如何将引导工具提示放在SVG上？

getPosition: function (insidE) {
  var el = this.$element[0]
  var width,height

  if ('http://www.w3.org/2000/svg' === el.namespaceURI) {
      var bBox = el.getBBox()
      width = bBox.width
      height = bBox.height
  } else {
      width = el.offsetWidth
      height = el.offsetHeight
  }

  return $.extend({},(inside ? {top: 0,left: 0} : this.$element.offset()),{
    'width': width,'height': height
  })
}