List in Dart

About

Lists in Dart are ordered collections of items.
They can store elements of the same type or mixed types.
Lists are zero-indexed, meaning the first element is at index 0.
Dart provides various list operations and methods for manipulation.

Main Topics

List Creation

Definition: How to create and initialize lists in Dart.

Example:

void main() {
  // Creating an empty list
  List<String> fruits = [];

  // Creating a list with initial values
  List<String> vegetables = ['Carrot', 'Potato', 'Spinach'];
}

List Operations

Definition: Methods for adding, removing, and accessing elements in a list.

Example:

void main() {
  List<String> fruits = ['Apple', 'Banana'];

  // Adding an element
  fruits.add('Orange');

  // Removing an element
  fruits.remove('Banana');

  // Accessing elements
  print(fruits[0]); // Outputs: Apple
}

List Types

Definition: Fixed-length vs. growable lists.

Example:

void main() {
  // Fixed-length list
  List<int> fixedList = List.filled(3, 0);
  fixedList[0] = 1;

  // Growable list
  List<int> growableList = [];
  growableList.add(1);
  growableList.add(2);

  print(fixedList); // Outputs: [1, 0, 0]
  print(growableList); // Outputs: [1, 2]
}

List Iteration

Definition: Techniques for looping through list elements.

Example:

void main() {
  List<String> fruits = ['Apple', 'Banana', 'Orange'];

  // Using a for loop
  for (int i = 0; i < fruits.length; i++) {
    print(fruits[i]);
  }

  // Using forEach
  fruits.forEach((fruit) {
    print(fruit);
  });
}

List Methods

Definition: Common methods for manipulating lists such as add(), remove(), insert(), and sort().

Example:

void main() {
  List<String> fruits = ['Apple', 'Banana', 'Orange'];

  // Adding an element
  fruits.add('Grapes');

  // Removing an element
  fruits.remove('Banana');

  // Inserting an element at a specific index
  fruits.insert(1, 'Blueberry');

  // Sorting the list
  fruits.sort();

  print(fruits); // Outputs: [Apple, Blueberry, Grapes, Orange]
}

How to Use

Creating a List: Use square brackets [] or the List constructor.
Accessing Elements: Use index notation (e.g., list[index]) to get or set elements.
Modifying Lists: Add, remove, or change elements using list methods.
Iterating: Use loops or methods like forEach to process list elements.

How It Works

Creation: Lists can be created with initial values or as empty.
Operations: Modify lists by accessing elements with indices and using methods for adding, removing, or updating.
Iteration: Loop through lists using for, forEach, or other iteration methods.
Types: Fixed-length lists have a set size, while growable lists can expand dynamically.

Example of List Operations:

void main() {
  // Creating a growable list
  List<String> fruits = ['Apple', 'Banana'];

  // Adding elements
  fruits.add('Orange');

  // Removing an element
  fruits.remove('Banana');

  // Accessing elements
  print(fruits[0]); // Outputs: Apple

  // Iterating through the list
  fruits.forEach((fruit) {
    print(fruit); // Outputs: Apple, Orange
  });
}

Conclusion

A List in Dart is a versatile collection that allows you to store ordered data. It supports various operations, such as accessing, modifying, adding, and removing elements, making it highly useful for scenarios where ordered data and duplicates are required.