Is Kotlin Ready for Android

Transcript

1. Is Kotlin Ready for Android
   Peter-John Welcome
   @pjapplez
   

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2. Google announced Kotlin will be an official language for Android
   

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3. Kotlin
   Was born in 2011 by JetBrains Team
   ● Modern
   ● Expressive
   ● Magical
   ● Powerful
   ● Concise
   ● Extensible
   https://en.wikipedia.org/wiki/Kotlin_(programming_language)
   

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4. Kotlin
   ● Small runtime
   ● Statically typed language
   ● Modern language
   ● Runs on JVM and converts to Java byte code
   ● Reduces errors and boiler plate code
   ● Composition over inheritance
   

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5. Why Kotlin over Java
   ● We still on Java 6.5 in Android
   ● Java Code is error Prone with all its anonymous inner classes
   ● Java Language Restriction ( lambdas , Default Interfaces … etc )
   ● Java code is very verbose.
   

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6. What Java doesn’t have
   ● High-order functions
   ● Properties
   ● Extension functions
   ● Static null checks
   ● Auto casting/Smart casting
   ● Default parameters
   ● String interpolation
   ● Pattern matching
   ● Inline functions
   ● Infix methods
   

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7. Android’s Root Problem
   https://image.slidesharecdn.com/droidcon-bugsense-130408170720-phpapp01/95/droid-con-bugsense-16-638.jpg?cb=1365440918
   

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8. "I call it my billion-dollar mistake... [which] has led to innumerable errors,
   vulnerabilities, and system crashes, which have probably caused a billion dollars of
   pain and damage in the last forty years." — Sir Charles Antony Richard Hoare
   Nullability
   https://blog.valbonne-consulting.com/2014/11/26/tony-hoare-invention-of-the-null-reference-a-billion-dollar-mistake/
   

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9. var a: String = "foo"
   a = null //Compilation error
   var b: String? = "bar"
   b = null //ok
   Nullability
   

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10. val user = User() // there's no 'new' keyword in Kotlin
    user.name = "PJ"
    Properties
    

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11. inline fun SharedPreferences.edit(action: SharedPreferences.Editor() -> Unit) {
    val editor = SharedPreferences.Editor()
    editor.action()
    editor.apply()
    }
    getSharedPreferences(MODE_PRIVATE).edit {
    putString("username", username)
    }
    Extension Functions for Android
    

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12. Anko
    ● Anko Commons: a lightweight library full of helpers for intents, dialogs,
    logging and so on;
    ● Anko Layouts: a fast and type-safe way to write dynamic Android layouts;
    ● Anko SQLite: a query DSL and parser collection for Android SQLite;
    ● Anko Coroutines: utilities based on the kotlinx.coroutines library.
    

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13. Should we be on the Kotlin Train?
    Most Definitely !!!!
    

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14. Kotlin advantages
    ● Less crashes
    ● Easier to develop in
    ● Encourages functional paradigm
    ● 100 % Interoperable with Java ( Can use within existing code base.)
    

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15. Kotlin Community
    

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16. Resources
    ● https://blog.mindorks.com/a-complete-guide-to-learn-kotlin-for-android-development-b1e5d23
    cc2d8
    ● https://leanpub.com/kotlin-for-android-developers
    ● https://developer.android.com/kotlin/index.html
    ● https://kotlinlang.org/docs/tutorials/kotlin-android.html
    

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17. Thanks!
    Contact me:
    google.com/u/0/+PeterJohnWelcome
    @pjapplez
    pjwelcome@gmail.com
    Peter-johnwelcome.co.za
    https://github.com/pjwelcome
    

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