What methods exist for data exchange between user interface components in an application?

There are several ways to exchange data between user interface components in an Android application:

• Intent and Bundle — for passing data between Activities or Fragments.
• ViewModel and LiveData — for exchanging data between fragments within the same Activity, providing reactive UI updates.
• SharedPreferences — for saving and reading simple data.
• EventBus (e.g., Otto library or GreenRobot EventBus) — for passing events between components.
• Shared object or singleton — for storing and accessing data from different parts of the application.

Example with ViewModel and LiveData:

class SharedViewModel : ViewModel() {
    val selectedItem = MutableLiveData<String>()
}

// In Fragment A
viewModel.selectedItem.value = "Data to pass"

// In Fragment B
viewModel.selectedItem.observe(viewLifecycleOwner) { data ->
    // update UI with new data
}