|
return target;
|
|
}
|
|
|
|
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 _createForOfIteratorHelperLoose(o, allowArrayLike) {
|
|
var it;
|
|
|
|
if (typeof Symbol === "undefined" || o[Symbol.iterator] == null) {
|
|
if (Array.isArray(o) || (it = _unsupportedIterableToArray(o)) || allowArrayLike && o && typeof o.length === "number") {
|
|
if (it) o = it;
|
|
var i = 0;
|
|
return function () {
|
|
if (i >= o.length) return {
|
|
done: true
|
|
};
|
|
return {
|
|
done: false,
|
|
value: o[i++]
|
|
};
|
|
};
|
|
}
|
|
|
|
throw new TypeError("Invalid attempt to iterate non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method.");
|
|
}
|
|
|
|
it = o[Symbol.iterator]();
|
|
return it.next.bind(it);
|
|
}
|
|
|
|
function _get() {
|
|
return this.intersectionRatio > 0;
|
|
}
|
|
|
|
function _ref(margin) {
|
|
return margin.value + margin.unit;
|
|
}
|
|
|
|
function _ref2(observer) {
|
|
observer._checkForIntersections();
|
|
}
|
|
|
|
function _ref3(target) {
|
|
var isTargetAlreadyObserved = this._observationTargets.some(function (item) {
|
|
return item.element == target;
|
|
});
|
|
|
|
if (isTargetAlreadyObserved) {
|
|
return;
|
|
}
|
|
|
|
if (!(target && target.nodeType == 1)) {
|
|
throw new Error('target must be an Element');
|
|
}
|
|
|
|
this._registerInstance();
|
|
|
|
this._observationTargets.push({
|
|
element: target,
|
|
entry: null
|
|
});
|
|
|
|
this._monitorIntersections(target.ownerDocument);
|
|
|
|
this._checkForIntersections();
|
|
}
|
|
|
|
function _ref4(target) {
|
|
this._observationTargets = this._observationTargets.filter(function (item) {
|
|
return item.element != target;
|
|
});
|
|
|
|
this._unmonitorIntersections(target.ownerDocument);
|
|
|
|
if (this._observationTargets.length == 0) {
|
|
this._unregisterInstance();
|
|
}
|
|
}
|
|
|
|
function _ref5() {
|
|
this._observationTargets = [];
|
|
|
|
this._unmonitorAllIntersections();
|
|
|
|
this._unregisterInstance();
|
|
}
|
|
|
|
function _ref6() {
|
|
var records = this._queuedEntries.slice();
|
|
|
|
this._queuedEntries = [];
|
|
return records;
|
|
}
|
|
|
|
function _ref7(t, i, a) {
|
|
if (typeof t != 'number' || isNaN(t) || t < 0 || t > 1) {
|
|
throw new Error('threshold must be a number between 0 and 1 inclusively');
|
|
}
|
|
|
|
return t !== a[i - 1];
|
|
}
|
|
|
|
function _ref8(opt_threshold) {
|
|
var threshold = opt_threshold || [0];
|
|
if (!Array.isArray(threshold)) threshold = [threshold];
|
|
return threshold.sort().filter(_ref7);
|
|
}
|
|
|
|
function _ref9(margin) {
|
|
var parts = /^(-?\d*\.?\d+)(px|%)$/.exec(margin);
|
|
|
|
if (!parts) {
|
|
throw new Error('rootMargin must be specified in pixels or percent');
|
|
}
|
|
|
|
return {
|
|
value: parseFloat(parts[1]),
|
|
unit: parts[2]
|
|
};
|
|
}
|
|
|
|
function _ref10(opt_rootMargin) {
|
|
var marginString = opt_rootMargin || '0px';
|
|
var margins = marginString.split(/\s+/).map(_ref9); // Handles shorthand.
|
|
|
|
margins[1] = margins[1] || margins[0];
|
|
margins[2] = margins[2] || margins[0];
|
|
margins[3] = margins[3] || margins[1];
|
|
return margins;
|
|
}
|
|
|
|
function _ref11() {
|
|
var unsubscribes = this._monitoringUnsubscribes.slice(0);
|
|
|
|
this._monitoringDocuments.length = 0;
|
|
this._monitoringUnsubscribes.length = 0;
|
|
|
|
for (var i = 0; i < unsubscribes.length; i++) {
|
|
unsubscribes[i]();
|
|
}
|
|
}
|
|
|
|
function _ref12(rect) {
|
|
var margins = this._rootMarginValues.map(function (margin, i) {
|
|
return margin.unit == 'px' ? margin.value : margin.value * (i % 2 ? rect.width : rect.height) / 100;
|
|
});
|
|
|
|
var newRect = {
|
|
top: rect.top - margins[0],
|
|
right: rect.right + margins[1],
|
|
bottom: rect.bottom + margins[2],
|
|
left: rect.left - margins[3]
|
|
};
|
|
newRect.width = newRect.right - newRect.left;
|
|
newRect.height = newRect.bottom - newRect.top;
|
|
return newRect;
|
|
}
|
|
|
|
function _ref13(oldEntry, newEntry) {
|
|
// To make comparing easier, an entry that has a ratio of 0
|
|
// but does not actually intersect is given a value of -1
|
|
var oldRatio = oldEntry && oldEntry.isIntersecting ? oldEntry.intersectionRatio || 0 : -1;
|
|
var newRatio = newEntry.isIntersecting ? newEntry.intersectionRatio || 0 : -1; // Ignore unchanged ratios
|
|
|
|
if (oldRatio === newRatio) return;
|
|
|
|
for (var i = 0; i < this.thresholds.length; i++) {
|
|
var threshold = this.thresholds[i]; // Return true if an entry matches a threshold or if the new ratio
|
|
// and the old ratio are on the opposite sides of a threshold.
