/*! * smooth-scroll v16.1.2 * Animate scrolling to anchor links * (c) 2020 Chris Ferdinandi * MIT License * http://github.com/cferdinandi/smooth-scroll */ /** * closest() polyfill * @link https://developer.mozilla.org/en-US/docs/Web/API/Element/closest#Polyfill */ if (window.Element && !Element.prototype.closest) { Element.prototype.closest = function(s) { var matches = (this.document || this.ownerDocument).querySelectorAll(s), i, el = this; do { i = matches.length; while (--i >= 0 && matches.item(i) !== el) {} } while ((i < 0) && (el = el.parentElement)); return el; }; } /** * CustomEvent() polyfill * https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent#Polyfill */ (function () { if (typeof window.CustomEvent === "function") return false; function CustomEvent(event, params) { params = params || { bubbles: false, cancelable: false, detail: undefined }; var evt = document.createEvent('CustomEvent'); evt.initCustomEvent(event, params.bubbles, params.cancelable, params.detail); return evt; } CustomEvent.prototype = window.Event.prototype; window.CustomEvent = CustomEvent; })(); /** * requestAnimationFrame() polyfill * By Erik Möller. Fixes from Paul Irish and Tino Zijdel. * @link http://paulirish.com/2011/requestanimationframe-for-smart-animating/ * @link http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating * @license MIT */ (function() { var lastTime = 0; var vendors = ['ms', 'moz', 'webkit', 'o']; for(var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) { window.requestAnimationFrame = window[vendors[x]+'RequestAnimationFrame']; window.cancelAnimationFrame = window[vendors[x]+'CancelAnimationFrame'] || window[vendors[x]+'CancelRequestAnimationFrame']; } if (!window.requestAnimationFrame) { window.requestAnimationFrame = function(callback, element) { var currTime = new Date().getTime(); var timeToCall = Math.max(0, 16 - (currTime - lastTime)); var id = window.setTimeout((function() { callback(currTime + timeToCall); }), timeToCall); lastTime = currTime + timeToCall; return id; }; } if (!window.cancelAnimationFrame) { window.cancelAnimationFrame = function(id) { clearTimeout(id); }; } }()); (function (root, factory) { if (typeof define === 'function' && define.amd) { define([], (function () { return factory(root); })); } else if (typeof exports === 'object') { module.exports = factory(root); } else { root.SmoothScroll = factory(root); } })(typeof global !== 'undefined' ? global : typeof window !== 'undefined' ? window : this, (function (window) { 'use strict'; // // Default settings // var defaults = { // Selectors ignore: '[data-scroll-ignore]', header: null, topOnEmptyHash: true, // Speed & Duration speed: 500, speedAsDuration: false, durationMax: null, durationMin: null, clip: true, offset: 0, // Easing easing: 'easeInOutCubic', customEasing: null, // History updateURL: true, popstate: true, // Custom Events emitEvents: true }; // // Utility Methods // /** * Check if browser supports required methods * @return {Boolean} Returns true if all required methods are supported */ var supports = function () { return ( 'querySelector' in document && 'addEventListener' in window && 'requestAnimationFrame' in window && 'closest' in window.Element.prototype ); }; /** * Merge two or more objects together. * @param {Object} objects The objects to merge together * @returns {Object} Merged values of defaults and options */ var extend = function () { var merged = {}; Array.prototype.forEach.call(arguments, (function (obj) { for (var key in obj) { if (!obj.hasOwnProperty(key)) return; merged[key] = obj[key]; } })); return merged; }; /** * Check to see if user prefers reduced motion * @param {Object} settings Script settings */ var reduceMotion = function () { if ('matchMedia' in window && window.matchMedia('(prefers-reduced-motion)').matches) { return true; } return false; }; /** * Get the height of an element. * @param {Node} elem The element to get the height of * @return {Number} The element's height in pixels */ var getHeight = function (elem) { return parseInt(window.getComputedStyle(elem).height, 10); }; /** * Escape special characters for use with querySelector * @author Mathias Bynens * @link https://github.com/mathiasbynens/CSS.escape * @param {String} id The anchor ID to escape */ var escapeCharacters = function (id) { // Remove leading hash if (id.charAt(0) === '#') { id = id.substr(1); } var string = String(id); var length = string.length; var index = -1; var codeUnit; var result = ''; var firstCodeUnit = string.charCodeAt(0); while (++index < length) { codeUnit = string.charCodeAt(index); // Note: there’s no need to special-case astral symbols, surrogate // pairs, or lone surrogates. // If the character is NULL (U+0000), then throw an // `InvalidCharacterError` exception and terminate these steps. if (codeUnit === 0x0000) { throw new InvalidCharacterError( 'Invalid character: the input contains U+0000.' ); } if ( // If the character is in the range [\1-\1F] (U+0001 to U+001F) or is // U+007F, […] (codeUnit >= 0x0001 && codeUnit <= 0x001F) || codeUnit == 0x007F || // If the character is the first character and is in the range [0-9] // (U+0030 to U+0039), […] (index === 0 && codeUnit >= 0x0030 && codeUnit <= 0x0039) || // If the character is the second character and is in the range [0-9] // (U+0030 to U+0039) and the first character is a `-` (U+002D), […] ( index === 1 && codeUnit >= 0x0030 && codeUnit <= 0x0039 && firstCodeUnit === 0x002D ) ) { // http://dev.w3.org/csswg/cssom/#escape-a-character-as-code-point result += '\\' + codeUnit.toString(16) + ' '; continue; } // If the character is not handled by one of the above rules and is // greater than or equal to U+0080, is `-` (U+002D) or `_` (U+005F), or // is in one of the ranges [0-9] (U+0030 to U+0039), [A-Z] (U+0041 to // U+005A), or [a-z] (U+0061 to U+007A), […] if ( codeUnit >= 0x0080 || codeUnit === 0x002D || codeUnit === 0x005F || codeUnit >= 0x0030 && codeUnit <= 0x0039 || codeUnit >= 0x0041 && codeUnit <= 0x005A || codeUnit >= 0x0061 && codeUnit <= 0x007A ) { // the character itself result += string.charAt(index); continue; } // Otherwise, the escaped character. // http://dev.w3.org/csswg/cssom/#escape-a-character result += '\\' + string.charAt(index); } // Return sanitized hash return '#' + result; }; /** * Calculate the easing pattern * @link https://gist.github.com/gre/1650294 * @param {String} type Easing pattern * @param {Number} time Time animation should take to complete * @returns {Number} */ var easingPattern = function (settings, time) { var pattern; // Default Easing Patterns if (settings.easing === 'easeInQuad') pattern = time * time; // accelerating from zero velocity if (settings.easing === 'easeOutQuad') pattern = time * (2 - time); // decelerating to zero velocity if (settings.easing === 'easeInOutQuad') pattern = time < 0.5 ? 2 * time * time : -1 + (4 - 2 * time) * time; // acceleration until halfway, then deceleration if (settings.easing === 'easeInCubic') pattern = time * time * time; // accelerating from zero velocity if (settings.easing === 'easeOutCubic') pattern = (--time) * time * time + 1; // decelerating to zero velocity if (settings.easing === 'easeInOutCubic') pattern = time < 0.5 ? 4 * time * time * time : (time - 1) * (2 * time - 2) * (2 * time - 2) + 1; // acceleration until halfway, then deceleration if (settings.easing === 'easeInQuart') pattern = time * time * time * time; // accelerating from zero velocity if (settings.easing === 'easeOutQuart') pattern = 1 - (--time) * time * time * time; // decelerating to zero velocity if (settings.easing === 'easeInOutQuart') pattern = time < 0.5 ? 8 * time * time * time * time : 1 - 8 * (--time) * time * time * time; // acceleration until halfway, then deceleration if (settings.easing === 'easeInQuint') pattern = time * time * time * time * time; // accelerating from zero velocity if (settings.easing === 'easeOutQuint') pattern = 1 + (--time) * time * time * time * time; // decelerating to zero velocity if (settings.easing === 'easeInOutQuint') pattern = time < 0.5 ? 