Developers have been using Android Studio for developing apps which cater to several use cases. They mostly use Java or Kotlin for native app development. Java has several open-source tools and libraries that prove helpful for developers. Kotlin can introduce new solutions to prevalent use cases and enhance the Java ecosystem.
Kotlin has gradually grown as the language of choice among the developer community. Several developers prefer Kotlin as it is precise, and it can make life easier for them as it reduces the risk of errors. There is an inbuilt null safety feature, and it is interoperable with Java.
We will discuss more the importance of Java and Kotlin in Android Studio Native app development.
Importance of using Java
The prime importance of Android development arises from the need to design a platform-agnostic application which can run on any device. It can run on a unique virtual machine and on all devices on which it is loaded. Java has extensive libraries, and developers can quickly leverage them. The Android SDK has several Java libraries. Several resources have proficiency in the language. They can help design and improve applications with several libraries and Java tools.
Importance of using Kotlin
Kotlin is another option available for Android development. Developers can write code faster, and it is a statically typed language. It ensures code security and enhances developer productivity. You can focus on creating quality code without concentrating on the boilerplate areas. It is fully interoperable with Java too.
When you are using Kotlin, you can easily avoid NullPointerExceptions due to the presence of @NonNull and @Nullable in the type system. When you use Kotlin, the applications are less likely to crash. It can streamline asynchronous programming and request database updates and network calls.
Critical features in Kotlin
Declaring Variable
Variables can be declared using two keywords: viz. val and var.
Val can be used for variables where the value does not change. If the variable was declared using val, you could not reassign a value.
Var is used to name a variable whose value can change.
Null Safety
You can declare a reference type variable without providing any initial explicit value. Here, the variables can have a null value. Remember that variables in Kotlin can’t hold null values by default. The nullable variables must be handled carefully to prevent any NullPointerException.
Conditional logic
You can deploy conditional logic in several ways. In the if-else statement, when the expression is wrapped in parenthesis next to the if keyword and is evaluated to a true, the code in that branch can be executed. Else, the code in the else part gets executed.
Functions
Several expressions can be grouped into a function. It is better to have the expressions in a function and call the function when needed. You can use the fun keyword and have the function name after that. The body is where the expressions can be defined and are called when the function gets invoked. When declaring a function, you can specify several arguments and their types.
Simplify function declarations
You can use the generateAnswerString() function as it is simple. It can declare a variable and return it immediately. The result of the expression is returned from the function, and you can skip declaring the local variable directly. The assignment operator can replace the return keyword.
Higher order functions
A function in Kotlin can also take another in an argument. They are called higher order functions. It can help communication, like using a callback interface in Java. The stringMapper() function can take a String with the function to derive an Int value from the String, which can be passed into it.
Classes
If you want to add your type, you can use a class. The class will represent the state with properties. A class can be declared using the “class” keyword. The property is a class-level variable with a setter, getter, and a backing field. The functions can modify the state and help expose the required data.
SAM conversion
You can implement the OneClickListener interface and listen for click events in Android. It has a single abstract method, oneClick(), which must be implemented. You can use SAM conversion for cleaner code. For example, setOnClickListener() will take OnClickListener as argument. OnClickListener has the same single abstract method and can be represented as an anonymous function in Kotlin. This is called the Single Abstract method (SAM) conversion.
Companion objects
The companion objects can define functions or variables which are conceptually linked to a type. However, they are not tied to any particular object. They are like Java’s static keywords for methods and variables. TAG can be defined at the file’s top level. But, the file can itself have several functions, variables, and classes.
