Implementing abstract functions with the same name twice

Android
1

Hello! I’m a beginner with Kotlin, but taking small steps. However, I’ve had to examine some code, and the existing code contains this:

public interface Bob {
public abstract fun onError(err: com.abc.def.ErrorResponse): kotlin.Unit
public abstract fun onError(err: com.abc.def.HardwareError): kotlin.Unit
}

In my code, I have typed:
AFragment.newInstance(“identifier”, myListener =
object : Bob{
override fun onError(err: ErrorResponse) {
}
override fun onError(err: HardwareError) {
}
})

However, I get a compiler error "Object is not abstract and does not implement abstract member public abstract fun onError(err: HardwareError): Unit defined in com.abc.def.Bob

If I comment out one or the other “override fun onError…” snippets, then the compiler error just moves from on of the onError definitions to the other. So, I believe I’m not implementing those abstract functions properly, but googling isn’t helping : ( If I could, I’d work around the problem by changing the original abstract declarations so that the functions had different names, but I cannot do that unfortunately.

I think I should be using the keyword super? But I’m not sure if I’m heading in the wrong direction. Any direct help, or even tips, would be great. Apologies if this was a very trivial issue.

2

Please ignore, I’ve solved it. The solution was to use autocomplete properly in Android Studio, and it changed the second onError parameter to com.abc.def.HardwareError
Now it compiles fine.

3

You can look into function overloading if you want to better understand what’s going on, and how functions with the same name (but different parameters) work

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