|
|
|
|
if (threshold == oldRatio || threshold == newRatio || threshold < oldRatio !== threshold < newRatio) {
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Returns the result of the performance.now() method or null in browsers
|
|
* that don't support the API.
|
|
* @return {number} The elapsed time since the page was requested.
|
|
*/
|
|
function now() {
|
|
return window.performance && performance.now && performance.now();
|
|
}
|
|
/**
|
|
* Throttles a function and delays its execution, so it's only called at most
|
|
* once within a given time period.
|
|
* @param {Function} fn The function to throttle.
|
|
* @param {number} timeout The amount of time that must pass before the
|
|
* function can be called again.
|
|
* @return {Function} The throttled function.
|
|
*/
|
|
|
|
|
|
function throttle(fn, timeout) {
|
|
var timer = null;
|
|
|
|
function _ref14() {
|
|
fn();
|
|
timer = null;
|
|
}
|
|
|
|
return function () {
|
|
if (!timer) {
|
|
timer = setTimeout(_ref14, timeout);
|
|
}
|
|
};
|
|
}
|
|
/**
|
|
* Adds an event handler to a DOM node ensuring cross-browser compatibility.
|
|
* @param {Node} node The DOM node to add the event handler to.
|
|
* @param {string} event The event name.
|
|
* @param {Function} fn The event handler to add.
|
|
* @param {boolean} opt_useCapture Optionally adds the even to the capture
|
|
* phase. Note: this only works in modern browsers.
|
|
*/
|
|
|
|
|
|
function addEvent(node, event, fn, opt_useCapture) {
|
|
if (typeof node.addEventListener == 'function') {
|
|
node.addEventListener(event, fn, opt_useCapture || false);
|
|
} else if (typeof node.attachEvent == 'function') {
|
|
node.attachEvent('on' + event, fn);
|
|
}
|
|
}
|
|
/**
|
|
* Removes a previously added event handler from a DOM node.
|
|
* @param {Node} node The DOM node to remove the event handler from.
|
|
* @param {string} event The event name.
|
|
* @param {Function} fn The event handler to remove.
|
|
* @param {boolean} opt_useCapture If the event handler was added with this
|
|
* flag set to true, it should be set to true here in order to remove it.
|
|
*/
|
|
|
|
|
|
function removeEvent(node, event, fn, opt_useCapture) {
|
|
if (typeof node.removeEventListener == 'function') {
|
|
node.removeEventListener(event, fn, opt_useCapture || false);
|
|
} else if (typeof node.detatchEvent == 'function') {
|
|
node.detatchEvent('on' + event, fn);
|
|
}
|
|
}
|
|
/**
|
|
* Returns the intersection between two rect objects.
|
|
* @param {Object} rect1 The first rect.
|
|
* @param {Object} rect2 The second rect.
|
|
* @return {?Object|?ClientRect} The intersection rect or undefined if no
|
|
* intersection is found.
|
|
*/
|
|
|
|
|
|
function computeRectIntersection(rect1, rect2) {
|
|
var top = Math.max(rect1.top, rect2.top);
|
|
var bottom = Math.min(rect1.bottom, rect2.bottom);
|
|
var left = Math.max(rect1.left, rect2.left);
|
|
var right = Math.min(rect1.right, rect2.right);
|
|
var width = right - left;
|
|
var height = bottom - top;
|
|
return width >= 0 && height >= 0 && {
|
|
top: top,
|
|
bottom: bottom,
|
|
left: left,
|
|
right: right,
|
|
width: width,
|
|
height: height
|
|
} || null;
|
|
}
|
|
/**
|
|
* Shims the native getBoundingClientRect for compatibility with older IE.
|
|
* @param {Element} el The element whose bounding rect to get.
|
|
* @return {DOMRect|ClientRect} The (possibly shimmed) rect of the element.
|
|
*/
|
|
|
|
|
|
/**
|
|
* Returns an empty rect object. An empty rect is returned when an element
|
|
* is not in the DOM.
|
|
* @return {ClientRect} The empty rect.
|
|
*/
|
|
function getEmptyRect() {
|
|
return {
|
|
top: 0,
|
|
bottom: 0,
|
|
left: 0,
|
|
right: 0,
|
|
width: 0,
|
|
height: 0
|
|
};
|
|
}
|
|
/**
|
|
* Ensure that the result has all of the necessary fields of the DOMRect.
|
|
* Specifically this ensures that `x` and `y` fields are set.
|
|
*
|
|
* @param {?DOMRect|?ClientRect} rect
|
|
* @return {?DOMRect}
|
|
*/
|
|
|
|
|
|
function ensureDOMRect(rect) {
|
|
// A `DOMRect` object has `x` and `y` fields.
|
|
if (!rect || 'x' in rect) {
|
|
return rect;
|
|
} // A IE's `ClientRect` type does not have `x` and `y`. The same is the case
|
|
// for internally calculated Rect objects. For the purposes of
|
|
// `IntersectionObserver`, it's sufficient to simply mirror `left` and `top`
|
|
// for these fields.
|
|
|
|
|
|
return {
|
|
top: rect.top,
|
|
y: rect.top,
|
|
bottom: rect.bottom,
|
|
left: rect.left,
|
|
x: rect.left,
|
|
right: rect.right,
|
|
width: rect.width,
|
|
height: rect.height
|
|
};
|
|
}
|
|
/**
|
|
* Inverts the intersection and bounding rect from the parent (frame) BCR to
|
|
* the local BCR space.
