39 lines
936 B
JavaScript
39 lines
936 B
JavaScript
let cached
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export default function getScrollBarSize (fresh) {
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if (fresh || cached === undefined) {
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const inner = document.createElement('div')
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inner.style.width = '100%'
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inner.style.height = '200px'
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const outer = document.createElement('div')
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const outerStyle = outer.style
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outerStyle.position = 'absolute'
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outerStyle.top = 0
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outerStyle.left = 0
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outerStyle.pointerEvents = 'none'
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outerStyle.visibility = 'hidden'
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outerStyle.width = '200px'
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outerStyle.height = '150px'
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outerStyle.overflow = 'hidden'
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outer.appendChild(inner)
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document.body.appendChild(outer)
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const widthContained = inner.offsetWidth
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outer.style.overflow = 'scroll'
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let widthScroll = inner.offsetWidth
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if (widthContained === widthScroll) {
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widthScroll = outer.clientWidth
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}
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document.body.removeChild(outer)
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cached = widthContained - widthScroll
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}
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return cached
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}
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