IssueTracker

Component used: Navigation / Safe args
Version used: 1.0.0-alpha-01
Devices/Android versions reproduced on: -

Safe args are a great enhancement for navigation. A great addition to that would be being able to define nullability for arguments. An example for how this would look like:

        <argument android:name="id" app:type="string?"/>

(note the ? for the type) - an alternative would be to have another attribute - e.g. app:required="false" to make it less tied to Kotlin. The generated Args and NavDirections class would have the Nullable/NonNull annotations.
This would make it very obvious which arguments are required and which are optional - especially in Kotlin.