List([int length])

Creates a list of the given length.

The created list is fixed-length if length is provided.

List fixedLengthList = new List(3);
fixedLengthList.length;     // 3
fixedLengthList.length = 1; // Error

The list has length 0 and is growable if length is omitted.

List growableList = new List();
growableList.length; // 0;
growableList.length = 3;

To create a growable list with a given length, just assign the length right after creation:

List growableList = new List()..length = 500;

The length must not be negative or null, if it is provided.

Source

external factory List([int length]);