Method _getMonthInCurrentYear

src/material/datepicker/year-view.ts:325–329

* Gets the month in this year that the given Date falls on. * Returns null if the given Date is in another year.

(date: D | null)

   * Returns null if the given Date is in another year.
   */
  private _getMonthInCurrentYear(date: D | null) {
    return date && this._dateAdapter.getYear(date) == this._dateAdapter.getYear(this.activeDate)
      ? this._dateAdapter.getMonth(date)
      : null;
  }

  /**
   * Takes a month and returns a new date in the same day and year as the currently active date.