|
|
* @param {DOMRect|ClientRect} parentBoundingRect The parent's bound client rect.
|
|
* @param {DOMRect|ClientRect} parentIntersectionRect The parent's own intersection rect.
|
|
* @return {ClientRect} The local root bounding rect for the parent's children.
|
|
*/
|
|
|
|
|
|
function convertFromParentRect(parentBoundingRect, parentIntersectionRect) {
|
|
var top = parentIntersectionRect.top - parentBoundingRect.top;
|
|
var left = parentIntersectionRect.left - parentBoundingRect.left;
|
|
return {
|
|
top: top,
|
|
left: left,
|
|
height: parentIntersectionRect.height,
|
|
width: parentIntersectionRect.width,
|
|
bottom: top + parentIntersectionRect.height,
|
|
right: left + parentIntersectionRect.width
|
|
};
|
|
}
|
|
/**
|
|
* Checks to see if a parent element contains a child element (including inside
|
|
* shadow DOM).
|
|
* @param {Node} parent The parent element.
|
|
* @param {Node} child The child element.
|
|
* @return {boolean} True if the parent node contains the child node.
|
|
*/
|
|
|
|
|
|
/**
|
|
* Returns the embedding frame element, if any.
|
|
* @param {!Document} doc
|
|
* @return {!Element}
|
|
*/
|
|
function getFrameElement(doc) {
|
|
try {
|
|
return doc.defaultView && doc.defaultView.frameElement || null;
|
|
} catch (e) {
|
|
// Ignore the error.
|
|
return null;
|
|
}
|
|
} // Exposes the constructors globally.
|
|
|
|
|
|
/**
|
|
* Copyright 2016 Google Inc. All Rights Reserved.
|
|
*
|
|
* Licensed under the W3C SOFTWARE AND DOCUMENT NOTICE AND LICENSE.
|
|
*
|
|
* https://www.w3.org/Consortium/Legal/2015/copyright-software-and-document
|
|
*
|
|
*/
|
|
(function () {
|
|
|
|
if (typeof window !== 'object') {
|
|
return;
|
|
} // Exit early if all IntersectionObserver and IntersectionObserverEntry
|
|
// features are natively supported.
|
|
|
|
|
|
if ('IntersectionObserver' in window && 'IntersectionObserverEntry' in window && 'intersectionRatio' in window.IntersectionObserverEntry.prototype) {
|
|
// Minimal polyfill for Edge 15's lack of `isIntersecting`
|
|
// See: https://github.com/w3c/IntersectionObserver/issues/211
|
|
if (!('isIntersecting' in window.IntersectionObserverEntry.prototype)) {
|
|
Object.defineProperty(window.IntersectionObserverEntry.prototype, 'isIntersecting', {
|
|
get: _get
|
|
});
|
|
}
|
|
|
|
return;
|
|
}
|
|
/**
|
|
* A local reference to the document.
|
|
*/
|
|
|
|
|
|
var document = window.document;
|
|
/**
|
|
* An IntersectionObserver registry. This registry exists to hold a strong
|
|
* reference to IntersectionObserver instances currently observing a target
|
|
* element. Without this registry, instances without another reference may be
|
|
* garbage collected.
|
|
*/
|
|
|
|
var registry = [];
|
|
/**
|
|
* The signal updater for cross-origin intersection. When not null, it means
|
|
* that the polyfill is configured to work in a cross-origin mode.
|
|
* @type {function(DOMRect|ClientRect, DOMRect|ClientRect)}
|
|
*/
|
|
|
|
var crossOriginUpdater = null;
|
|
/**
|
|
* The current cross-origin intersection. Only used in the cross-origin mode.
|
|
* @type {DOMRect|ClientRect}
|
|
*/
|
|
|
|
var crossOriginRect = null;
|
|
/**
|
|
* Creates the global IntersectionObserverEntry constructor.
|
|
* https://w3c.github.io/IntersectionObserver/#intersection-observer-entry
|
|
* @param {Object} entry A dictionary of instance properties.
|
|
* @constructor
|
|
*/
|
|
|
|
function IntersectionObserverEntry(entry) {
|
|
this.time = entry.time;
|
|
this.target = entry.target;
|
|
this.rootBounds = ensureDOMRect(entry.rootBounds);
|
|
this.boundingClientRect = ensureDOMRect(entry.boundingClientRect);
|
|
this.intersectionRect = ensureDOMRect(entry.intersectionRect || getEmptyRect());
|
|
this.isIntersecting = !!entry.intersectionRect; // Calculates the intersection ratio.
|
|
|
|
var targetRect = this.boundingClientRect;
|
|
var targetArea = targetRect.width * targetRect.height;
|
|
var intersectionRect = this.intersectionRect;
|
|
var intersectionArea = intersectionRect.width * intersectionRect.height; // Sets intersection ratio.
|
|
|
|
if (targetArea) {
|
|
// Round the intersection ratio to avoid floating point math issues:
|
|
// https://github.com/w3c/IntersectionObserver/issues/324
|
|
this.intersectionRatio = Number((intersectionArea / targetArea).toFixed(4));
|
|
} else {
|
|
// If area is zero and is intersecting, sets to 1, otherwise to 0
|
|
this.intersectionRatio = this.isIntersecting ? 1 : 0;
|
|
}
|
|
}
|
|
/**
|
|
* Creates the global IntersectionObserver constructor.
|
|
* https://w3c.github.io/IntersectionObserver/#intersection-observer-interface
|
|
* @param {Function} callback The function to be invoked after intersection
|
|
* changes have queued. The function is not invoked if the queue has
|
|
* been emptied by calling the `takeRecords` method.
