The Observer pattern yana bayyana one-to-many dependency inda abubbuwa da yawa (observers) suke auna jiya-jiya lokacin da wani abu (the subject) ya canja state. Yana ba da damar decoupled, event-driven communication — ana amfani da shi sosai a cikin UIs, event systems, da reactive programming.
Abin da Observer pattern ya yi
OBSERVER → a SUBJECT maintains a list of OBSERVERS and NOTIFIES them on state changes:
→ observers SUBSCRIBE to the subject
→ when the subject changes → it notifies ALL subscribed observers automatically
→ observers react to the notification (update themselves)
→ one-to-many: one subject, many observers; DECOUPLED (subject doesn't know observer details)
