I m using compose nav and currently have a destination defin

Question

I m using compose nav and currently have a destination defined as ``` dogdetails dogId ``` but now I need to update it to take in a list array of dogIds It ll typically be 1 id but can support 2+ I saw the docs talk about adding a list in another section of navigation but it looks like all I d need is NavType IntArrayType but I m not sure how to create the string path Do I just take my array and call tostring on it and compose nav knows how to handle it Edit Looks like no matter what I try to get IntArray working I just keep getting a `java lang UnsupportedOperationException Arrays don t support default values `

Ian Lake · Answer

Did you see the gt `NavDeepLink` now supports default values for arrays which allows support for repeated query params that will map to the argument s array type `NavType` also now includes a default method which can be overridden to combine two parsed values So you d be able to write ` dogDetails dogId= dogId ` and include multiple ids when you navigate e g `dogDetails dogId=47 amp dogId=74 amp dogId=12`

Colton Idle · Answer

Interesting I m not using this for deepLinks but so it sounds like having a path arg be an array isn t possible I need to make it an arg instead of a path

Colton Idle · Answer

e g this wont work ```composable dogs dogIds arguments = listOf navArgument dogIds defaultValue = intArrayOf 1 type = NavType IntArrayType DogPage it arguments getIntArray dogIds ```

Ian Lake · Answer

You can certainly write your own `NavType` that parses the string `dogdetails 47 74 12` or `dogdetails 47 74 12 ` into an array but you need to define what that parsing is

Ian Lake · Answer

You can t just `toString` an array

Colton Idle · Answer

Gotcha The above compiles fine i know that thats meaningless but it does compile fine with java lang UnsupportedOperationException Arrays don t support default values so maybe that just led me down the wrong path

Ian Lake · Answer

But if you use `dogDetails dogId= dogId ` you can certainly use `type = NavType IntArrayType` directly

Colton Idle · Answer

Gotcha I guess I just misunderstood path navtypes vs arg nav types

Colton Idle · Answer

Tried updating to 2 6 0 beta01 and backQueue is now private release notes dont mention a backup property to use any tips on that

Colton Idle · Answer

FWIW i didn t write this but a previous team member wrote ```repeat backQueue size popBackStack ``` im assuming thats not great see no evil

Ian Lake · Answer

That s never been a part of the public API surface and that code actually pops way too many times since backQueue also counts navigation graphs not just screens You ll want to popBackStack to the root graph s route

Ian Lake · Answer

Colton Idle · Answer

So just something like this would work fine ```popBackStack StartDestination route true ```

Colton Idle · Answer

oh i misunderstood i think you mean that navHost itself takes a route very interesting i think maybe i knew that

Colton Idle · Answer

i wonder if just using my start destination would work also

Colton Idle · Answer

This call to navigate doesn t seem to work The default value always gets populated instead Am i missing something ```val dogIdArray = intArrayOf 2 HomeScreen navController navigate dogDetail dogIds=$dogIdArray ```

Ian Lake · Answer

That s not what I said gt include multiple ids when you navigate e g `dogDetails dogId=47 amp dogId=74 amp dogId=12`

Ian Lake · Answer

You re still just `toString `ing an array

Colton Idle · Answer

Oh I guess i completed whiffed this So I just need to do `dogId=47 amp dogId=74 amp dogId=12` etc

Colton Idle · Answer

i guess that makes sense man this ate up so much of my day this whole stringly typed stuff just has a lot of foot guns I honestly dont even know why NavType IntArray even let me use it at all in 2 5 x anyway just venting because this soaked up my time looking forward to type safe args crossed fingers

dewildte · Answer

< Ian Lake> Please correct me if I am wrong but It s not so bad if you consider the route to be a URL If you know how a URL works then it makes what you can and can not do in the route far more clear