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Bootstrap/js/src/carousel.js

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/**
* --------------------------------------------------------------------------
* Bootstrap (v4.3.0): carousel.js
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* Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
* --------------------------------------------------------------------------
*/
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import $ from 'jquery'
import Util from './util'
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/**
* ------------------------------------------------------------------------
* Constants
* ------------------------------------------------------------------------
*/
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const NAME = 'carousel'
const VERSION = '4.3.0'
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const DATA_KEY = 'bs.carousel'
const EVENT_KEY = `.${DATA_KEY}`
const DATA_API_KEY = '.data-api'
const JQUERY_NO_CONFLICT = $.fn[NAME]
const ARROW_LEFT_KEYCODE = 37 // KeyboardEvent.which value for left arrow key
const ARROW_RIGHT_KEYCODE = 39 // KeyboardEvent.which value for right arrow key
const TOUCHEVENT_COMPAT_WAIT = 500 // Time for mouse compat events to fire after touch
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const SWIPE_THRESHOLD = 40
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const Default = {
interval : 5000,
keyboard : true,
slide : false,
pause : 'hover',
wrap : true,
touch : true
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}
const DefaultType = {
interval : '(number|boolean)',
keyboard : 'boolean',
slide : '(boolean|string)',
pause : '(string|boolean)',
wrap : 'boolean',
touch : 'boolean'
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}
const Direction = {
NEXT : 'next',
PREV : 'prev',
LEFT : 'left',
RIGHT : 'right'
}
const Event = {
SLIDE : `slide${EVENT_KEY}`,
SLID : `slid${EVENT_KEY}`,
KEYDOWN : `keydown${EVENT_KEY}`,
MOUSEENTER : `mouseenter${EVENT_KEY}`,
MOUSELEAVE : `mouseleave${EVENT_KEY}`,
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TOUCHSTART : `touchstart${EVENT_KEY}`,
TOUCHMOVE : `touchmove${EVENT_KEY}`,
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TOUCHEND : `touchend${EVENT_KEY}`,
POINTERDOWN : `pointerdown${EVENT_KEY}`,
POINTERUP : `pointerup${EVENT_KEY}`,
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DRAG_START : `dragstart${EVENT_KEY}`,
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LOAD_DATA_API : `load${EVENT_KEY}${DATA_API_KEY}`,
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CLICK_DATA_API : `click${EVENT_KEY}${DATA_API_KEY}`
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}
const ClassName = {
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CAROUSEL : 'carousel',
ACTIVE : 'active',
SLIDE : 'slide',
RIGHT : 'carousel-item-right',
LEFT : 'carousel-item-left',
NEXT : 'carousel-item-next',
PREV : 'carousel-item-prev',
ITEM : 'carousel-item',
POINTER_EVENT : 'pointer-event'
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}
const Selector = {
ACTIVE : '.active',
ACTIVE_ITEM : '.active.carousel-item',
ITEM : '.carousel-item',
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ITEM_IMG : '.carousel-item img',
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NEXT_PREV : '.carousel-item-next, .carousel-item-prev',
INDICATORS : '.carousel-indicators',
DATA_SLIDE : '[data-slide], [data-slide-to]',
DATA_RIDE : '[data-ride="carousel"]'
}
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const PointerType = {
TOUCH : 'touch',
PEN : 'pen'
}
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/**
* ------------------------------------------------------------------------
* Class Definition
* ------------------------------------------------------------------------
*/
class Carousel {
constructor(element, config) {
this._items = null
this._interval = null
this._activeElement = null
this._isPaused = false
this._isSliding = false
this.touchTimeout = null
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this.touchStartX = 0
this.touchDeltaX = 0
this._config = this._getConfig(config)
this._element = element
this._indicatorsElement = this._element.querySelector(Selector.INDICATORS)
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this._touchSupported = 'ontouchstart' in document.documentElement || navigator.maxTouchPoints > 0
this._pointerEvent = Boolean(window.PointerEvent || window.MSPointerEvent)
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this._addEventListeners()
}
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// Getters
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static get VERSION() {
return VERSION
}
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static get Default() {
return Default
}
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// Public
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next() {
if (!this._isSliding) {
this._slide(Direction.NEXT)
}
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}
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nextWhenVisible() {
// Don't call next when the page isn't visible
// or the carousel or its parent isn't visible
if (!document.hidden &&
($(this._element).is(':visible') && $(this._element).css('visibility') !== 'hidden')) {
this.next()
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}
