Android Navigation, I can move any fragment which is not connected

Issue

I am trying to use the Navigation architecture component in my toy app.

First I drew the fragments relationship in my "nav_graph.xml".

For example, I drew 3 fragments A, B, and C like below:

A -> B -> C

So I have 2 actions:

• action_a_to_b
• action_b_to_c

In general, I use the below code to move another fragment.

In A fragment,

findNavController().navigate(ADirections.actionAToB())

In B fragment,

findNavController().navigate(ADirections.actionBToC())

But you may know, there is another way to navigate. The fragment id can be used to navigate directly like below:

findNavController().navigate(R.id.a)

In my case, I don't have the action for A to C fragment. But if I use the below code in my A fragment, I can navigate!

findNavController().navigate(R.id.c)

Is it a bug? or intented?

Solution

This is intentional as per the documentation for navigate():

This supports both navigating via an action and directly navigating to a destination.

If you're using Safe Args, then only actions are supported. This ensures that you're only using the connections you've specified in your graph.

Answered By - ianhanniballake