Has anyone had any luck with having a Material3 ModalBottomS

Question

Has anyone had any luck with having a Material3 ModalBottomSheet backHandler work I see there s an existing issue <https issuetracker google com issues 271303558> Just wondering if anyone has found a workaround or any particular way of implementing a backHandler to get it working I m basically not wanting the back button to hide the ModalBottomSheet but it does no matter what

Mahmoo · Answer

you have modalBottomSheetState right you can use the state to hide it Also if you want that when system back button is pressed then use back handler

bryankeltonadams · Answer

I don t have any issues using the state to hide it the issue is that my ModalBottomSheet has navigation inside of it and if I hit the backButton on a screen that I navigate to inside of the sheet it just closes the sheet instead of navigating back I ve tried putting a backHandler inside of the ModalBottomSheet and right outside of it and neither get triggered The backHandler worked fine when I was using a ModalBottomSheetLayout with Material but since I ve migrated to Material3 I have not figured out how to do any sort of back handling with the ModalBottomSheet

Mahmoo · Answer

Can you try this Keep the body of your backHandler empty this should help

Mahmoo · Answer

try by keeping the backHandler empty

Zoltan Demant · Answer

Are you using `android enableOnBackInvokedCallback= true ` The sheet intercepts key events and with this enabled the new back event is ignored the sheet just takes the old event into account Disabling it should allow you to use BackHandler to do anything you like

ascii · Answer

Because of <https kotlinlang slack com archives C04TPPEQKEJ p1695306835513579 thread ts=1695298775 663439 amp cid=C04TPPEQKEJ> I believe custom BackHandlers cannot override M3 sheet s default back handling You ll have to put your navigation logic in ModalBottomSheet s `onDismissRequest` because that is called when you press back or tap on the scrim etc

ascii · Answer

So you could check nav back stack in that callback and choose to not hide the sheet I m not a 100 sure because I haven t done this specifically myself

bryankeltonadams · Answer

Zoltan I don t believe I have this enabled is it enabled if it isn t disabled though

Zoltan Demant · Answer

I m 99 on it being opt in rather than opt out

bryankeltonadams · Answer

Okay yeah I for sure don t have this in my manifest and I put a BackHandler outside of the Sheet and inside as well

bryankeltonadams · Answer

Adhiraj if I put something in my onDismissRequest the sheet will still be put into a hidden state when the backButton is pressed right But then in my onDismissRequest I d have to check if the screen I am on is not the first screen in my navigation reshow the sheet and popBackStack But then there d be weird visual behavior of pressing the back button would make the sheet close open and then navigate to where it s supposed to go

ascii · Answer

It s been a while since I worked with M3 sheets and that s the part I m not sure about Perhaps overriding `confirmStateChange` or whatever it s called along with `onDismissRequest` will get you what you want

ascii · Answer

So if nav has a back stack confirmStateChange should return false if it s transitioning from Expanded gt Hidden true otherwise

ascii · Answer

Test it and see if it behaves like I think it would

ascii · Answer

You d override confirm in `rememberModalBottomSheetState`

bryankeltonadams · Answer

I tried just immediately returning false in the function and it doesn t do anything

bryankeltonadams · Answer

Even with removing onDismissRequest all that happens is false is returned when the function is called but the sheet still slides down into a Hidden state

bryankeltonadams · Answer

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