Foo is final, I dont get it

# getting-started

[ursus]

Foo is final, I dont get it

[ursus]

No it doesnt because generic param is not part of any public api, that is exactly what confuses me. Callsite cant see Quax in any form

[ursus]

unless im missing something

[ursus]

basically its this

class FooFragment : BaseFragment<FooViewMode> {

	override fun onCreateViewModel() {
		return FooViewModel()
	}
}

class BaseFragment<T> {
	protected lateinit var viewModel: T

	override fun onCreateView(view: View) { <-- framework
		viewModel = onCreateViewModel()
	}

	protected abstract fun onCreateViewModel() : T
}

[ursus]

i.e. FooViewModel is implementation detail of FooFragment, I see no reason to expose it publicly; viewModel reference is protected inside BaseFragment hierarchy..idk

[ursus]

how? its protected

[ursus]

You cant, im trying it right now

[ursus]

Compilers dont understand visibility?

[ursus]

isnt this some sort of javainterop bs? I think protected is also package private in java

[ursus]

I dont get it what you mean, if it gets change to public it wont compile, same how if private function returns a private class, and you change it to public it wont compile

[ursus]

im still not sure why does the param need to be public, im trying even simpler example

class Bar : Foo<Quax>() 

abstract class Foo<T>

internal class Quax

error is public sublcass exposes internal supertype argument

[ursus]

Btw it works in java with package private T_T

[ursus]

public class Rah extends Meh<Ohe> {
}

class Ohe {
}

abstract public class Meh<T> {
}

[ursus]

this is precisely what I want in kotlin (swap package private for internal)

[ursus]

it only complains if Ohe is private (nested)