101403014 HW

[gmkevin00]

review?=@snowmantw
review?=@chungya
review?=@FlowerHop

Tier1 is finished.
I'm sorry about finishing this homework so late.

[snowmantw]

I prefer to use addEventListener('note-open', this) instead of binding on a function, since in this way all events could be redirected to this.handleEvent, and the this keyword in that method will refer to the instance you want to bind.

See this:
https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener#Example

[snowmantw]

Overall you need to understand the details of Promise and event handler API more, and consider how to improve your expressiveness. For a homework to gain enough scores of course is the first priority, but you will probably get int trouble when you have a coding job. And that's basically what I try to teach all of you.