16 * time * time * time * time * time : 1 + 16 * (--time) * time * time * time * time; // acceleration until halfway, then deceleration // Custom Easing Patterns if (!!settings.customEasing) pattern = settings.customEasing(time); return pattern || time; // no easing, no acceleration }; /** * Determine the document's height * @returns {Number} */ var getDocumentHeight = function () { return Math.max( document.body.scrollHeight, document.documentElement.scrollHeight, document.body.offsetHeight, document.documentElement.offsetHeight, document.body.clientHeight, document.documentElement.clientHeight ); }; /** * Calculate how far to scroll * Clip support added by robjtede - https://github.com/cferdinandi/smooth-scroll/issues/405 * @param {Element} anchor The anchor element to scroll to * @param {Number} headerHeight Height of a fixed header, if any * @param {Number} offset Number of pixels by which to offset scroll * @param {Boolean} clip If true, adjust scroll distance to prevent abrupt stops near the bottom of the page * @returns {Number} */ var getEndLocation = function (anchor, headerHeight, offset, clip) { var location = 0; if (anchor.offsetParent) { do { location += anchor.offsetTop; anchor = anchor.offsetParent; } while (anchor); } location = Math.max(location - headerHeight - offset, 0); if (clip) { location = Math.min(location, getDocumentHeight() - window.innerHeight); } return location; }; /** * Get the height of the fixed header * @param {Node} header The header * @return {Number} The height of the header */ var getHeaderHeight = function (header) { return !header ? 0 : (getHeight(header) + header.offsetTop); }; /** * Calculate the speed to use for the animation * @param {Number} distance The distance to travel * @param {Object} settings The plugin settings * @return {Number} How fast to animate */ var getSpeed = function (distance, settings) { var speed = settings.speedAsDuration ? settings.speed : Math.abs(distance / 1000 * settings.speed); if (settings.durationMax && speed > settings.durationMax) return settings.durationMax; if (settings.durationMin && speed < settings.durationMin) return settings.durationMin; return parseInt(speed, 10); }; var setHistory = function (options) { // Make sure this should run if (!history.replaceState || !options.updateURL || history.state) return; // Get the hash to use var hash = window.location.hash; hash = hash ? hash : ''; // Set a default history history.replaceState( { smoothScroll: JSON.stringify(options), anchor: hash ? hash : window.pageYOffset }, document.title, hash ? hash : window.location.href ); }; /** * Update the URL * @param {Node} anchor The anchor that was scrolled to * @param {Boolean} isNum If true, anchor is a number * @param {Object} options Settings for Smooth Scroll */ var updateURL = function (anchor, isNum, options) { // Bail if the anchor is a number if (isNum) return; // Verify that pushState is supported and the updateURL option is enabled if (!history.pushState || !options.updateURL) return; // Update URL history.pushState( { smoothScroll: JSON.stringify(options), anchor: anchor.id }, document.title, anchor === document.documentElement ? '#top' : '#' + anchor.id ); }; /** * Bring the anchored element into focus * @param {Node} anchor The anchor element * @param {Number} endLocation The end location to scroll to * @param {Boolean} isNum If true, scroll is to a position rather than an element */ var adjustFocus = function (anchor, endLocation, isNum) { // Is scrolling to top of page, blur if (anchor === 0) { document.body.focus(); } // Don't run if scrolling to a number on the page if (isNum) return; // Otherwise, bring anchor element into focus anchor.focus(); if (document.activeElement !