通用kotlin里面的通用

Question

I have some abstract class BaseViewModel , BaseActivity .

abstract class BaseViewModel<N> : ViewModel(){}

My purpose using N to pass as an interface into it, and when any viewModel extends to BaseViewModel , just pass its navigator into.

But I got a problem when write BaseActivity .

abstract class BaseActivity<T : ViewDataBinding,V: BaseViewModel<???>> : AppCompatActivity() {}

what it should be?

Answer 1

You mean like this?

abstract class BaseViewModel<N> : ViewModel(){}

abstract class BaseActivity<T : ViewDataBinding,V: BaseViewModel<Test>> : AppCompatActivity() {}

interface Test

You can make it even more protected, if you extend from base interface:

abstract class BaseViewModel<N:BaseTest> : ViewModel(){}

abstract class BaseActivity<T : ViewDataBinding,V: BaseViewModel<Test>> : AppCompatActivity() {}

interface Test:BaseTest

interface BaseTest

In that case, if you interface doesn't inherit generic's parent class, compiler will give you an error of compilation.