question about nullable types - as an example, let...

# android

[Abhi]

question about nullable types - as an example, let's say I have a util method in java with signature:

public static void showDialog(@NonNull FragmentActivity activity)

and I call it within a fragment using kotlin as Util.showDialog(fragment.activity). The compiler complains that Expected: FragmentActivity, Found: FragmentActivity? Knowing that the activity will not be null when I call the method (i:e I call it right after onActivityCreated()), which of the following would be a good way to handle the error:

- casting: fragment.activity as FragmentActivity
- non null assertion: fragment.activity!!
- let/if blocks (but this will hide the exception and hurt me in the long run)

[Lucas Ribeiro]

activity will be nullable because it's a system type (Activity!), you can change the showDialog() function to accept Activity? and verify inside the function if it's not

[Abhi]

thanks lucas, that's a good approach, but I stated a contrived example. In the actual util method, I need the activity to be non-null. so I am thinking !! is the best way out