Kotlin sintax overview

This talk is result of my presentation on AndroidStudyJams Maceió

Transcript

1. Kotlin for Android Felipe Oliveira oliveiradev
2. Felipe Oliveira
3. Linguagem foi criada pela JetBrains, Kotlin roda na JVM e é 100% interoperável com Java.
5. Sintaxe overview: atributos
6. Sintaxe overview: métodos
7. Sintaxe overview: classes class Person {} open class Person {} data class Person(val name: String, val age: Int)
8. Sintaxe overview: Null safety val person: Person? = Person("Felipe",24) fun main(args: Array<String>) { print(person?.name) }
9. Sintaxe overview: Default arguments fun query(table: String, columns: Array<String>, orderBy: String? = null, limit: Int? = null){ ... } query("PEOPLE", arrayOf("ID","NAME")) query("PEOPLE", arrayOf("ID","NAME") , limit = 10)
10. Sintaxe overview: Extension functions fun ImageView.loadForUrl(url: String){ Picasso.with(context).load(url).into(this) } //single expression sintax fun String.hello() = "Hello $this"
11. Sintaxe overview: When expression when(value){ is String -> print("eh String") else -> print("n eh String") }
12. Sintaxe overview: Smart cast if (value is String){ print(value.length) }
13. Instalando plugin no Android Studio apply plugin: 'kotlin-android' android { ... sourceSets { main.java.srcDirs += 'src/main/kotlin' } ... } dependencies { ... compile "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version" ... } buildscript { ext.kotlin_version = '1.0.1-2' repositories { mavenCentral() } dependencies { classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version" } }
14. Referências Jake Wharton https://plus.google.com/+JakeWharton/posts/WSCoqkJ5MBj Kotlin lang docs reference https://kotlinlang.org/docs/reference Antonio Leiva Blog http://antonioleiva.com/kotlin/ Comece agora a brincar com kotlin http://try.kotlinlang.org/