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/**
* --------------------------------------------------------------------------
* Bootstrap (v5.0.2): util/scrollBar.js
* Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
* --------------------------------------------------------------------------
*/
import SelectorEngine from '../dom/selector-engine'
import Manipulator from '../dom/manipulator'
import { isElement } from './index'
const SELECTOR_FIXED_CONTENT = '.fixed-top, .fixed-bottom, .is-fixed, .sticky-top'
const SELECTOR_STICKY_CONTENT = '.sticky-top'
class ScrollBarHelper {
constructor() {
this._element = document.body
}
getWidth() {
// https://developer.mozilla.org/en-US/docs/Web/API/Window/innerWidth#usage_notes
const documentWidth = document.documentElement.clientWidth
return Math.abs(window.innerWidth - documentWidth)
}
hide() {
const width = this.getWidth()
this._disableOverFlow()
// give padding to element to balance the hidden scrollbar width
this._setElementAttributes(this._element, 'paddingRight', calculatedValue => calculatedValue + width)
// trick: We adjust positive paddingRight and negative marginRight to sticky-top elements to keep showing fullwidth
this._setElementAttributes(SELECTOR_FIXED_CONTENT, 'paddingRight', calculatedValue => calculatedValue + width)
this._setElementAttributes(SELECTOR_STICKY_CONTENT, 'marginRight', calculatedValue => calculatedValue - width)
}
_disableOverFlow() {
this._saveInitialAttribute(this._element, 'overflow')
this._element.style.overflow = 'hidden'
}
_setElementAttributes(selector, styleProp, callback) {
const scrollbarWidth = this.getWidth()
const manipulationCallBack = element => {
if (element !== this._element && window.innerWidth > element.clientWidth + scrollbarWidth) {
return
}
this._saveInitialAttribute(element, styleProp)
const calculatedValue = window.getComputedStyle(element)[styleProp]
element.style[styleProp] = `${callback(Number.parseFloat(calculatedValue))}px`
}
this._applyManipulationCallback(selector, manipulationCallBack)
}
reset() {
this._resetElementAttributes(this._element, 'overflow')
this._resetElementAttributes(this._element, 'paddingRight')
this._resetElementAttributes(SELECTOR_FIXED_CONTENT, 'paddingRight')
this._resetElementAttributes(SELECTOR_STICKY_CONTENT, 'marginRight')
}
_saveInitialAttribute(element, styleProp) {
const actualValue = element.style[styleProp]
if (actualValue) {
Manipulator.setDataAttribute(element, styleProp, actualValue)
}
}
_resetElementAttributes(selector, styleProp) {
const manipulationCallBack = element => {
const value = Manipulator.getDataAttribute(element, styleProp)
if (typeof value === 'undefined') {
element.style.removeProperty(styleProp)
} else {
Manipulator.removeDataAttribute(element, styleProp)
element.style[styleProp] = value
}
}
this._applyManipulationCallback(selector, manipulationCallBack)
}
_applyManipulationCallback(selector, callBack) {
if (isElement(selector)) {
callBack(selector)
} else {
SelectorEngine.find(selector, this._element).forEach(callBack)
}
}
isOverflowing() {
return this.getWidth() > 0
}
}
export default ScrollBarHelper
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