Book Image

Android Development with Kotlin

By : Igor Wojda, Marcin Moskala
Book Image

Android Development with Kotlin

By: Igor Wojda, Marcin Moskala

Overview of this book

Nowadays, improved application development does not just mean building better performing applications. It has become crucial to find improved ways of writing code. Kotlin is a language that helps developers build amazing Android applications easily and effectively. This book discusses Kotlin features in context of Android development. It demonstrates how common examples that are typical for Android development, can be simplified using Kotlin. It also shows all the benefits, improvements and new possibilities provided by this language. The book is divided in three modules that show the power of Kotlin and teach you how to use it properly. Each module present features in different levels of advancement. The first module covers Kotlin basics. This module will lay a firm foundation for the rest of the chapters so you are able to read and understand most of the Kotlin code. The next module dives deeper into the building blocks of Kotlin, such as functions, classes, and function types. You will learn how Kotlin brings many improvements to the table by improving common Java concepts and decreasing code verbosity. The last module presents features that are not present in Java. You will learn how certain tasks can be achieved in simpler ways thanks to Kotlin. Through the book, you will learn how to use Kotlin for Android development. You will get to know and understand most important Kotlin features, and how they can be used. You will be ready to start your own adventure with Android development with Kotlin.
Table of Contents (16 chapters)
Title Page
About the Authors
About the Reviewers
Customer Feedback
Making Your Marvel Gallery Application

Named Kotlin function types

Kotlin does not support SAM conversions of types defined in Kotlin, because the preferred way is to use function types instead. But SAM has some advantages over classic function types: named function types and named parameters. It is good to have the function type named when its definition is long or it is passed multiple times as an argument. It is also good to have named parameters when it is not clear what each parameter means just by its type.

In the upcoming sections, we are going to see that it is possible to name both the parameters and the whole definition of a function type. This can be done with type aliases and named parameters in the function type. This way, it is possible to have all the advantages of SAM while sticking with function types.

Named parameters in function types

Until now, we've only seen definitions of function types where only the types were specified, but not parameter names. Parameter names have been specified in function literals: