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@camera.ui/sdk / observable / BehaviorSubject

Class: BehaviorSubject<T> ​

Defined in: observable/index.ts:253

Subject seeded with an initial value that always remembers the latest emission. New subscribers receive the current value immediately on subscribe() and then all subsequent values. The current value is also accessible synchronously via value and getValue().

Extends ​

Type Parameters ​

T ​

T

Constructors ​

Constructor ​

new BehaviorSubject<T>(initialValue): BehaviorSubject<T>

Defined in: observable/index.ts:256

Parameters ​

initialValue ​

T

Returns ​

BehaviorSubject<T>

Overrides ​

Subject.constructor

Accessors ​

closed ​

Get Signature ​

get closed(): boolean

Defined in: observable/index.ts:130

Whether complete() has already run.

Returns ​

boolean

Inherited from ​

Subject.closed


value ​

Get Signature ​

get value(): T

Defined in: observable/index.ts:292

The most recently emitted value.

Returns ​

T

Methods ​

asObservable() ​

asObservable(): Observable<T>

Defined in: observable/index.ts:242

Returns a read-only Observable that mirrors this Subject without exposing next() or complete(). Useful for handing out a public stream while keeping write access internal.

Returns ​

Observable<T>

Read-only Observable view of this Subject.

Example ​

ts
const subject = new Subject<number>();
export const events$ = subject.asObservable();

Inherited from ​

Subject.asObservable


complete() ​

complete(): void

Defined in: observable/index.ts:160

Release every subscriber and lock the Subject. Later next() calls are ignored.

Returns ​

void

Example ​

ts
subject.complete();

Inherited from ​

Subject.complete


getValue() ​

getValue(): T

Defined in: observable/index.ts:287

Read the current value without subscribing.

Returns ​

T

The most recently emitted value.

Example ​

ts
const current = state$.getValue();

next() ​

next(value): void

Defined in: observable/index.ts:272

Store value as the current one and dispatch it to every subscriber.

Parameters ​

value ​

T

New current value.

Returns ​

void

Example ​

ts
const state$ = new BehaviorSubject('idle');
state$.next('recording');

Overrides ​

Subject.next


pipe() ​

Call Signature ​

pipe(): Observable<T>

Defined in: observable/index.ts:215

Chain operators onto this Subject's read-only view.

Returns ​

Observable<T>

Observable emitting the transformed values.

Example ​
ts
subject.pipe(distinctUntilChanged()).subscribe((state) => console.log(state));
Inherited from ​

Subject.pipe

Call Signature ​

pipe<A>(op1): Observable<A>

Defined in: observable/index.ts:216

Chain operators onto this Subject's read-only view.

Type Parameters ​
A ​

A

Parameters ​
op1 ​

OperatorFn<T, A>

Returns ​

Observable<A>

Observable emitting the transformed values.

Example ​
ts
subject.pipe(distinctUntilChanged()).subscribe((state) => console.log(state));
Inherited from ​

Subject.pipe

Call Signature ​

pipe<A, B>(op1, op2): Observable<B>

Defined in: observable/index.ts:217

Chain operators onto this Subject's read-only view.

Type Parameters ​
A ​

A

B ​

B

Parameters ​
op1 ​

OperatorFn<T, A>

op2 ​

OperatorFn<A, B>

Returns ​

Observable<B>

Observable emitting the transformed values.

Example ​
ts
subject.pipe(distinctUntilChanged()).subscribe((state) => console.log(state));
Inherited from ​

Subject.pipe

Call Signature ​

pipe<A, B, C>(op1, op2, op3): Observable<C>

Defined in: observable/index.ts:218

Chain operators onto this Subject's read-only view.

Type Parameters ​
A ​

A

B ​

B

C ​

C

Parameters ​
op1 ​

OperatorFn<T, A>

op2 ​

OperatorFn<A, B>

op3 ​

OperatorFn<B, C>

Returns ​

Observable<C>

Observable emitting the transformed values.

Example ​
ts
subject.pipe(distinctUntilChanged()).subscribe((state) => console.log(state));
Inherited from ​

Subject.pipe

Call Signature ​

pipe<A, B, C, D>(op1, op2, op3, op4): Observable<D>

Defined in: observable/index.ts:219

Chain operators onto this Subject's read-only view.

Type Parameters ​
A ​

A

B ​

B

C ​

C

D ​

D

Parameters ​
op1 ​

OperatorFn<T, A>

op2 ​

OperatorFn<A, B>

op3 ​

OperatorFn<B, C>

op4 ​

OperatorFn<C, D>

Returns ​

Observable<D>

Observable emitting the transformed values.

Example ​
ts
subject.pipe(distinctUntilChanged()).subscribe((state) => console.log(state));
Inherited from ​

Subject.pipe

Call Signature ​

pipe<A, B, C, D, E>(op1, op2, op3, op4, op5): Observable<E>

Defined in: observable/index.ts:220

Chain operators onto this Subject's read-only view.

Type Parameters ​
A ​

A

B ​

B

C ​

C

D ​

D

E ​

E

Parameters ​
op1 ​

OperatorFn<T, A>

op2 ​

OperatorFn<A, B>

op3 ​

OperatorFn<B, C>

op4 ​

OperatorFn<C, D>

op5 ​

OperatorFn<D, E>

Returns ​

Observable<E>

Observable emitting the transformed values.

Example ​
ts
subject.pipe(distinctUntilChanged()).subscribe((state) => console.log(state));
Inherited from ​

Subject.pipe


subscribe() ​

subscribe(callback): Disposable

Defined in: observable/index.ts:308

Register callback and invoke it immediately with the current value.

Parameters ​

callback ​

(value) => void

Receiver invoked once per emitted value.

Returns ​

Disposable

Disposable that unregisters the callback.

Example ​

ts
const sub = state$.subscribe((state) => console.log(state));

Overrides ​

Subject.subscribe