How to create and edit events in ionic v1

The version I am using for my mobile is DayPilot Pro for JavaScript 2020.3.4610 (trial).

I was trying to create an event with a dropdown and ionic datepicker. But dropdown values are not getting binded. ionic datepicker is not even appearing.
I tried to show the view on creating an event by using daypilot modal.

I would also like to know how to close the modal while saving the event. I tried to close the modal while saving the event. But that also doesn't work. Given below is the code for the modal that I wrote.

var modal = new DayPilot.Modal({
saveEvent: function (args) {
console.log("Modal dialog closing");
modal.close();
},
onClosed: function (args) {
console.log("Modal dialog closed");
},
});
modal.showHtml("<div><h1>Create Event</h1><form><div><select ng-model='assignmentKey' ng-options='x.new for x in assignmentList | unique:'new'' ng-value='x.newKey'><option label=' Select '></option></select></div><div><button click='saveEvent()'>Save</button></div></form></div>");

Hope I will get a reply asap. Thanks in advance.