Can't access date in ember-pikaday onSelection from the outside

Has any of you experienced this using the ember-pikaday addon? I would like to set the date from the onSelection to be stored on the selectedDate but the context inside the onSelection is of the addon and not of the component itself. Is there a way I could store the value of date to one of the properties in my component?

My code is like this:

import Ember from 'ember';

export default Ember.Component.extend({
  classNames: ['schedule-nav-date-picker'],
  selectedDate: null,

  onSelection: function(date) {
    this.set('selectedDate', date);
    return date;
  },

  actions: {
    saveClicked () {
        this.sendAction('saveClicked', this.get('selectedDate'));
    },

    cancelClicked () {
      this.sendAction('cancelClicked');
    }

  }
});

And it gives me this error:

pikaday.js:165 Uncaught TypeError: this.get(...) is not a function
at Class.userSelectedDate (pikaday.js:165)
at Class.onPikadaySelect (pikaday.js:151)
at Backburner.run (ember.debug.js:224)
at Backburner.join (ember.debug.js:247)
at Function.run.join (ember.debug.js:15904)
at Pikaday.<anonymous> (ember.debug.js:15966)
at Pikaday.setDate (pikaday.js:815)
at HTMLDivElement.Pikaday.self._onMouseDown (pikaday.js:462)