|
|
* @param {Object=} opt_options Optional configuration options.
|
|
* @constructor
|
|
*/
|
|
|
|
|
|
function IntersectionObserver(callback, opt_options) {
|
|
var options = opt_options || {};
|
|
|
|
if (typeof callback != 'function') {
|
|
throw new Error('callback must be a function');
|
|
}
|
|
|
|
if (options.root && options.root.nodeType != 1) {
|
|
throw new Error('root must be an Element');
|
|
} // Binds and throttles `this._checkForIntersections`.
|
|
|
|
|
|
this._checkForIntersections = throttle(this._checkForIntersections.bind(this), this.THROTTLE_TIMEOUT); // Private properties.
|
|
|
|
this._callback = callback;
|
|
this._observationTargets = [];
|
|
this._queuedEntries = [];
|
|
this._rootMarginValues = this._parseRootMargin(options.rootMargin); // Public properties.
|
|
|
|
this.thresholds = this._initThresholds(options.threshold);
|
|
this.root = options.root || null;
|
|
this.rootMargin = this._rootMarginValues.map(_ref).join(' ');
|
|
/** @private @const {!Array<!Document>} */
|
|
|
|
this._monitoringDocuments = [];
|
|
/** @private @const {!Array<function()>} */
|
|
|
|
this._monitoringUnsubscribes = [];
|
|
}
|
|
/**
|
|
* The minimum interval within which the document will be checked for
|
|
* intersection changes.
|
|
*/
|
|
|
|
|
|
IntersectionObserver.prototype.THROTTLE_TIMEOUT = 100;
|
|
/**
|
|
* The frequency in which the polyfill polls for intersection changes.
|
|
* this can be updated on a per instance basis and must be set prior to
|
|
* calling `observe` on the first target.
|
|
*/
|
|
|
|
IntersectionObserver.prototype.POLL_INTERVAL = null;
|
|
/**
|
|
* Use a mutation observer on the root element
|
|
* to detect intersection changes.
|
|
*/
|
|
|
|
IntersectionObserver.prototype.USE_MUTATION_OBSERVER = true;
|
|
/**
|
|
* Sets up the polyfill in the cross-origin mode. The result is the
|
|
* updater function that accepts two arguments: `boundingClientRect` and
|
|
* `intersectionRect` - just as these fields would be available to the
|
|
* parent via `IntersectionObserverEntry`. This function should be called
|
|
* each time the iframe receives intersection information from the parent
|
|
* window, e.g. via messaging.
|
|
* @return {function(DOMRect|ClientRect, DOMRect|ClientRect)}
|
|
*/
|
|
|
|
function _crossOriginUpdater(boundingClientRect, intersectionRect) {
|
|
if (!boundingClientRect || !intersectionRect) {
|
|
crossOriginRect = getEmptyRect();
|
|
} else {
|
|
crossOriginRect = convertFromParentRect(boundingClientRect, intersectionRect);
|
|
}
|
|
|
|
registry.forEach(_ref2);
|
|
}
|
|
|
|
IntersectionObserver._setupCrossOriginUpdater = function () {
|
|
if (!crossOriginUpdater) {
|
|
/**
|
|
* @param {DOMRect|ClientRect} boundingClientRect
|
|
* @param {DOMRect|ClientRect} intersectionRect
|
|
*/
|
|
crossOriginUpdater = _crossOriginUpdater;
|
|
}
|
|
|
|
return crossOriginUpdater;
|
|
};
|
|
/**
|
|
* Resets the cross-origin mode.
|
|
*/
|
|
|
|
|
|
IntersectionObserver._resetCrossOriginUpdater = function () {
|
|
crossOriginUpdater = null;
|
|
crossOriginRect = null;
|
|
};
|
|
/**
|
|
* Starts observing a target element for intersection changes based on
|
|
* the thresholds values.
|
|
* @param {Element} target The DOM element to observe.
|
|
*/
|
|
|
|
|
|
IntersectionObserver.prototype.observe = _ref3;
|
|
/**
|
|
* Stops observing a target element for intersection changes.
|
|
* @param {Element} target The DOM element to observe.
|
|
*/
|
|
|
|
IntersectionObserver.prototype.unobserve = _ref4;
|
|
/**
|
|
* Stops observing all target elements for intersection changes.
|
|
*/
|
|
|
|
IntersectionObserver.prototype.disconnect = _ref5;
|
|
/**
|
|
* Returns any queue entries that have not yet been reported to the
|
|
* callback and clears the queue. This can be used in conjunction with the
|
|
* callback to obtain the absolute most up-to-date intersection information.
|
|
* @return {Array} The currently queued entries.
|
|
*/
|
|
|
|
IntersectionObserver.prototype.takeRecords = _ref6;
|
|
/**
|
|
* Accepts the threshold value from the user configuration object and
|
|
* returns a sorted array of unique threshold values. If a value is not
|
|
* between 0 and 1 and error is thrown.
|
|
* @private
|
|
* @param {Array|number=} opt_threshold An optional threshold value or
|
|
* a list of threshold values, defaulting to [0].
|
|
* @return {Array} A sorted list of unique and valid threshold values.
|
|
*/
|
|
|
|
IntersectionObserver.prototype._initThresholds = _ref8;
|
|
/**
|
|
* Accepts the rootMargin value from the user configuration object
|
|
* and returns an array of the four margin values as an object containing
|
|
* the value and unit properties. If any of the values are not properly
|
|
* formatted or use a unit other than px or %, and error is thrown.
