Insert an element into a BehaviorSubject

How can I insert an item into a BehaviorSubject?

I want to add an item with an expanded name in each object. Here's what I have tried so far:

Answer №1

Is this the kind of thing you're looking for?

this.someService.retrieve()
  .watch(responses => {
    const editedResponses = responses.map(entry => ({...entry, modified: false}));
    this.data.receive(editedResponses)
});

Answer №2

It seems you are looking to include the expanded property in the array of values for BehaviorSubject.

Here is a way to achieve this: BehaviorSubject has a value property that holds the most recent data emitted.

this.dates.value.forEach(item => (item.expanded = true));
console.log(this.dates.value);

Please remember to modify the data before emitting the next value, as suggested by @Bojan Kogoj, to ensure that all current subscribers receive the updated data.

Answer №3

My typical approach in handling this task involves the following steps:

private update$ = new BehaviorSubject(null);

fetchData$(): Observable<Order[]>{
    return this.update$.pipe(switchMap(()=>
            this.http.get<Order[]>(`${this._url}/orders`)));
  }

Answer №4

If you're looking to include the 'expanded' attribute in every object within an array, consider implementing the following approach:

private dataSubject: BehaviorSubject<any> = new BehaviorSubject<any>(this.data);
public dataObservable$: Observable<any> = this.dataSubject.asObservable();

this.dataSubject.next(response); // Assign your data object and subscribe to the observable

this.dataObservable$.subscribe(dataObs => {
  dataObs.forEach(item => {
    if (item && !item['expanded']) {
      item['expanded'] = false;
    }
  })
})

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