https://github.com/twbs/bootstrap
Tip revision: 8fa0d3010112dca5dd6dd501173415856001ba8b authored by XhmikosR on 13 February 2019, 16:01:40 UTC
Release v4.3.1. (#28252)
Release v4.3.1. (#28252)
Tip revision: 8fa0d30
scrollspy.js
/**
* --------------------------------------------------------------------------
* Bootstrap (v4.3.1): scrollspy.js
* Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
* --------------------------------------------------------------------------
*/
import $ from 'jquery'
import Util from './util'
/**
* ------------------------------------------------------------------------
* Constants
* ------------------------------------------------------------------------
*/
const NAME = 'scrollspy'
const VERSION = '4.3.1'
const DATA_KEY = 'bs.scrollspy'
const EVENT_KEY = `.${DATA_KEY}`
const DATA_API_KEY = '.data-api'
const JQUERY_NO_CONFLICT = $.fn[NAME]
const Default = {
offset : 10,
method : 'auto',
target : ''
}
const DefaultType = {
offset : 'number',
method : 'string',
target : '(string|element)'
}
const Event = {
ACTIVATE : `activate${EVENT_KEY}`,
SCROLL : `scroll${EVENT_KEY}`,
LOAD_DATA_API : `load${EVENT_KEY}${DATA_API_KEY}`
}
const ClassName = {
DROPDOWN_ITEM : 'dropdown-item',
DROPDOWN_MENU : 'dropdown-menu',
ACTIVE : 'active'
}
const Selector = {
DATA_SPY : '[data-spy="scroll"]',
ACTIVE : '.active',
NAV_LIST_GROUP : '.nav, .list-group',
NAV_LINKS : '.nav-link',
NAV_ITEMS : '.nav-item',
LIST_ITEMS : '.list-group-item',
DROPDOWN : '.dropdown',
DROPDOWN_ITEMS : '.dropdown-item',
DROPDOWN_TOGGLE : '.dropdown-toggle'
}
const OffsetMethod = {
OFFSET : 'offset',
POSITION : 'position'
}
/**
* ------------------------------------------------------------------------
* Class Definition
* ------------------------------------------------------------------------
*/
class ScrollSpy {
constructor(element, config) {
this._element = element
this._scrollElement = element.tagName === 'BODY' ? window : element
this._config = this._getConfig(config)
this._selector = `${this._config.target} ${Selector.NAV_LINKS},` +
`${this._config.target} ${Selector.LIST_ITEMS},` +
`${this._config.target} ${Selector.DROPDOWN_ITEMS}`
this._offsets = []
this._targets = []
this._activeTarget = null
this._scrollHeight = 0
$(this._scrollElement).on(Event.SCROLL, (event) => this._process(event))
this.refresh()
this._process()
}
// Getters
static get VERSION() {
return VERSION
}
static get Default() {
return Default
}
// Public
refresh() {
const autoMethod = this._scrollElement === this._scrollElement.window
? OffsetMethod.OFFSET : OffsetMethod.POSITION
const offsetMethod = this._config.method === 'auto'
? autoMethod : this._config.method
const offsetBase = offsetMethod === OffsetMethod.POSITION
? this._getScrollTop() : 0
this._offsets = []
this._targets = []
this._scrollHeight = this._getScrollHeight()
const targets = [].slice.call(document.querySelectorAll(this._selector))
targets
.map((element) => {
let target
const targetSelector = Util.getSelectorFromElement(element)
if (targetSelector) {
target = document.querySelector(targetSelector)
}
if (target) {
const targetBCR = target.getBoundingClientRect()
if (targetBCR.width || targetBCR.height) {
// TODO (fat): remove sketch reliance on jQuery position/offset
return [
$(target)[offsetMethod]().top + offsetBase,
targetSelector
]
}
}
return null
})
.filter((item) => item)
.sort((a, b) => a[0] - b[0])
.forEach((item) => {
this._offsets.push(item[0])
this._targets.push(item[1])
})
}
dispose() {
$.removeData(this._element, DATA_KEY)
$(this._scrollElement).off(EVENT_KEY)
this._element = null
this._scrollElement = null
this._config = null
this._selector = null
this._offsets = null
this._targets = null
this._activeTarget = null
this._scrollHeight = null
}
// Private
_getConfig(config) {
config = {
...Default,
...typeof config === 'object' && config ? config : {}
}
if (typeof config.target !== 'string') {