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}
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prev() {
if (!this._isSliding) {
this._slide(Direction.PREV)
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}
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}
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pause(event) {
if (!event) {
this._isPaused = true
}
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if (this._element.querySelector(Selector.NEXT_PREV)) {
Util.triggerTransitionEnd(this._element)
this.cycle(true)
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}
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clearInterval(this._interval)
this._interval = null
}
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cycle(event) {
if (!event) {
this._isPaused = false
}
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if (this._interval) {
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clearInterval(this._interval)
this._interval = null
}
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if (this._config.interval && !this._isPaused) {
this._interval = setInterval(
(document.visibilityState ? this.nextWhenVisible : this.next).bind(this),
this._config.interval
)
}
}
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to(index) {
this._activeElement = this._element.querySelector(Selector.ACTIVE_ITEM)
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const activeIndex = this._getItemIndex(this._activeElement)
if (index > this._items.length - 1 || index < 0) {
return
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}
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if (this._isSliding) {
$(this._element).one(Event.SLID, () => this.to(index))
return
}
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if (activeIndex === index) {
this.pause()
this.cycle()
return
}
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const direction = index > activeIndex
? Direction.NEXT
: Direction.PREV
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this._slide(direction, this._items[index])
}
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dispose() {
$(this._element).off(EVENT_KEY)
$.removeData(this._element, DATA_KEY)
this._items = null
this._config = null
this._element = null
this._interval = null
this._isPaused = null
this._isSliding = null
this._activeElement = null
this._indicatorsElement = null
}
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// Private
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_getConfig(config) {
config = {
...Default,
...config
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}
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Util.typeCheckConfig(NAME, config, DefaultType)
return config
}
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_handleSwipe() {
const absDeltax = Math.abs(this.touchDeltaX)
if (absDeltax <= SWIPE_THRESHOLD) {
return
}
const direction = absDeltax / this.touchDeltaX
// swipe left
if (direction > 0) {
this.prev()
}
// swipe right
if (direction < 0) {
this.next()
}
}
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_addEventListeners() {
if (this._config.keyboard) {
$(this._element)
.on(Event.KEYDOWN, (event) => this._keydown(event))
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}
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if (this._config.pause === 'hover') {
$(this._element)
.on(Event.MOUSEENTER, (event) => this.pause(event))
.on(Event.MOUSELEAVE, (event) => this.cycle(event))
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}
if (this._config.touch) {
this._addTouchEventListeners()
}
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}
_addTouchEventListeners() {
if (!this._touchSupported) {
return
}
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const start = (event) => {
if (this._pointerEvent && PointerType[event.originalEvent.pointerType.toUpperCase()]) {
this.touchStartX = event.originalEvent.clientX
} else if (!this._pointerEvent) {
this.touchStartX = event.originalEvent.touches[0].clientX
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}
}
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const move = (event) => {
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// ensure swiping with one touch and not pinching
if (event.originalEvent.touches && event.originalEvent.touches.length > 1) {
this.touchDeltaX = 0
} else {
this.touchDeltaX = event.originalEvent.touches[0].clientX - this.touchStartX
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}
}
const end = (event) => {
if (this._pointerEvent && PointerType[event.originalEvent.pointerType.toUpperCase()]) {
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this.touchDeltaX = event.originalEvent.clientX - this.touchStartX
}
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this._handleSwipe()
if (this._config.pause === 'hover') {
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// If it's a touch-enabled device, mouseenter/leave are fired as
// part of the mouse compatibility events on first tap - the carousel
// would stop cycling until user tapped out of it;
// here, we listen for touchend, explicitly pause the carousel
// (as if it's the second time we tap on it, mouseenter compat event
// is NOT fired) and after a timeout (to allow for mouse compatibility
// events to fire) we explicitly restart cycling
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this.pause()
if (this.touchTimeout) {
