How to animate Android Navigation Architecture fragment as sliding over old fragment?

Question

In example navigation action defined in navigation graph:

<action     android:id="@+id/action_fragment1_to_fragment2"     app:destination="@id/fragment2"     app:enterAnim="@anim/right_slide_in"     app:popExitAnim="@anim/left_slide_out"/> 

When Fragment2 opens and starts sliding into view from the right, Fragment1 disappears instantly (sadly). When Fragment2 is closed and starts sliding to the right, Fragment1 is nicely visible under it, giving a nice stack pop effect (comparable to iOS).

How can I keep Fragment1 visible while Fragment2 slides into view?

Answer 1

EDIT: This is not the most elegant solution, it is actually a trick but it seems to be the best way to solve this situation until the NavigationComponent will include a better approach.

So, we can increase translationZ (starting with API 21) in Fragement2's onViewCreated method to make it appear above Fragment1.

Example:

@Override public void onViewCreated(View view, Bundle savedInstanceState) {     super.onViewCreated(view, savedInstanceState);     ViewCompat.setTranslationZ(getView(), 100f); } 

As very nice @xinaiz suggested, instead of 100f or any other random value, we can use getBackstackSize() to assign to the fragment a higher elevation than the previous one.

The solution was proposed by @JFrite at this thread
FragmentTransaction animation to slide in over top
More details can be found there.