CODEWITHSUNDEEP
angularangular-materialangular7
mruanova
mruanova

Reputation: 7115

Angular: create is deprecated: use new Observable() instead

I recently updated my version of angular using ng update and when running ng lint

I am getting the error create is deprecated: use new Observable() instead

this.data$ = Observable.create(t => {
    t.next(this.model);
    t.complete();
});

What is the syntax for new observable?

Upvotes: 55

Views: 44243

Answers (5)

Sergey
Sergey

Reputation: 7682

Pretty simple

this.data$ = new Observable((observer: Observer) => {
  observer.next();
  observer.complete();
});

Updated answer

this.data$ = new Observable<void>((observer) => {
  observer.next();
  observer.complete();
});

Instead of void you can put any type your observable is supposed to emit. Observer's next value type will be inferred for the callback.

Upvotes: 88

Mohamud Abshir
Mohamud Abshir

Reputation: 21

on NgOnInt create custom observable like this

ngOnInit() {

const customObservable = new Observable((observer: Observer<object>){
  observer.next(this.modal);
  observer.complete();
})

subscribe it

this.customSubscription = customObservable.subscribe((data) => {

  // logic goes here 
})

}

later on, in ngOnDestroy unsubscribe it

ngOnDestroy() {
    this.customSubscription.unsubscribe();
}

Upvotes: 2

Anik Saha
Anik Saha

Reputation: 4494

In 2021 it is changed.

new Observable((observer: Observer<object>) => {
    observer.next(data);
});

instead of

new Observable((observer: Observer) => {
    observer.next();
    observer.complete();
});

Upvotes: 17

Muhammad Bilal
Muhammad Bilal

Reputation: 1999

observableSubscription: Subscription;

Creating Custom Observable

const observer = new Observable((observer: Observer) => {
   observer.next();
   observer.error();
   observer.complete();
});

Subscribing To Custom Observable

this.observableSubscription = observer.subscribe((data:any) => {
   console.log(data);
})

Unsubscribing

this.observableSubscription.unsubscribe();

Upvotes: 7

Abel Valdez
Abel Valdez

Reputation: 2408

Or you can use just 

this.data$ = of(this.model);

Upvotes: 10

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