How to use indexOf in kotlin for ArrayList of a data class?

Question

In kotlin, I have a data class like this:

data class MyModel (
    val key: String,
    val myValue: String
)

I have an ArrayList of above model:

val myList: ArrayList<MyModel>

I don't know how to get the index of an element by passing the key:

fun getPosition(key: String): Int = myList.indexOf(/* what to do here? */)

----edit----

Assume that keys are unique.

I am implementing ItemKeyProvider in RecyclerView in android, for that I needed to know this. — Akshdeep Singh
– Akshdeep Singh, Commented Jun 24, 2019 at 9:38

tynn · Accepted Answer · 2019-06-24 09:22:52Z

9

You can use indexOfFirst which receive a functional parameter:

fun getPosition(key: String): Int = myList.indexOfFirst { it.key == key }

answered Jun 24, 2019 at 9:22

tynn

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