== anchor) { anchor.setAttribute('tabindex', '-1'); anchor.focus(); anchor.style.outline = 'none'; } window.scrollTo(0 , endLocation); }; /** * Emit a custom event * @param {String} type The event type * @param {Object} options The settings object * @param {Node} anchor The anchor element * @param {Node} toggle The toggle element */ var emitEvent = function (type, options, anchor, toggle) { if (!options.emitEvents || typeof window.CustomEvent !== 'function') return; var event = new CustomEvent(type, { bubbles: true, detail: { anchor: anchor, toggle: toggle } }); document.dispatchEvent(event); }; // // SmoothScroll Constructor // var SmoothScroll = function (selector, options) { // // Variables // var smoothScroll = {}; // Object for public APIs var settings, anchor, toggle, fixedHeader, eventTimeout, animationInterval; // // Methods // /** * Cancel a scroll-in-progress */ smoothScroll.cancelScroll = function (noEvent) { cancelAnimationFrame(animationInterval); animationInterval = null; if (noEvent) return; emitEvent('scrollCancel', settings); }; /** * Start/stop the scrolling animation * @param {Node|Number} anchor The element or position to scroll to * @param {Element} toggle The element that toggled the scroll event * @param {Object} options */ smoothScroll.animateScroll = function (anchor, toggle, options) { // Cancel any in progress scrolls smoothScroll.cancelScroll(); // Local settings var _settings = extend(settings || defaults, options || {}); // Merge user options with defaults // Selectors and variables var isNum = Object.prototype.toString.call(anchor) === '[object Number]' ? true : false; var anchorElem = isNum || !anchor.tagName ? null : anchor; if (!isNum && !anchorElem) return; var startLocation = window.pageYOffset; // Current location on the page if (_settings.header && !fixedHeader) { // Get the fixed header if not already set fixedHeader = document.querySelector(_settings.header); } var headerHeight = getHeaderHeight(fixedHeader); var endLocation = isNum ? anchor : getEndLocation(anchorElem, headerHeight, parseInt((typeof _settings.offset === 'function' ? _settings.offset(anchor, toggle) : _settings.offset), 10), _settings.clip); // Location to scroll to var distance = endLocation - startLocation; // distance to travel var documentHeight = getDocumentHeight(); var timeLapsed = 0; var speed = getSpeed(distance, _settings); var start, percentage, position; /** * Stop the scroll animation when it reaches its target (or the bottom/top of page) * @param {Number} position Current position on the page * @param {Number} endLocation Scroll to location * @param {Number} animationInterval How much to scroll on this loop */ var stopAnimateScroll = function (position, endLocation) { // Get the current location var currentLocation = window.pageYOffset; // Check if the end location has been reached yet (or we've hit the end of the document) if (position == endLocation || currentLocation == endLocation || ((startLocation < endLocation && window.innerHeight + currentLocation) >= documentHeight)) { // Clear the animation timer smoothScroll.cancelScroll(true); // Bring the anchored element into focus adjustFocus(anchor, endLocation, isNum); // Emit a custom event emitEvent('scrollStop', _settings, anchor, toggle); // Reset start start = null; animationInterval = null; return true; } }; /** * Loop scrolling animation */ var loopAnimateScroll = function (timestamp) { if (!start) { start = timestamp; } timeLapsed += timestamp - start; percentage = speed === 0 ? 0 : (timeLapsed / speed); percentage = (percentage > 1) ? 1 : percentage; position = startLocation + (distance * easingPattern(_settings, percentage)); window.scrollTo(0, Math.floor(position)); if (!stopAnimateScroll(position, endLocation)) { animationInterval = window.requestAnimationFrame(loopAnimateScroll); start = timestamp; } }; /** * Reset position to fix weird iOS bug * @link https://github.com/cferdinandi/smooth-scroll/issues/45 */ if (window.pageYOffset === 0) { window.scrollTo(0, 0); } // Update the URL updateURL(anchor, isNum, _settings); // If the user prefers reduced motion, jump to location if (reduceMotion()) { window.scrollTo(0, Math.floor(endLocation)); return; } // Emit a custom event emitEvent('scrollStart', _settings, anchor, toggle); // Start scrolling animation smoothScroll.cancelScroll(true); window.requestAnimationFrame(loopAnimateScroll); }; /** * If smooth scroll element clicked, animate scroll */ var clickHandler = function (event) { // Don't run if event was canceled but still bubbled up // By @mgreter - https://github.com/cferdinandi/smooth-scroll/pull/462/ if (event.defaultPrevented) return; // Don't run if right-click or command/control + click or shift + click if (event.button !