In the vibrant world of Flutter development, understanding Dart data structures plays a crucial role in creating efficient applications. Dart - a strongly typed, object-oriented programming language developed by Google, similar to other programming languages, makes use of a variety of data structures that assist developers in storing, organizing, and accessing their Dart data more effectively.
Dart data structures are specific ways of organizing data in a software program that allows it to be used efficiently. They're crucial for effectively handling Dart data, making our code more organized, faster, and easier to understand. Now, let's move toward a deeper understanding of the Dart collections available to us.
Generally, in most programming languages, an array is used to define a collection of elements. But Dart, being unique, defines this collection using Lists instead of an array. Lists, also known as Arrays in other programming languages, are Dart's way of storing multiple items in a single variable. They can store elements of the same type or of different types.
A List can either be a fixed length list or a growable list. A fixed length list has a defined size and it cannot change. On the other hand, a growable list does not have a defined size, you can add or remove elements in it.
Here is a simple code snippet on how we use Lists in Dart:
1 void main() { 2 List <String> logTypes = new List<String>(); 3 logTypes.add("WARN"); 4 logTypes.add("ERROR"); 5 logTypes.add("INFO"); 6 7 // iterating across list 8 for(String type in logTypes) { 9 print(type); 10 } 11 } 12
The 'var list = []' is exactly the same object used to create a list literal. This showcases Dart's inherently flexible and intuitive syntax.
Dart provides a number of utility functions to manipulate collections in Dart. Some selected functions include adding elements, removing elements, sorting a list, and much more. These functions help to make interactions with collections easier.
A set is an unordered collection of unique items, exactly the same object can't appear more than once in a Dart set.
Just like we defined a list using the 'var list = []' syntax, we can define a set with the 'var set = ' syntax, which makes it a set literal. Similar to this, an empty set can be defined using Set() as its constructor.
For example:
1 void main() { 2 Set <String> countries = new Set <String>(); 3 countries.add("USA"); 4 countries.add("India"); 5 countries.add("China"); 6 7 print("Countries: $countries"); 8 } 9
There are various methods available for handling and managing sets in Dart. Some of these include methods for adding a single element, multiple elements, removing an element, and checking if the set contains an element.
A map in Dart is a collection which contains key-value pairs. The-keys can be any type and they point to a value of any type. It should be noted that the keys in a Dart map are unique.
Defining a map is as simple as 'Map map = ', making it a map literal. For example:
1 void main() { 2 Map scoreBoard = {"Dart" : 85, "Java" : 60, "Python" : 75}; 3 4 print("Dart Score: ${scoreBoard["Dart"]}"); 5 } 6
The Map collection in Dart provides utility functions making the operations on key-value pairs more efficient. Methods include functionality to add new key-value pairs, remove particular entries, update a value for a specified key, and many more.
A queue in Dart, a part of dart:collection is a collection of items following the sequence in which they were added—ensuring that the first element added is the first one to come out (FIFO: First in, First out). This collection doesn't allow random access to its elements.
1 import 'dart:collection'; 2 3 void main() { 4 Queue<int> queue = new Queue<int>(); 5 print("Default implementation ${queue.runtimeType}"); 6 queue.addLast(10); 7 queue.addLast(20); 8 queue.addLast(30); 9 queue.addLast(40); 10 queue.removeFirst(); 11 12 for(int no in queue){ 13 print(no); 14 } 15 } 16
Various methods to work with queues include addLast(), addFirst(), removeFirst(), removeLast() etc.
A Multi-Dimensional array can be defined as an array of arrays, this data structure is mostly used for storing multi-dimensional data such as a table of values.
1 void main() { 2 List<List<int>> matrix = [ 3 [1, 2, 3], 4 [4, 5, 6] 5 ]; 6 7 print(matrix); 8 } 9
Similar to arrays, we can have multi-dimensional maps in Dart as well. It is a map within another map. It's used to store data which can't be represented conveniently by a one-dimensional map.
1 void main() { 2 Map<String, Map<String, int>> graph = { 3 "vertex1": { 4 "vertex2": 1, 5 "vertex3": 6 6 }, 7 "vertex2": { 8 "vertex1": 1 9 }, 10 "vertex3": { 11 "vertex1": 6 12 } 13 }; 14 15 print(graph); 16 } 17
A queue in Dart, a part of dart:collection is a collection of items following the sequence in which they were added—ensuring that the first element added is the first one to come out (FIFO: First in, First out). This collection doesn't allow random access to its elements.
1 import 'dart:collection'; 2 3 void main() { 4 Queue<int> queue = new Queue<int>(); 5 print("Default implementation ${queue.runtimeType}"); 6 queue.addLast(10); 7 queue.addLast(20); 8 queue.addLast(30); 9 queue.addLast(40); 10 queue.removeFirst(); 11 12 for(int no in queue){ 13 print(no); 14 } 15 } 16
Dart's data structures, arrays, sets, maps, and queues each have their unique aspects, and knowing when to use which is vital. Arrays are best when you want to keep an ordered list of items. Sets become valuable when you need to assure that you only have one of each item. Maps excel at storing key-value pairs, and Queues come into play when the order of operations matters.
Remember following key points for efficient use of data structures:
The efficient use of Dart's data structures can greatly help make your Dart programming and Flutter development experience smoother and your apps more performant.
Once you start building Flutter applications, getting well-versed in Dart and its data structures becomes increasingly important. Maps, sets, lists, and queues in Dart data structures are used extensively, and mastering them can be an actual game-changer. An in-depth understanding of Dart collections and Dart data structures will help you write cleaner, faster, and more efficient code – thereby giving you a considerable edge in your Flutter development journey.
So, that's a run-down on some of the key Dart Data Structures and how to use them effectively. No overstating, gaining proficiency in these will put you at an advantage when dealing with Dart data. Ultimately, they are just tools in your developer toolbox, and knowing when to use them can make you a far more effective programmer. After all, writing code that's efficient and clear is what we all strive for, right?
In the journey of coding, there will be a number of times you'll file feature requests, go through the release process, or even work towards publishing automation, but stepping stones like understanding the core elements at play are equally important. So, delve into coding, experiment, learn and never hesitate to explore. Happy Coding!
Tired of manually designing screens, coding on weekends, and technical debt? Let DhiWise handle it for you!
You can build an e-commerce store, healthcare app, portfolio, blogging website, social media or admin panel right away. Use our library of 40+ pre-built free templates to create your first application using DhiWise.