Quick question as a sanity check: Is it true that ...

# compose

[Filip Wiesner]

Quick question as a sanity check:
Is it true that when using View(XML)-based navigation components, the multi-backstack navigation and state saving is enabled by default but when implementing navigation via compose, we need to specify it ourselves like in this example.

[Filip Wiesner]

And by "enabled by default" I mean provided by bottomNav.setupWithNavController(controller).
Compose navigation does not have such "connector" provided by the nav library.

[Ian Lake]

Correct

[Filip Wiesner]

And why is it the dafault in View-based navigation when material spec says that the state shouldn't be saved? 🤔

On Android, revisiting a section resets the app, returning the user to its top-level screen.

[Filip Wiesner]

And is it just omission of such "connector" in Compose navigation or is it not meant to be the default behavior?
Sorry for possibly dumb questions. I am just a little confused 😅 I started debugging old app and the nav behavior was different than I am used to from the Compose world

[Ian Lake]

The material docs are out of date and haven't yet been updated (they were true when it wasn't possible to save state. Now it is possible)

[Ian Lake]

Compose doesn't impose using Material components or Material3 components: you can use any set of components you want. A connector made a lot less sense than just pointing out the three lines you can use with any bottom nav / drawer implementation you want

[Filip Wiesner]

Fair enough, thank you Ian 👍

[Filip Wiesner]

One sort of follow-up question:
Let's say I have a bottom nav with items A and B and another screen C which is opened from A. I start on screen A (as a start destination), navigate to C and then switch to B using bottom navigation. Now I am at B but C should be saved in a "separate back stack" meaning that C should be displayed when I navigate to A, correct?
So now when I
1. navigate from B to A using bottom nav the C is displayed ✅
2. navigate from B to A using the system back button, the A is displayed ❔ Not sure if this is correct or not.
3. navigate from B to A using the system back button (I am at A), navigate back to B using bottom nav (I am at B) and navigate to A using bottom nav, I would expect to land on A because I just was at A and the state was not restored but I end up back on C - the back stack was restored. Is this expected behavior? Because it does not feel right.
I would either expect to A->C saved back stack be removed when I pop up to start destination or restored same way as with navigating.

[Filip Wiesner]

😶 and not Compose, I know but I couldn't find anyone else with this question so I though I'll ask here.