== 0 || event.metaKey || event.ctrlKey || event.shiftKey) return; // Check if event.target has closest() method // By @totegi - https://github.com/cferdinandi/smooth-scroll/pull/401/ if (!('closest' in event.target)) return; // Check if a smooth scroll link was clicked toggle = event.target.closest(selector); if (!toggle || toggle.tagName.toLowerCase() !== 'a' || event.target.closest(settings.ignore)) return; // Only run if link is an anchor and points to the current page if (toggle.hostname !== window.location.hostname || toggle.pathname !== window.location.pathname || !/#/.test(toggle.href)) return; // Get an escaped version of the hash var hash; try { hash = escapeCharacters(decodeURIComponent(toggle.hash)); } catch(e) { hash = escapeCharacters(toggle.hash); } // Get the anchored element var anchor; if (hash === '#') { if (!settings.topOnEmptyHash) return; anchor = document.documentElement; } else { anchor = document.querySelector(hash); } anchor = !anchor && hash === '#top' ? document.documentElement : anchor; // If anchored element exists, scroll to it if (!anchor) return; event.preventDefault(); setHistory(settings); smoothScroll.animateScroll(anchor, toggle); }; /** * Animate scroll on popstate events */ var popstateHandler = function (event) { // Stop if history.state doesn't exist (ex. if clicking on a broken anchor link). // fixes `Cannot read property 'smoothScroll' of null` error getting thrown. if (history.state === null) return; // Only run if state is a popstate record for this instantiation if (!history.state.smoothScroll || history.state.smoothScroll !== JSON.stringify(settings)) return; // Only run if state includes an anchor // if (!history.state.anchor && history.state.anchor !== 0) return; // Get the anchor var anchor = history.state.anchor; if (typeof anchor === 'string' && anchor) { anchor = document.querySelector(escapeCharacters(history.state.anchor)); if (!anchor) return; } // Animate scroll to anchor link smoothScroll.animateScroll(anchor, null, {updateURL: false}); }; /** * Destroy the current initialization. */ smoothScroll.destroy = function () { // If plugin isn't already initialized, stop if (!settings) return; // Remove event listeners document.removeEventListener('click', clickHandler, false); window.removeEventListener('popstate', popstateHandler, false); // Cancel any scrolls-in-progress smoothScroll.cancelScroll(); // Reset variables settings = null; anchor = null; toggle = null; fixedHeader = null; eventTimeout = null; animationInterval = null; }; /** * Initialize Smooth Scroll * @param {Object} options User settings */ var init = function () { // feature test if (!supports()) throw 'Smooth Scroll: This browser does not support the required JavaScript methods and browser APIs.'; // Destroy any existing initializations smoothScroll.destroy(); // Selectors and variables settings = extend(defaults, options || {}); // Merge user options with defaults fixedHeader = settings.header ? document.querySelector(settings.header) : null; // Get the fixed header // When a toggle is clicked, run the click handler document.addEventListener('click', clickHandler, false); // If updateURL and popState are enabled, listen for pop events if (settings.updateURL && settings.popstate) { window.addEventListener('popstate', popstateHandler, false); } }; // // Initialize plugin // init(); // // Public APIs // return smoothScroll; }; return SmoothScroll; }));