Someone's Second 🧠

    Mvvm_Pattern

    MVVM

    Intro

    MVVM
    Model View ViewModel

    Doesn't define how VM communicates with VC and Model layer.
    You can use Functional Reactive programming, KVO pattern, Closures, Delegate pattern

    Swift UI embeds this thoroughly.

    Data Flow

    View controller < - > View Model < - > Model

    VM -> Speaks to View Controller.
    VM -> Speaks to Model

    Pros

    • VM - Business logic is separate
    • Easily testable
    • Dependency Injection | Separation of Concerns
    • SOLID principles
    • Promotes Reusability across diff platforms iOS, iPadOS, MacOS, WatchOS, Catalyst.
    • Great with Reactive paradigm

    Cons

    • View Controller still has bloated code.

    Code Example

    MVVM_example_SwiftUI

    References

    Dependency Injection
    singleton-dependency-injection-in-swift