|
|
* @private
|
|
* @param {string=} opt_rootMargin An optional rootMargin value,
|
|
* defaulting to '0px'.
|
|
* @return {Array<Object>} An array of margin objects with the keys
|
|
* value and unit.
|
|
*/
|
|
|
|
IntersectionObserver.prototype._parseRootMargin = _ref10;
|
|
/**
|
|
* Starts polling for intersection changes if the polling is not already
|
|
* happening, and if the page's visibility state is visible.
|
|
* @param {!Document} doc
|
|
* @private
|
|
*/
|
|
|
|
IntersectionObserver.prototype._monitorIntersections = function (doc) {
|
|
var win = doc.defaultView;
|
|
|
|
if (!win) {
|
|
// Already destroyed.
|
|
return;
|
|
}
|
|
|
|
if (this._monitoringDocuments.indexOf(doc) != -1) {
|
|
// Already monitoring.
|
|
return;
|
|
} // Private state for monitoring.
|
|
|
|
|
|
var callback = this._checkForIntersections;
|
|
var monitoringInterval = null;
|
|
var domObserver = null; // If a poll interval is set, use polling instead of listening to
|
|
// resize and scroll events or DOM mutations.
|
|
|
|
if (this.POLL_INTERVAL) {
|
|
monitoringInterval = win.setInterval(callback, this.POLL_INTERVAL);
|
|
} else {
|
|
addEvent(win, 'resize', callback, true);
|
|
addEvent(doc, 'scroll', callback, true);
|
|
|
|
if (this.USE_MUTATION_OBSERVER && 'MutationObserver' in win) {
|
|
domObserver = new win.MutationObserver(callback);
|
|
domObserver.observe(doc, {
|
|
attributes: true,
|
|
childList: true,
|
|
characterData: true,
|
|
subtree: true
|
|
});
|
|
}
|
|
}
|
|
|
|
this._monitoringDocuments.push(doc);
|
|
|
|
this._monitoringUnsubscribes.push(function () {
|
|
// Get the window object again. When a friendly iframe is destroyed, it
|
|
// will be null.
|
|
var win = doc.defaultView;
|
|
|
|
if (win) {
|
|
if (monitoringInterval) {
|
|
win.clearInterval(monitoringInterval);
|
|
}
|
|
|
|
removeEvent(win, 'resize', callback, true);
|
|
}
|
|
|
|
removeEvent(doc, 'scroll', callback, true);
|
|
|
|
if (domObserver) {
|
|
domObserver.disconnect();
|
|
}
|
|
}); // Also monitor the parent.
|
|
|
|
|
|
if (doc != (this.root && this.root.ownerDocument || document)) {
|
|
var frame = getFrameElement(doc);
|
|
|
|
if (frame) {
|
|
this._monitorIntersections(frame.ownerDocument);
|
|
}
|
|
}
|
|
};
|
|
/**
|
|
* Stops polling for intersection changes.
|
|
* @param {!Document} doc
|
|
* @private
|
|
*/
|
|
|
|
|
|
IntersectionObserver.prototype._unmonitorIntersections = function (doc) {
|
|
var index = this._monitoringDocuments.indexOf(doc);
|
|
|
|
if (index == -1) {
|
|
return;
|
|
}
|
|
|
|
var rootDoc = this.root && this.root.ownerDocument || document; // Check if any dependent targets are still remaining.
|
|
|
|
var hasDependentTargets = this._observationTargets.some(function (item) {
|
|
var itemDoc = item.element.ownerDocument; // Target is in this context.
|
|
|
|
if (itemDoc == doc) {
|
|
return true;
|
|
} // Target is nested in this context.
|
|
|
|
|
|
while (itemDoc && itemDoc != rootDoc) {
|
|
var frame = getFrameElement(itemDoc);
|
|
itemDoc = frame && frame.ownerDocument;
|
|
|
|
if (itemDoc == doc) {
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
});
|
|
|
|
if (hasDependentTargets) {
|
|
return;
|
|
} // Unsubscribe.
|
|
|
|
|
|
var unsubscribe = this._monitoringUnsubscribes[index];
|
|
|
|
this._monitoringDocuments.splice(index, 1);
|
|
|
|
this._monitoringUnsubscribes.splice(index, 1);
|
|
|
|
unsubscribe(); // Also unmonitor the parent.
|
|
|
|
if (doc != rootDoc) {
|
|
var frame = getFrameElement(doc);
|
|
|
|
if (frame) {
|
|
this._unmonitorIntersections(frame.ownerDocument);
|
|
}
|
|
}
|
|
};
|
|
/**
|
|
* Stops polling for intersection changes.
|
|
* @param {!Document} doc
|
|
* @private
|
|
*/
|
|
|
|
|
|
IntersectionObserver.prototype._unmonitorAllIntersections = _ref11;
|
|
/**
|
|
* Scans each observation target for intersection changes and adds them
|
|
* to the internal entries queue. If new entries are found, it
|
|
* schedules the callback to be invoked.
|
|
* @private
|
|
*/
|
|
|
|
IntersectionObserver.prototype._checkForIntersections = function () {
|
|
if (!this.root && crossOriginUpdater && !crossOriginRect) {
|
|
// Cross origin monitoring, but no initial data available yet.
