How does the implementation of interaction between View and logic differ in MVVM patterns and other architectural approaches?

In the MVVM (Model-View-ViewModel) pattern, interaction between the View and logic occurs through the ViewModel, which acts as an intermediary and abstracts the logic from the interface.

Features of MVVM:

• The View subscribes to changes in the ViewModel (for example, via LiveData or Observable).
• The ViewModel does not know about the specific implementation of the View, which enhances testability and separation of concerns.

In other architectures, such as MVC or MVP:

• In MVC, the View directly interacts with the Model or Controller.
• In MVP, the Presenter manages the View and Model, but the View is usually more passive.

Example in MVVM with Kotlin and LiveData:

class MyViewModel : ViewModel() {
    val data = MutableLiveData<String>()

    fun loadData() {
        data.value = "Hello, MVVM!"
    }
}

// In Activity or Fragment
viewModel.data.observe(this) { value ->
    textView.text = value
}