opened event mentioned in the documentation does not exist.

[gmoneh]

The documentation mentions that an "opened" event will be fired when the calendar is opened, but this is not true, no such event exists.

[dasnein]

I also faced this problem. As a solution, you can fork this repository and add 'opened' emitter yourself in Datepicker.vue file in setInitialView() method

setInitialView () {
  const initialView = this.computedInitialView
  if (!this.allowedToShowView(initialView)) {
    throw new Error(`initialView '${this.initialView}' cannot be rendered based on minimum '${this.minimumView}' and maximum '${this.maximumView}'`)
  }
  switch (initialView) {
    case 'year':
      this.showYearCalendar()
      break
    case 'month':
      this.showMonthCalendar()
      break
    default:
      this.showDayCalendar()
      break
  }
  if (!this.isInline) {
    this.$emit('opened')
  }
}