index Of
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.
Since Kotlin
1.2Returns 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.
Since Kotlin
1.0Returns 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.
Since Kotlin
1.1Returns 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.