IssueTracker

In order navigate using "NavDirection" directly created from a ViewModel would it be possible to pass R.string.id as argument?

Imagine a case where multiple errors leads you to a fragment that differs only by its text. Same behavior inside but only information change sightly. You would try to re-use that common part and avoid duplication.

If you try to generate a direction from your ViewModel with argument you won't be able to retrieve context assosiated string to fill the label. So would it be possible to parse a dynamic label's id instead of applying a toString() on it?

Currently if I send a NavDirection with an argument in it which is also {label} it will just apply a toString() and show id in place of toolbar title. Expected is the localised string as title to not resolve it using getString by myself (in a fragment, before or after navigation)

• Sample project to trigger the issue.

   // snippet from nav_graph.xml
   <fragment
        android:id="@+id/FailureWithTitle"
        android:name="com.example.MyFragment"
        android:label="{title}" >
        <argument
            android:name="title"
            app:type="resource" />
   </fragment>
   <fragment
        android:id="@+id/firstFragemnt"
        android:name="com.example.MyFirstFragment"
        android:label="title" >
        <action 
               android:id="@+id/navigateToFailureWithTitle"
               ansdroid:destination= "@id/failureWithTitle"
        />
   </fragment>

   // snippet from strings.xml
   <string name="failure_invalid_request">Failure</string>
   <string name="failure_timeout">Timeout</string>
   <string name="failure_not_found">Not Found</string>

Some snippets from the way I would otherwise do it.

// viewModel
val navigateTo = MutableLiveData<NavDirection>()

private fun navigate() {
  when(case) {
   case0 -> navigateTo.post(MyFragmentAction.navigateToSuccess())
   case1 -> navigateTo.post(MyFragmentAction.navigateToFailureWithTitle(R.string.failure_invalid_request))
   case2 -> navigateTo.post(MyFragmentAction.navigateToFailureWithTitle(R.string.failure_timeout))
   case3 -> navigateTo.post(MyFragmentAction.navigateToFailureWithTitle(R.string.failure_not_found))
}

// Fragment
viewModel.navigateTo.observe(viewLifeCycleOwner, Observer { findNavController().navigateToDirection(it) } )

Current work around would be to create one destination per string_id reusing the same fragment "name" attribute and duplicate actions.

This would also remove the need of "getString()" logic from fragment or hook the "onDestinationChanged" as suggested some places just to update a title.