My business layer doesn t include Compose but I d like a met

Question

My business layer doesn t include Compose but I d like a method in it to suspend while waiting for the user to respond to a dialog Showing the dialog uses ` Composable` which doesn t exist in the business layer Any patterns on how to structure that I ll put what I have so far in the thread

David W · Answer

Business module ``` suspend fun installFromUnknownSource promptUserToReplaceExistingFolder suspend modInfo ModInfo gt Boolean ```

David W · Answer

Dialog ``` Composable suspend fun DuplicateModAlertDialog modInfo ModInfo Boolean return suspendCoroutine cont gt stuff cont resume ```

David W · Answer

Usage the part that doesn t compile due to lacking Composable ```installFromUnknownSource promptUserToReplaceExistingFolder = modInfo gt DuplicateModAlertDialog modInfo ```

David W · Answer

can t tell if i m being dumb or trying to do something that shouldn t be done not mutually exclusive

Adam Powell · Answer

You might be interested in how `SnackbarHostState` publishes data for composables to display It uses a suspend function to show a notification and get a return value for whether the snackbar was dismissed or if the user pressed a button for that message <https cs android com androidx platform frameworks support + androidx main compose material material src commonMain kotlin androidx compose material SnackbarHost kt l=60 q=SnackbarHostState amp sq=|https cs android com androidx platform frameworks support + androidx main compose material material src commonMain kotlin androidx compose material SnackbarHost kt l=60 q=SnackbarHostState amp sq=>

David W · Answer

Very interesting thank you Took me a bit to get a chance to look So it essentially decouples the Snackbar from the listener Calling `showSnackbar` creates a new observable state that contains a continuation then suspends The Snackbar is then created shown in response to the newly created state and invokes the continuation when the user interacts with it

David W · Answer

Having that singleton state variable is the decoupling that s needed to allow the communication between the layer without Composable and the layer with

Adam Powell · Answer

right And since it s state it can be presented in 0 N places simultaneously if the situation calls for it

Adam Powell · Answer

nothing is consumed unless it s acted on and it doesn t particularly matter which presentation is acted on

Adam Powell · Answer

and if the caller of `showSnackbar` no longer cares it can cancel its call and it will be removed from the queue if it was currently being shown it will move on to the next one

David W · Answer

canceling the suspending call with invoke ```finally currentSnackbarData = null ```

David W · Answer

and from there the next suspending call which was waiting for the Mutex will start creating a new toast

Adam Powell · Answer

Yep