Subject is a special type in RxSwift that can act as both of these:
- An Observable sequence, which means it can be subscribed to
- An Observer that enables adding new elements onto a subject that will then be emitted to the subject subscribers
There are four subject types in RxSwift, each with unique characteristics that you may find useful in different scenarios. They are as listed:
- PublishSubject
- BehaviorSubject
- ReplaySubject
- Variable
Let's discuss each one of these subjects in turn.
A PublishSubject emits only new next events to its subscribers; in other words, elements added to a PublishSubject before a subscriber subscribes will not be received by that subscriber. This concept of emitting previous next events to new subscribers ...
