How can I call try/catch in a Composable Button

Question

I need to catch a SQLiteException in a Composable Button click event. I am executing a Room function to Insert a record. It has a Unique constraint field/index.

I found the following code.

And found Stackoverflow link

I tried the accepted option and the third option, but did not work.

Here is my code:

ADO ///////

interface houseDAO {

@Insert(onConflict = OnConflictStrategy.ABORT )
@Throws(SQLiteException::class)
suspend fun addHouse(houseEntity: HouseEntity)

//More DAO functions

}

Repository ////////

class InventoryRepository (val inventoryDB: InventoryDB){

suspend fun addhouseToRoom(houseEntity: HouseEntity){
    inventoryDB.houseDao().addHouse(houseEntity)
}

 //More functions
}

Viewmodel //////////

class InventoryViewModel(val repository: InventoryRepository): ViewModel() {

fun addhouse(house: HouseEntity) {
    viewModelScope.launch {
        repository.addhouseToRoom(house)
    }
}

//More functions
}

Composable function ///////////

//More functions

Column(
            modifier = Modifier
                .padding(top = 22.dp, start = 6.dp, end = 6.dp)
                .fillMaxWidth(),
            horizontalAlignment = Alignment.CenterHorizontally
        ) {

            val coroutineScope = rememberCoroutineScope()

            //Commented line because the addfloor function does not returns any value  
            //val (loadResult, setLoadResult) = remember { mutableStateOf<String?>(null) }

            Button(
                onClick = {
                    coroutineScope.launch {
                        withContext(Dispatchers.IO) {
                            try {
                                viewModel.addfloor(
                                    FloorEntity(
                                        0,
                                        houseId!!.toLong(),
                                        infloor,
                                        "$location.$infloor"
                                    )
                                )
                                mToast("Floor Added", mContext)
                            } catch (e: SQLiteException) {
                                msgbox(
                                    mContext,
                                    e.message.toString(),
                                    "Floor Could not be Added"
                                )
                            }
                        }
                    }
                },
                colors = ButtonDefaults.buttonColors(Color.Blue)

            ) {
                Text(text = "Add Floor in to House")
            }
        }

//More functions    

The error is catched in another place on the application where I have a catch all errors segment.

Answer 1

I tried directly in the Viewmodel and it work.

DAO and Repository code is the same

Viewmodel ////////

fun addroom(mContext: Context, room: RoomEntity) {
   viewModelScope.launch {
       try {
           repository.addroomToRoom(room)
           msgbox(mContext, "", "Room Added")
       } catch (e: SQLiteException) {
           msgbox(mContext, e.message.toString(), "Room Could not be Added")
       }
   }
}

Composable Function ////////

Button(
                onClick = {
                        viewModel.addroom(mContext,
                            RoomEntity(
                                0,
                                floorId!!.toLong(),
                                inroomname,
                                inroomtype.value,
                                "$location.$inroomname"
                            )
                        )
                        //mToast("Room Added", mContext)
                },
                colors = ButtonDefaults.buttonColors(Color.Blue)

            ) {
                Text(text = "Add Romm into Floor")
            }

I removed the Toast message for simplicity and added the success message as part of the try code. I added the Context from the Compose function.