|
|
return;
|
|
}
|
|
|
|
var rootIsInDom = this._rootIsInDom();
|
|
|
|
var rootRect = rootIsInDom ? this._getRootRect() : getEmptyRect();
|
|
|
|
this._observationTargets.forEach(function (item) {
|
|
var target = item.element;
|
|
var targetRect = getBoundingClientRect(target);
|
|
|
|
var rootContainsTarget = this._rootContainsTarget(target);
|
|
|
|
var oldEntry = item.entry;
|
|
|
|
var intersectionRect = rootIsInDom && rootContainsTarget && this._computeTargetAndRootIntersection(target, targetRect, rootRect);
|
|
|
|
var newEntry = item.entry = new IntersectionObserverEntry({
|
|
time: now(),
|
|
target: target,
|
|
boundingClientRect: targetRect,
|
|
rootBounds: crossOriginUpdater && !this.root ? null : rootRect,
|
|
intersectionRect: intersectionRect
|
|
});
|
|
|
|
if (!oldEntry) {
|
|
this._queuedEntries.push(newEntry);
|
|
} else if (rootIsInDom && rootContainsTarget) {
|
|
// If the new entry intersection ratio has crossed any of the
|
|
// thresholds, add a new entry.
|
|
if (this._hasCrossedThreshold(oldEntry, newEntry)) {
|
|
this._queuedEntries.push(newEntry);
|
|
}
|
|
} else {
|
|
// If the root is not in the DOM or target is not contained within
|
|
// root but the previous entry for this target had an intersection,
|
|
// add a new record indicating removal.
|
|
if (oldEntry && oldEntry.isIntersecting) {
|
|
this._queuedEntries.push(newEntry);
|
|
}
|
|
}
|
|
}, this);
|
|
|
|
if (this._queuedEntries.length) {
|
|
this._callback(this.takeRecords(), this);
|
|
}
|
|
};
|
|
/**
|
|
* Accepts a target and root rect computes the intersection between then
|
|
* following the algorithm in the spec.
|
|
* TODO(philipwalton): at this time clip-path is not considered.
|
|
* https://w3c.github.io/IntersectionObserver/#calculate-intersection-rect-algo
|
|
* @param {Element} target The target DOM element
|
|
* @param {Object} targetRect The bounding rect of the target.
|
|
* @param {Object} rootRect The bounding rect of the root after being
|
|
* expanded by the rootMargin value.
|
|
* @return {?Object} The final intersection rect object or undefined if no
|
|
* intersection is found.
|
|
* @private
|
|
*/
|
|
|
|
|
|
IntersectionObserver.prototype._computeTargetAndRootIntersection = function (target, targetRect, rootRect) {
|
|
// If the element isn't displayed, an intersection can't happen.
|
|
if (window.getComputedStyle(target).display == 'none') return;
|
|
var intersectionRect = targetRect;
|
|
var parent = getParentNode(target);
|
|
var atRoot = false;
|
|
|
|
while (!atRoot && parent) {
|
|
var parentRect = null;
|
|
var parentComputedStyle = parent.nodeType == 1 ? window.getComputedStyle(parent) : {}; // If the parent isn't displayed, an intersection can't happen.
|
|
|
|
if (parentComputedStyle.display == 'none') return null;
|
|
|
|
if (parent == this.root || parent.nodeType ==
|
|
/* DOCUMENT */
|
|
9) {
|
|
atRoot = true;
|
|
|
|
if (parent == this.root || parent == document) {
|
|
if (crossOriginUpdater && !this.root) {
|
|
if (!crossOriginRect || crossOriginRect.width == 0 && crossOriginRect.height == 0) {
|
|
// A 0-size cross-origin intersection means no-intersection.
|
|
parent = null;
|
|
parentRect = null;
|
|
intersectionRect = null;
|
|
} else {
|
|
parentRect = crossOriginRect;
|
|
}
|
|
} else {
|
|
parentRect = rootRect;
|
|
}
|
|
} else {
|
|
// Check if there's a frame that can be navigated to.
|
|
var frame = getParentNode(parent);
|
|
var frameRect = frame && getBoundingClientRect(frame);
|
|
|
|
var frameIntersect = frame && this._computeTargetAndRootIntersection(frame, frameRect, rootRect);
|
|
|
|
if (frameRect && frameIntersect) {
|
|
parent = frame;
|
|
parentRect = convertFromParentRect(frameRect, frameIntersect);
|
|
} else {
|
|
parent = null;
|
|
intersectionRect = null;
|
|
}
|
|
}
|
|
} else {
|
|
// If the element has a non-visible overflow, and it's not the <body>
|
|
// or <html> element, update the intersection rect.
|
|
// Note: <body> and <html> cannot be clipped to a rect that's not also
|
|
// the document rect, so no need to compute a new intersection.
|
|
var doc = parent.ownerDocument;
|
|
|
|
if (parent != doc.body && parent != doc.documentElement && parentComputedStyle.overflow != 'visible') {
|
|
parentRect = getBoundingClientRect(parent);
|
|
}
|
|
} // If either of the above conditionals set a new parentRect,
|
|
// calculate new intersection data.
|
|
|
|
|
|
if (parentRect) {
|
|
intersectionRect = computeRectIntersection(parentRect, intersectionRect);
|
|
}
|
|
|
|
if (!intersectionRect) break;
|
|
parent = parent && getParentNode(parent);
|
|
}
|
|
|
|
return intersectionRect;
|
|
};
|
|
/**
|
|
* Returns the root rect after being expanded by the rootMargin value.
|
|
* @return {ClientRect} The expanded root rect.
|
|
* @private
|
|
*/
|
|
|
|
|
|
IntersectionObserver.prototype._getRootRect = function () {
|
|
var rootRect;
|
|
|
|
if (this.root) {
|
|
rootRect = getBoundingClientRect(this.root);
|
|
} else {
|
|
// Use <html>/<body> instead of window since scroll bars affect size.
