Kotlin is poised to become the new language for Android development. With Google’s recent announcement of making Kotlin an official language for Android app development, it won’t be long before you start seeing more Kotlin code at work. The time has come to take the plunge and make the switch from Java to Kotlin! In this article, we’ll cover some key features of Kotlin that will save you time when developing your next Android app, and maybe even inspire you to pick up this exciting new language.
Read Detailed Blog: Kotlin vs Java: Which is Better for Android App Development?
10 Kotlin Features that Boost Android Development
1. Null Safety
Null Safety is a feature of Kotlin which prevents NullPointerException. Kotlin will throw a compile-time error instead of Runtime Exception if any variable is null. This minimizes your risk of getting exceptions and makes you write more robust code. As a leading Android app development company in the UK, our expert developers use libraries that have external APIs to interface with them, so there is always a chance of getting null values from these APIs.
Using Null Safety in your code makes it really simple for other programmers who read your code and helps to prevent crashes at runtime because of Null Pointer Exceptions. You can convert Java code into Kotlin, when you see an exclamation mark in front of a variable type then it means, don’t worry about possible null values, they won’t occur until runtime.
2. Static Layout Import
It automatically adds all views, attributes and drawables to your layout code in a subdirectory. Static imports are good practice, both when you import classes (import android.R.id.*; instead of android.R.*) and when you import members (import com.google.android.*; instead of com.google.*). This reduces boilerplate code and makes it much easier to read and maintain your code—especially in complex layouts with nested elements. For example, if you use Java-style nesting, adding a view takes 4 lines of code instead of 7
3. Writing POJO Classes with Kotlin
Writing POJO Classes with Kotlin is easy and can be very powerful. While Java is still a great language, it is verbose and requires much more boilerplate code than Kotlin. With Kotlin’s classes, it’s quite easy to achieve many common design patterns without any additional framework support.
The most powerful tool in Kotlin when writing POJO classes is delegated properties: All you need to do is specify one property as the delegate of another property, like below: class SimpleClass(val prop1: String by DelegateProperty(prop2)) //OR class SimpleClass(var prop1: String?
4. Kotlin Comes With Lazy-Loading Feature
What’s Lazy-Loading Feature? It is a new feature introduced in Kotlin 1.1 beta and is currently on RC3. With lazy loading, we no longer need to worry about objects being created at incorrect times and memory leaks resulting from this. At last, it makes our applications more elegant and scalable. Unlike similar features in other languages (like C#), Kotlin’s lazy loading also allows us to define object dependencies during runtime rather than requiring them to be defined when a class is compiled.
5. Data Classes in Kotlin
Data classes make working with data structures in Kotlin much easier. When we define a data class, Kotlin automatically generates getters and setters for each of its properties. If you find yourself using Java’s default no-arg constructors (the ones with just a public String name;) then it’s time to move up to Kotlin’s data classes, which give you all of their functionality without any of their hassle.
If you find yourself in need of a standard way to interact with serialized Java objects, your first thought might be something like
6. Collection Filtering
An extension function for collections called filter can be used to filter out elements from a collection based on a provided Predicate. This is useful if you have a collection of items and you want to get rid of certain ones in order to reduce their size or avoid certain elements.
7. Extension Functions
Kotlin makes it easier to write code that can run on both Java and Kotlin platforms. Extension functions allow you to write a function in Kotlin, but make it available as if it were written in Java (or vice versa). What’s great about extension functions is they don’t have to be declared ahead of time. Instead, you’re writing them right where you need them—so say goodbye to static utility methods!
8. Reduces Crashes at Runtime
It’s a commonplace mantra of Android development: Write less code to achieve more. The Kotlin programming language is an opportunity to move in that direction. Its tooling, library, and collection of new language features help developers make it even easier for themselves—reducing crashes at runtime and increasing productivity. This post outlines 10 key features from Kotlin v1.0 you can use to build better apps with fewer bugs on Google Play now.
9. Smart Cast Function
Thanks to the Smart Cast function, you can store any object into a variable and check if it was created from an Activity or Fragment. If yes, any interface methods will be called with just one line of code (e.g., findViewById()) instead of many lines of boilerplate casts. In case it wasn’t created by Fragment/Activity then those interface calls will not be invoked.
10. Safe and Reliable
Kotlin is a programming language based on Java. It’s safe and reliable due to its strong object-oriented design, null safety, and type inference. Language designers make sure it won’t lead to a crash in production or your users can lose data. Thus, you can focus on solving business problems rather than worrying about code correctness and performance optimization.
If you’re serious about your mobile development efforts, I recommend giving Kotlin a shot. After all, why keep coding against a static language? Although it’s true that Kotlin is not 100% interoperable with Java right now, there are libraries like Kotlin tools or Kotlin-android-extensions to help bridge the gap. But even if you don’t have time to learn it, for now, consider adding a Kotlin/Native compilation step to your build pipeline; at least use it as inspiration for feature ideas on your next project! It’s really difficult to get started with a new language and ecosystem but once you do, you’ll find new ways of thinking about common problems and eventually have more confidence in your code.