clearTimeout(this.touchTimeout)
}
this.touchTimeout = setTimeout((event) => this.cycle(event), TOUCHEVENT_COMPAT_WAIT + this._config.interval)
}
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}
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$(this._element.querySelectorAll(Selector.ITEM_IMG)).on(Event.DRAG_START, (e) => e.preventDefault())
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if (this._pointerEvent) {
$(this._element).on(Event.POINTERDOWN, (event) => start(event))
$(this._element).on(Event.POINTERUP, (event) => end(event))
this._element.classList.add(ClassName.POINTER_EVENT)
} else {
$(this._element).on(Event.TOUCHSTART, (event) => start(event))
$(this._element).on(Event.TOUCHMOVE, (event) => move(event))
$(this._element).on(Event.TOUCHEND, (event) => end(event))
}
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}
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_keydown(event) {
if (/input|textarea/i.test(event.target.tagName)) {
return
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}
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switch (event.which) {
case ARROW_LEFT_KEYCODE:
event.preventDefault()
this.prev()
break
case ARROW_RIGHT_KEYCODE:
event.preventDefault()
this.next()
break
default:
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}
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}
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_getItemIndex(element) {
this._items = element && element.parentNode
? [].slice.call(element.parentNode.querySelectorAll(Selector.ITEM))
: []
return this._items.indexOf(element)
}
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_getItemByDirection(direction, activeElement) {
const isNextDirection = direction === Direction.NEXT
const isPrevDirection = direction === Direction.PREV
const activeIndex = this._getItemIndex(activeElement)
const lastItemIndex = this._items.length - 1
const isGoingToWrap = isPrevDirection && activeIndex === 0 ||
isNextDirection && activeIndex === lastItemIndex
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if (isGoingToWrap && !this._config.wrap) {
return activeElement
}
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const delta = direction === Direction.PREV ? -1 : 1
const itemIndex = (activeIndex + delta) % this._items.length
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return itemIndex === -1
? this._items[this._items.length - 1] : this._items[itemIndex]
}
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_triggerSlideEvent(relatedTarget, eventDirectionName) {
const targetIndex = this._getItemIndex(relatedTarget)
const fromIndex = this._getItemIndex(this._element.querySelector(Selector.ACTIVE_ITEM))
const slideEvent = $.Event(Event.SLIDE, {
relatedTarget,
direction: eventDirectionName,
from: fromIndex,
to: targetIndex
})
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$(this._element).trigger(slideEvent)
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return slideEvent
}
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_setActiveIndicatorElement(element) {
if (this._indicatorsElement) {
const indicators = [].slice.call(this._indicatorsElement.querySelectorAll(Selector.ACTIVE))
$(indicators)
.removeClass(ClassName.ACTIVE)
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const nextIndicator = this._indicatorsElement.children[
this._getItemIndex(element)
]
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if (nextIndicator) {
$(nextIndicator).addClass(ClassName.ACTIVE)
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}
}
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}
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_slide(direction, element) {
const activeElement = this._element.querySelector(Selector.ACTIVE_ITEM)
const activeElementIndex = this._getItemIndex(activeElement)
const nextElement = element || activeElement &&
this._getItemByDirection(direction, activeElement)
const nextElementIndex = this._getItemIndex(nextElement)
const isCycling = Boolean(this._interval)
let directionalClassName
let orderClassName
let eventDirectionName
if (direction === Direction.NEXT) {
directionalClassName = ClassName.LEFT
orderClassName = ClassName.NEXT
eventDirectionName = Direction.LEFT
} else {
directionalClassName = ClassName.RIGHT
orderClassName = ClassName.PREV
eventDirectionName = Direction.RIGHT
}
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if (nextElement && $(nextElement).hasClass(ClassName.ACTIVE)) {
this._isSliding = false
return
}
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const slideEvent = this._triggerSlideEvent(nextElement, eventDirectionName)
if (slideEvent.isDefaultPrevented()) {
return
}
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if (!activeElement || !nextElement) {
// Some weirdness is happening, so we bail
return
}
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this._isSliding = true
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if (isCycling) {
this.pause()
}
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this._setActiveIndicatorElement(nextElement)
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const slidEvent = $.Event(Event.SLID, {
relatedTarget: nextElement,
direction: eventDirectionName,
from: activeElementIndex,
to: nextElementIndex
})
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if ($(this._element).hasClass(ClassName.SLIDE)) {
$(nextElement).addClass(orderClassName)