|
|
var html = document.documentElement;
|
|
var body = document.body;
|
|
rootRect = {
|
|
top: 0,
|
|
left: 0,
|
|
right: html.clientWidth || body.clientWidth,
|
|
width: html.clientWidth || body.clientWidth,
|
|
bottom: html.clientHeight || body.clientHeight,
|
|
height: html.clientHeight || body.clientHeight
|
|
};
|
|
}
|
|
|
|
return this._expandRectByRootMargin(rootRect);
|
|
};
|
|
/**
|
|
* Accepts a rect and expands it by the rootMargin value.
|
|
* @param {DOMRect|ClientRect} rect The rect object to expand.
|
|
* @return {ClientRect} The expanded rect.
|
|
* @private
|
|
*/
|
|
|
|
|
|
IntersectionObserver.prototype._expandRectByRootMargin = _ref12;
|
|
/**
|
|
* Accepts an old and new entry and returns true if at least one of the
|
|
* threshold values has been crossed.
|
|
* @param {?IntersectionObserverEntry} oldEntry The previous entry for a
|
|
* particular target element or null if no previous entry exists.
|
|
* @param {IntersectionObserverEntry} newEntry The current entry for a
|
|
* particular target element.
|
|
* @return {boolean} Returns true if a any threshold has been crossed.
|
|
* @private
|
|
*/
|
|
|
|
IntersectionObserver.prototype._hasCrossedThreshold = _ref13;
|
|
/**
|
|
* Returns whether or not the root element is an element and is in the DOM.
|
|
* @return {boolean} True if the root element is an element and is in the DOM.
|
|
* @private
|
|
*/
|
|
|
|
IntersectionObserver.prototype._rootIsInDom = function () {
|
|
return !this.root || containsDeep(document, this.root);
|
|
};
|
|
/**
|
|
* Returns whether or not the target element is a child of root.
|
|
* @param {Element} target The target element to check.
|
|
* @return {boolean} True if the target element is a child of root.
|
|
* @private
|
|
*/
|
|
|
|
|
|
IntersectionObserver.prototype._rootContainsTarget = function (target) {
|
|
return containsDeep(this.root || document, target) && (!this.root || this.root.ownerDocument == target.ownerDocument);
|
|
};
|
|
/**
|
|
* Adds the instance to the global IntersectionObserver registry if it isn't
|
|
* already present.
|
|
* @private
|
|
*/
|
|
|
|
|
|
IntersectionObserver.prototype._registerInstance = function () {
|
|
if (registry.indexOf(this) < 0) {
|
|
registry.push(this);
|
|
}
|
|
};
|
|
/**
|
|
* Removes the instance from the global IntersectionObserver registry.
|
|
* @private
|
|
*/
|
|
|
|
|
|
IntersectionObserver.prototype._unregisterInstance = function () {
|
|
var index = registry.indexOf(this);
|
|
if (index != -1) registry.splice(index, 1);
|
|
};
|
|
|
|
function getBoundingClientRect(el) {
|
|
var rect;
|
|
|
|
try {
|
|
rect = el.getBoundingClientRect();
|
|
} catch (err) {// Ignore Windows 7 IE11 "Unspecified error"
|
|
// https://github.com/w3c/IntersectionObserver/pull/205
|
|
}
|
|
|
|
if (!rect) return getEmptyRect(); // Older IE
|
|
|
|
if (!(rect.width && rect.height)) {
|
|
rect = {
|
|
top: rect.top,
|
|
right: rect.right,
|
|
bottom: rect.bottom,
|
|
left: rect.left,
|
|
width: rect.right - rect.left,
|
|
height: rect.bottom - rect.top
|
|
};
|
|
}
|
|
|
|
return rect;
|
|
}
|
|
|
|
function containsDeep(parent, child) {
|
|
var node = child;
|
|
|
|
while (node) {
|
|
if (node == parent) return true;
|
|
node = getParentNode(node);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
/**
|
|
* Gets the parent node of an element or its host element if the parent node
|
|
* is a shadow root.
|
|
* @param {Node} node The node whose parent to get.
|
|
* @return {Node|null} The parent node or null if no parent exists.
|
|
*/
|
|
|
|
|
|
function getParentNode(node) {
|
|
var parent = node.parentNode;
|
|
|
|
if (node.nodeType ==
|
|
/* DOCUMENT */
|
|
9 && node != document) {
|
|
// If this node is a document node, look for the embedding frame.
|
|
return getFrameElement(node);
|
|
}
|
|
|
|
if (parent && parent.nodeType == 11 && parent.host) {
|
|
// If the parent is a shadow root, return the host element.
|
|
return parent.host;
|
|
}
|
|
|
|
if (parent && parent.assignedSlot) {
|
|
// If the parent is distributed in a <slot>, return the parent of a slot.
