Dart – Sort a List
In Dart programming, the List data type is similar to arrays in other programming languages. A list is used to represent a collection of objects. It is an ordered group of objects. The core libraries in Dart are responsible for the existence of the List class, its creation, and manipulation. Sorting of the list depends on the type of list we are sorting i.e. if we are sorting an integer list then we can use a simple sort function whereas if it is a string list then we use compareTo to sort the list.
There are two main data types which are stored in List:
- Integer
- String
We will learn to sort both of them in the article below.
1. Sorting an Integer List
An integer list can be sorted by the simple sort function.
Example: Sorting an integer list.
// Main function
main() {
// Creating List
List<int> w3wiki = [13, 2, -11, 142, -389, 32, 3032, 0];
// Sorting List
w3wiki.sort();
// Printing Sorted List
print(w3wiki);
}
Output:
[-389, -11, 0, 2, 13, 32, 142, 3032]
2. Sorting a String List
The string is sorted by comparing the length in the sort function.
Example: Sorting a string list.
// Main function
main() {
// Creating list of string
List<String> w3wiki = ['one', 'two', 'three', 'four'];
// Sorting string by comparing the length
w3wiki.sort((a, b) => a.length.compareTo(b.length));
// Printing the list
print(w3wiki);
}
Output:
[one, two, four, three]
If we use sort without comparing the length then:
Example: Sorting a string list without comparing the length.
// Main function
main() {
// Creating list of string
List<String> w3wiki = ['one', 'two', 'three', 'four'];
// Sorting string without
// comparing the length
w3wiki.sort();
// Printing the list
print(w3wiki);
}
Output:
[four, one, three, two]
Example: Using the cascades method while sorting the list.
// Main function
main() {
// Creating list of string
List<int> w3wiki = [13, 2, -11, 142, -389, 0];
// Sorting string and Printing the list
print(w3wiki..sort());
}
Output:
[-389, -11, 0, 2, 13, 142]