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Util.reflow(nextElement)
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$(activeElement).addClass(directionalClassName)
$(nextElement).addClass(directionalClassName)
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const nextElementInterval = parseInt(nextElement.getAttribute('data-interval'), 10)
if (nextElementInterval) {
this._config.defaultInterval = this._config.defaultInterval || this._config.interval
this._config.interval = nextElementInterval
} else {
this._config.interval = this._config.defaultInterval || this._config.interval
}
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const transitionDuration = Util.getTransitionDurationFromElement(activeElement)
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$(activeElement)
.one(Util.TRANSITION_END, () => {
$(nextElement)
.removeClass(`${directionalClassName} ${orderClassName}`)
.addClass(ClassName.ACTIVE)
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$(activeElement).removeClass(`${ClassName.ACTIVE} ${orderClassName} ${directionalClassName}`)
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this._isSliding = false
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setTimeout(() => $(this._element).trigger(slidEvent), 0)
})
.emulateTransitionEnd(transitionDuration)
} else {
$(activeElement).removeClass(ClassName.ACTIVE)
$(nextElement).addClass(ClassName.ACTIVE)
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this._isSliding = false
$(this._element).trigger(slidEvent)
}
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if (isCycling) {
this.cycle()
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}
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}
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// Static
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static _jQueryInterface(config) {
return this.each(function () {
let data = $(this).data(DATA_KEY)
let _config = {
...Default,
...$(this).data()
}
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if (typeof config === 'object') {
_config = {
..._config,
...config
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}
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}
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const action = typeof config === 'string' ? config : _config.slide
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if (!data) {
data = new Carousel(this, _config)
$(this).data(DATA_KEY, data)
}
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if (typeof config === 'number') {
data.to(config)
} else if (typeof action === 'string') {
if (typeof data[action] === 'undefined') {
throw new TypeError(`No method named "${action}"`)
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}
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data[action]()
} else if (_config.interval && _config.ride) {
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data.pause()
data.cycle()
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}
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})
}
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static _dataApiClickHandler(event) {
const selector = Util.getSelectorFromElement(this)
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if (!selector) {
return
}
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const target = $(selector)[0]
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if (!target || !$(target).hasClass(ClassName.CAROUSEL)) {
return
}
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const config = {
...$(target).data(),
...$(this).data()
}
const slideIndex = this.getAttribute('data-slide-to')
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if (slideIndex) {
config.interval = false
}
Carousel._jQueryInterface.call($(target), config)
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if (slideIndex) {
$(target).data(DATA_KEY).to(slideIndex)
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}
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event.preventDefault()
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}
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}
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/**
* ------------------------------------------------------------------------
* Data Api implementation
* ------------------------------------------------------------------------
*/
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$(document)
.on(Event.CLICK_DATA_API, Selector.DATA_SLIDE, Carousel._dataApiClickHandler)
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$(window).on(Event.LOAD_DATA_API, () => {
const carousels = [].slice.call(document.querySelectorAll(Selector.DATA_RIDE))
for (let i = 0, len = carousels.length; i < len; i++) {
const $carousel = $(carousels[i])
Carousel._jQueryInterface.call($carousel, $carousel.data())
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}
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})
/**
* ------------------------------------------------------------------------
* jQuery
* ------------------------------------------------------------------------
*/
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$.fn[NAME] = Carousel._jQueryInterface
$.fn[NAME].Constructor = Carousel
$.fn[NAME].noConflict = () => {
$.fn[NAME] = JQUERY_NO_CONFLICT
return Carousel._jQueryInterface
}
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export default Carousel