Angular update 8.1 - circular dependency warning

Question

Since updating to Angular 8.1 (8.0 worked), I'm getting a circular dependency warning that doesn't really make sense to me.

I have an Injectable Service SelectService that is provided in some components. The service is using a class SelectableItem. When creating an instance of this class, the service itself is passed as an argument.

item = new SelectableItem(
   ...
   this
);

The SelectableItemclass is not Injectable and looks like this.

export class SelectableItem {
    constructor(..., public selectService: SelectService) { }
}

Now since the 8.1 update i get a circular dependecy warning:

selectable-item.ts -> select.service.ts -> selectable-item.ts

SelectableItem is not a service, how can it be a circular dependency?

I think the problem come from how you import class. Can you add it to your question ? — Martin Choraine, Jul 22 '19 at 09:07
@MartinChoraine what do you mean by import? The class is imported with `import { SelectableItem } from './../models/selectable-item';` there is not much special about that. — Thomas Schneiter, Jul 22 '19 at 09:16
Ok this is what I wanted to verify. I already meet this issue when using barrel import. But it's not your case — Martin Choraine, Jul 22 '19 at 09:27

score 0 · Answer 1 · answered Jul 22 '19 at 09:19

Your SelectService class should look something like this. With the dependency to SelectableItem as a property of the service class.

import "SelectAbleItem" from "../selectable-item.ts

@Injectable()
class SelectService {
}

private selectItem: SelectItem;
public get SelectItem():SelectItem { return this.selectItem; }

Now in the constructor of the SelectableItem don't inject the SelectService but rather use the injector to provide it.

class SelectableItem {
  constructor() {
    const injector = Injector.create([{provide: SelectService, useClass: SelectService, deps: [SelectableItem]]};
    const selectService = injector.get(SelectService);
  }
}

I got some code from here and here. The code isn't tested and may contain a small glitch but it should point you in the right direction.

I still get the same error when using the Injector. The code is [here](https://github.com/Crazyht/ngx-tree-select/tree/dev/src/ngx-tree-select/src), it's not my repo i'm just trying to fix it. — Thomas Schneiter, Jul 22 '19 at 09:33

Angular update 8.1 - circular dependency warning

1 Answers1