Angular2/4 - Cannot read property subscribe of undefined

Question

I am new to Angular and recently start to learn it by reading a book 'ng-book The Complete Book on Angular 4'. In the 'how angular works' chapter I wrote a small inventory app followed by the instructions on the book but having issue after startup, shown as below: error log on browser console

All my components seem alright and the errors are just not seem relevant to my code. I even compared to the example code downloaded and they look very identical.

I know it's probably not that much of a big deal and I should move on and go back to this when I gain more knowledge. But really it's bothering me...

Not sure what's the best way of showing all my source code here so I created a shareable google drive link and a .zip with everything in that project can be retrieved by the link. ANY HELP WILL BE HIGHLY APPRECIATED!!!

https://drive.google.com/file/d/0B76fFkACV6wRdmtJU0Jfc0J4U1U/view?usp=sharing

By the way, the project was created by angular cli. And a smaller .zip with only src can be accessed by drive.google.com/file/d/0B76fFkACV6wRbkY2M1p5NHRnUW8/… — Jay.Z
– Jay.Z, Commented Jun 14, 2017 at 12:03
pro tip: to showcase full code you could use github, specially if your projects are open source :) — Jota.Toledo
– Jota.Toledo, Commented Jun 14, 2017 at 12:09

Sherif Behna · Accepted Answer · 2017-06-14 12:23:28Z

9

In ProductsListComponent, you need to change :

@Output() onProductSelected: EventEmitter<Product>;

to :

@Output() onProductSelected = new EventEmitter<Product>();

Also, remove the line in ngOnInit in the same component.

The event emitter needs to be initialized when the class is created. See this example : http://learnangular2.com/outputs/

answered Jun 14, 2017 at 12:23

Sherif Behna

6135 silver badges4 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Jay.Z Over a year ago

Spot on! Thank you so much

Collectives™ on Stack Overflow

Angular2/4 - Cannot read property subscribe of undefined

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related