Dart - How to sort Map's keys

Question

I have question in sorting Map's key in Dart.

Map<String, Object> map = new Map();

How can I sort the keys in map? or Sort the Iterable map.keys.

Answer 1

If you want a sorted List of the map's keys:

var sortedKeys = map.keys.toList()..sort();

You can optionally pass a custom sort function to the List.sort method.

Finally, might I suggest using Map<String, dynamic> rather than Map<String, Object>?

Answer 2

In Dart, it's called SplayTreeMap:

import "dart:collection";

main() {
  final SplayTreeMap<String, Map<String,String>> st = 
      SplayTreeMap<String, Map<String,String>>();

  st["yyy"] = {"should be" : "3rd"};
  st["zzz"] = {"should be" : "last"};
  st["aaa"] = {"should be" : "first"};
  st["bbb"] = {"should be" : "2nd"};

  for (final String key in st.keys) {
    print("$key : ${st[key]}");
  }
}

// Output:
// aaa : first
// bbb : 2nd
// yyy : 3rd
// zzz : last

Answer 3

I know my answer is too late but check out what I've found.. Might help someone

This sortedmap Package helps to maintain Map of objects in a sorted manner.

Answer 4

final sorted = SplayTreeMap<String,dynamic>.from(map, (a, b) => a.compareTo(b));

As seen at

How to use a SplayTreeMap on Firebase snapshot dictionary in dart/Flutter?

Answer 5

map.entries.toList().sort(((a, b) => a.key.compareTo(b.key)));

I think so.