Object is not abstract and does not implement abstract base class member public abstract fun describeContents(): Int

[Aarav Shah]

import com.arkivanov.essenty.parcelable.Parcelable
import com.arkivanov.essenty.parcelable.Parcelize

sealed class RootGraph : Parcelable {
    @Parcelize object UserLibrary : RootGraph()
    @Parcelize object ExploreNewContent : RootGraph()
    @Parcelize object EventMaps : RootGraph()
    @Parcelize object LocalMusic : RootGraph()
   // @Composable
  //  abstract fun content(globalViewModel : GlobalViewModel)
}

I get error

• This class does not have a constructor
• Object is not abstract and does not implement abstract base class member public abstract fun describeContents(): Int defined in com.deathsdoor.chillback.common.ui.navigation.RootGraph but then i can't manually override the function if i want to

Also the doc is lacking , i mean so push function for router

[Isuru Rajapakse]

Hi. Thanks for the issue. Have you included the parcelize plugin on your module?

This is required for android, just like any other android module

[Aarav Shah]

Yes i tried with parcelize plugin , and different versions of the 'optional' (other) libraries as well but i get that issue. If i but @parcelize on the class itself i get , Object is not abstract and does not implement abstract base class member public abstract fun describeContents(): Int defined in some decompose package. As well as , I am unable to 'find' the methods given in the doc

[Isuru Rajapakse]

I see what the issue is.

You should only need to annotate with @Parcelize once on the top-level sealed class. Here's the sample implementation

@Parcelize
sealed class StoryHomeScreen: Parcelable {
  object List: StoryHomeScreen()
  data class Details(val section: TopStorySection, val uri: ArticleUri, val title: String): StoryHomeScreen()
}

The documentation is wrong and I will use this issue to correct this. Thanks for pointing this out 👍 Hopefully the above fix works for you

[Aarav Shah]

Thanks , that solved the issue and since you are fixing the README , maybe change

  val commonMain by getting {
    dependencies {
      implementation("io.github.xxfast:decompose-router:${versions.decompose-router}")

      // You will probably need to also bring in decompose and essenty
      implementation("com.arkivanov.decompose:decompose:${versions.decompose}")
      implementation("com.arkivanov.decompose:extensions-compose-jetbrains:${versions.decompose}")
      implementation("com.arkivanov.essenty:parcelable:${versions.essenty}")
    }
  }

as the other libraries are needed else you can't use the router at all

[Isuru Rajapakse]

Yup will do

[Arkadii Ivanov]

I have just checked and the original code works for me just fine. I mean, kotlin-parcelize plugin should work both ways. Not sure what was the actual issue.

[Isuru Rajapakse]

yeah, you are right @arkivanov, I'm assuming the issue was an outdated cache prior to adding kotlin-parcelize

Nevertheless, I've update the readme (in #15) to go with the simpler approach of declaring @Parcelize once on the sealed type