W3cubDocs

/Kotlin

indexOf

open fun indexOf(element: @UnsafeVariance E): Int

Returns the index of the first occurrence of the specified element in the list, or -1 if the specified element is not contained in the list.

© 2010–2017 JetBrains s.r.o.
Licensed under the Apache License, Version 2.0.
https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/-abstract-list/index-of.html