|
|
return parent.assignedSlot.parentNode;
|
|
}
|
|
|
|
return parent;
|
|
}
|
|
|
|
window.IntersectionObserver = IntersectionObserver;
|
|
window.IntersectionObserverEntry = IntersectionObserverEntry;
|
|
})();
|
|
|
|
var usePassiveLayoutEffect = React[typeof document !== 'undefined' && document.createElement !== void 0 ? 'useLayoutEffect' : 'useEffect'];
|
|
|
|
function useIntersectionObserver(target, options) {
|
|
if (options === void 0) {
|
|
options = {};
|
|
}
|
|
|
|
var _options = options,
|
|
_options$root = _options.root,
|
|
root = _options$root === void 0 ? null : _options$root,
|
|
_options$pollInterval = _options.pollInterval,
|
|
pollInterval = _options$pollInterval === void 0 ? null : _options$pollInterval,
|
|
_options$useMutationO = _options.useMutationObserver,
|
|
useMutationObserver = _options$useMutationO === void 0 ? false : _options$useMutationO,
|
|
_options$rootMargin = _options.rootMargin,
|
|
rootMargin = _options$rootMargin === void 0 ? '0px 0px 0px 0px' : _options$rootMargin,
|
|
_options$threshold = _options.threshold,
|
|
threshold = _options$threshold === void 0 ? 0 : _options$threshold,
|
|
_options$initialIsInt = _options.initialIsIntersecting,
|
|
initialIsIntersecting = _options$initialIsInt === void 0 ? false : _options$initialIsInt;
|
|
|
|
var _React$useState = React.useState(function () {
|
|
return {
|
|
boundingClientRect: null,
|
|
intersectionRatio: 0,
|
|
intersectionRect: null,
|
|
isIntersecting: initialIsIntersecting,
|
|
rootBounds: null,
|
|
target: null,
|
|
time: 0
|
|
};
|
|
}),
|
|
entry = _React$useState[0],
|
|
setEntry = _React$useState[1];
|
|
|
|
var _React$useState2 = React.useState(function () {
|
|
return getIntersectionObserver({
|
|
root: root,
|
|
pollInterval: pollInterval,
|
|
useMutationObserver: useMutationObserver,
|
|
rootMargin: rootMargin,
|
|
threshold: threshold
|
|
});
|
|
}),
|
|
observer = _React$useState2[0],
|
|
setObserver = _React$useState2[1];
|
|
|
|
React.useEffect(function () {
|
|
var observer = getIntersectionObserver({
|
|
root: root,
|
|
pollInterval: pollInterval,
|
|
useMutationObserver: useMutationObserver,
|
|
rootMargin: rootMargin,
|
|
threshold: threshold
|
|
});
|
|
setObserver(observer); // eslint-disable-next-line react-hooks/exhaustive-deps
|
|
}, [root, rootMargin, pollInterval, useMutationObserver, JSON.stringify(threshold)]);
|
|
usePassiveLayoutEffect(function () {
|
|
var targetEl = target && 'current' in target ? target.current : target;
|
|
if (!observer || !targetEl) return;
|
|
var didUnsubscribe = false;
|
|
observer.observer.observe(targetEl);
|
|
|
|
var callback = function callback(entries) {
|
|
if (didUnsubscribe) return;
|
|
|
|
for (var i = 0; i < entries.length; i++) {
|
|
var _entry = entries[i];
|
|
|
|
if (_entry.target === targetEl) {
|
|
setEntry(_entry);
|
|
}
|
|
}
|
|
};
|
|
|
|
observer.subscribe(callback);
|
|
return function () {
|
|
didUnsubscribe = true;
|
|
observer.observer.unobserve(targetEl);
|
|
observer.unsubscribe(callback);
|
|
};
|
|
}, [target, observer]);
|
|
return entry;
|
|
}
|
|
|
|
function createIntersectionObserver(_ref) {
|
|
var _ref$root = _ref.root,
|
|
root = _ref$root === void 0 ? null : _ref$root,
|
|
_ref$pollInterval = _ref.pollInterval,
|
|
pollInterval = _ref$pollInterval === void 0 ? null : _ref$pollInterval,
|
|
_ref$useMutationObser = _ref.useMutationObserver,
|
|
useMutationObserver = _ref$useMutationObser === void 0 ? false : _ref$useMutationObser,
|
|
_ref$rootMargin = _ref.rootMargin,
|
|
rootMargin = _ref$rootMargin === void 0 ? '0px 0px 0px 0px' : _ref$rootMargin,
|
|
_ref$threshold = _ref.threshold,
|
|
threshold = _ref$threshold === void 0 ? 0 : _ref$threshold;
|
|
var callbacks = new Set();
|
|
if (typeof IntersectionObserver === 'undefined') return null;
|
|
var observer = new IntersectionObserver(function (entries) {
|
|
for (var _iterator = _createForOfIteratorHelperLoose(callbacks), _step; !(_step = _iterator()).done;) {
|
|
var callback = _step.value;
|
|
callback(entries, observer);
|
|
}
|
|
}, {
|
|
root: root,
|
|
rootMargin: rootMargin,
|
|
threshold: threshold
|
|
}); // @ts-ignore
|
|
|
|
observer.POLL_INTERVAL = pollInterval; // @ts-ignore
|
|
|
|
observer.USE_MUTATION_OBSERVER = useMutationObserver;
|
|
return {
|
|
observer: observer,
|
|
getListeners: function getListeners() {
|
|
return callbacks;
|
|
},
|
|
subscribe: function subscribe(callback) {
|
|
return callbacks.add(callback);
|
|
},
|
|
unsubscribe: function unsubscribe(callback) {
|
|
return callbacks.delete(callback);
|
|
}
|
|
};
|
|
}
|
|
|
|
var _intersectionObserver = /*#__PURE__*/new Map();
|
|
|
|
function getIntersectionObserver(options) {
|
|
var root = options.root,
|
|
keys = _objectWithoutPropertiesLoose(options, ["root"]);
|
|
|
|
var key = JSON.stringify(keys);
|
|
|
|
var base = _intersectionObserver.get(root);
|
|
|
|
if (!base) {
|
|
base = {};
|
|
|
|
_intersectionObserver.set(root, base);
|
|
}
|
|
|
|
return !base[key] ? base[key] = createIntersectionObserver(options) : base[key];
|
|
}
|
|
|
|
return useIntersectionObserver;
|
|
|
|
})));
|
|
//# sourceMappingURL=use-intersection-observer.dev.js.map
|