How to prevent previous fragment to show up after pressing back button using navigation controller?

Navigation offers a popUpTo and popUpToInclusive attributes for removing fragments from the back stack as part of a navigate() operation.

This can be set either in XML:

<!-- Add to your Navigation XML, then use navigate(R.id.go_home) -->
<action
  android:id="@+id/go_home"
  app:destination="@+id/home_fragment"
  app:popUpTo="@+id/destination_to_pop"
  app:popUpToInclusive="true"/>

Or set it programmatically:

NavOptions navOptions = new NavOptions.Builder()
    .setPopUpTo(R.id.destination_to_pop, true)
    .build();
Navigation.findNavController(view).navigate(homeDestination, navOptions)

You can also use the id of a <navigation> element as well.