Add elements to a list in Kotlin

This article explores different ways to add elements to a list in Kotlin.

1. Using `add()` function

The standard and recommended approach to add the specified element at the end of a mutable list is with the add() function.

fun main() {

val list: MutableList<Int> = mutableListOf(1, 2, 3) // or, use `arrayListOf`

list.add(4)

println(list) // [1, 2, 3, 4]

}

The add() function is not available for an immutable list. In the case of immutable lists, you can create a new list with the additional element.

fun main() {

var list = listOf(1, 2, 3) // var, not val

list += 4

println(list) // [1, 2, 3, 4]

}

If you need to add multiple elements to a mutable list, you can use the addAll() function.

fun main() {

val list: MutableList<Int> = arrayListOf(1, 2, 3)

list.addAll(listOf(4, 5))

println(list) // [1, 2, 3, 4, 5]

}

That’s all about adding elements to a list in Kotlin.