let id = $(config.target).attr('id')
if (!id) {
id = Util.getUID(NAME)
$(config.target).attr('id', id)
}
config.target = `#${id}`
}
Util.typeCheckConfig(NAME, config, DefaultType)
return config
}
_getScrollTop() {
return this._scrollElement === window
? this._scrollElement.pageYOffset : this._scrollElement.scrollTop
}
_getScrollHeight() {
return this._scrollElement.scrollHeight || Math.max(
document.body.scrollHeight,
document.documentElement.scrollHeight
)
}
_getOffsetHeight() {
return this._scrollElement === window
? window.innerHeight : this._scrollElement.getBoundingClientRect().height
}
_process() {
const scrollTop = this._getScrollTop() + this._config.offset
const scrollHeight = this._getScrollHeight()
const maxScroll = this._config.offset +
scrollHeight -
this._getOffsetHeight()
if (this._scrollHeight !== scrollHeight) {
this.refresh()
}
if (scrollTop >= maxScroll) {
const target = this._targets[this._targets.length - 1]
if (this._activeTarget !== target) {
this._activate(target)
}
return
}
if (this._activeTarget && scrollTop < this._offsets[0] && this._offsets[0] > 0) {
this._activeTarget = null
this._clear()
return
}
const offsetLength = this._offsets.length
for (let i = offsetLength; i--;) {
const isActiveTarget = this._activeTarget !== this._targets[i] &&
scrollTop >= this._offsets[i] &&
(typeof this._offsets[i + 1] === 'undefined' ||
scrollTop < this._offsets[i + 1])
if (isActiveTarget) {
this._activate(this._targets[i])
}
}
}
_activate(target) {
this._activeTarget = target
this._clear()
const queries = this._selector
.split(',')
.map((selector) => `${selector}[data-target="${target}"],${selector}[href="${target}"]`)
const $link = $([].slice.call(document.querySelectorAll(queries.join(','))))
if ($link.hasClass(ClassName.DROPDOWN_ITEM)) {
$link.closest(Selector.DROPDOWN).find(Selector.DROPDOWN_TOGGLE).addClass(ClassName.ACTIVE)
$link.addClass(ClassName.ACTIVE)
} else {
// Set triggered link as active
$link.addClass(ClassName.ACTIVE)
// Set triggered links parents as active
// With both <ul> and <nav> markup a parent is the previous sibling of any nav ancestor
$link.parents(Selector.NAV_LIST_GROUP).prev(`${Selector.NAV_LINKS}, ${Selector.LIST_ITEMS}`).addClass(ClassName.ACTIVE)
// Handle special case when .nav-link is inside .nav-item
$link.parents(Selector.NAV_LIST_GROUP).prev(Selector.NAV_ITEMS).children(Selector.NAV_LINKS).addClass(ClassName.ACTIVE)
}
$(this._scrollElement).trigger(Event.ACTIVATE, {
relatedTarget: target
})
}
_clear() {
[].slice.call(document.querySelectorAll(this._selector))
.filter((node) => node.classList.contains(ClassName.ACTIVE))
.forEach((node) => node.classList.remove(ClassName.ACTIVE))
}
// Static
static _jQueryInterface(config) {
return this.each(function () {
let data = $(this).data(DATA_KEY)
const _config = typeof config === 'object' && config
if (!data) {
data = new ScrollSpy(this, _config)
$(this).data(DATA_KEY, data)
}
if (typeof config === 'string') {
if (typeof data[config] === 'undefined') {
throw new TypeError(`No method named "${config}"`)
}
data[config]()
}
})
}
}
/**
* ------------------------------------------------------------------------
* Data Api implementation
* ------------------------------------------------------------------------
*/
$(window).on(Event.LOAD_DATA_API, () => {
const scrollSpys = [].slice.call(document.querySelectorAll(Selector.DATA_SPY))
const scrollSpysLength = scrollSpys.length
for (let i = scrollSpysLength; i--;) {
const $spy = $(scrollSpys[i])
ScrollSpy._jQueryInterface.call($spy, $spy.data())
}
})
/**
* ------------------------------------------------------------------------
* jQuery
* ------------------------------------------------------------------------
*/
$.fn[NAME] = ScrollSpy._jQueryInterface
$.fn[NAME].Constructor = ScrollSpy
$.fn[NAME].noConflict = () => {
$.fn[NAME] = JQUERY_NO_CONFLICT
return ScrollSpy._jQueryInterface
}
export default ScrollSpy