CODEWITHSUNDEEP
androidkotlin
Jéwôm'
Jéwôm'

Reputation: 3971

Sort Map in reverse order in Kotlin

When I want to sort a Map I use :

map.toSortedMap()

But how can I sort a map in the reverse order?

For example my Map<Double, Int> is sorted with .toSortedMap(), so I have :

{0.01=10, 0.05=7, 0.1=8, 0.25=6, 0.5=15, 1.0=3, 2.0=9, 5.0=8, 10.0=14, 20.0=6, 50.0=10}

I would like something like:

{50.0=10, 20.0=6, 10.0=14, 5.0=8, 2.0=9, 1.0=3, 0.5=15, 0.25=6, 0.1=8, 0.05=7, 0.01=10}

Upvotes: 16

Views: 7831

Answers (3)

bkhong
bkhong

Reputation: 71

It is a bit late but hope this help.

for API <= 23

map.asIterable().reversed()

for API > 24

map.toSortedMap(Comparator.reverseOrder())

Upvotes: 4

m.fahad butt
m.fahad butt

Reputation: 9

Comparator.reverseOrder() works above the API level 21 ... the easiest way to get the keys from the sortedHashmap and reverse the keys list and then get values accordingly.

lateinit var entries: List<String>
entries = sortedList.keys.toList<String>()
entries = entries.reversed()
//get your values from map on the basis of keys

Upvotes: 0

zsmb13
zsmb13

Reputation: 89548

As @Venkata Raju said in the comment, you can use java.util.Comparator.reverseOrder() for this (available since 1.8):

map.toSortedMap(Comparator.reverseOrder())

You can also use the reverseOrder() function from the Kotlin standard library's kotlin.comparisons package:

map.toSortedMap(reverseOrder())

Upvotes: 20

Related Questions