Randomly select an item from a List in Kotlin

This article explores different ways to randomly select an item from a List in Kotlin.

1. Using `random()` function

Since Kotlin 1.3, you can use the random() function to return a random element from a list. A typical invocation for this method would look like below. Note that it throws NoSuchElementException if the list is empty.

fun main() {

val values = (1.. 10).toList()

val random = values.random()

println(random)

}

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2. Using `Random.nextInt()` function

Before Kotlin 1.3, you can generate a random index and use that index to get the random value. This can be achieved using the Random.nextInt() function, which returns a random value uniformly distributed between 0 (inclusive) and the specified bound (exclusive).

import kotlin.random.Random

fun <T> getRandomElement(list: List<T>): T {

val randomIndex = Random.nextInt(list.size)

return list[randomIndex]

}

fun main() {

val values = (1.. 10).toList()

val random = getRandomElement(values)

println(random)

}

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3. Using `shuffled()` function

Another solution is to randomize the list using the shuffled() function, and return the value present at the first or the last index. This would translate to a simple code below:

fun main() {

val values = (1.. 10).toList()

val random = values.shuffled()[0]

println(random)

}

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That’s all about randomly selecting an item from a List in Kotlin.

Randomly select an item from a List in Kotlin

1. Using random() function

2. Using Random.nextInt() function

3. Using shuffled() function

Share this:

1. Using `random()` function

2. Using `Random.nextInt()` function

3. Using `shuffled()` function