infogo-tree/src/store/utils.ts

A vue tree component using virtual list.

function getStyleComputedProperty(element: any, property: any) {
  // NOTE: 1 DOM access here
  const css = window.getComputedStyle(element, null)
  return css[property]
}
const getScrollParent: any = (element: any) => {
  const parent = element.parentNode

  if (!parent) {
    return element
  }

  if (parent === window.document) {
    // Firefox puts the scrollTOp value on `documentElement` instead of `body`, we then check which of them is
    // greater than 0 and return the proper element
    if (window.document.body.scrollTop || window.document.body.scrollLeft) {
      return window.document.body
    } else {
      return window.document.documentElement
    }
  }

  // Firefox want us to check `-x` and `-y` variations as well
  if (
    ['scroll', 'auto'].indexOf(getStyleComputedProperty(parent, 'overflow')) !== -1 ||
    ['scroll', 'auto'].indexOf(getStyleComputedProperty(parent, 'overflow-x')) !== -1 ||
    ['scroll', 'auto'].indexOf(getStyleComputedProperty(parent, 'overflow-y')) !== -1
  ) {
    // If the detected scrollParent is body, we perform an additional check on its parentNode
    // in this way we'll get body if the browser is Chrome-ish, or documentElement otherwise
    // fixes issue #65

    return parent
  }
  return getScrollParent(element.parentNode)
}
export {
  getScrollParent,
}