Sort collection by multiple fields in Kotlin

sortedWith + compareBy (taking a vararg of lambdas) do the trick:

val sortedList = list.sortedWith(compareBy({ it.age }, { it.name }))

You can also use the somewhat more succinct callable reference syntax:

val sortedList = list.sortedWith(compareBy(Person::age, Person::name))

Use sortedWith to sort a list with Comparator.

You can then construct a comparator using several ways:

  • compareBy, thenBy construct the comparator in a chain of calls:

    list.sortedWith(compareBy<Person> { it.age }.thenBy { it.name }.thenBy { it.address })
    
  • compareBy has an overload which takes multiple functions:

    list.sortedWith(compareBy({ it.age }, { it.name }, { it.address }))
    

Tags:

Kotlin