Atternatt

data class DataCaptionInfo(private val context: Context) {

    var name: String by Delegate.prefParam(context,"NAME", "")

    var lastName: String by Delegate.prefParam(context, "LAST_NAME", "")

    var email : String by Delegate.prefParam(context, "EMAIL", "")

    var referalCode: String by Delegate.prefParam(context, "REFERAL_ID", "")

Atternatt

sum4(4) //return 8
div2(4) //return 2

listOf(3,4,6,8,10)
        .map(sum4)
        .map(div2)
//[3, 4, 5, 6, 7]

fun hello(name: String, textDecorator: () -> String): String {
    return "hello $name ${textDecorator()}"

Atternatt

fun <T : Comparable<T>> List<T>.sort() {
  Collections.sort(this)
}

list.sort();
val index = list.binarySearch(x);

val 

Atternatt

bundle?.let { intent.putExtras(it) } //si el bundle no es null, lo añadimos como extra al intent

//crear un animationSet al estilo builder
val animationSet = AnimatorSet().apply {
        playTogether(animX, animY)
        duration = 350
        interpolator = FolioBounceInterpolator()
    }.start()

Atternatt

operator fun String.get(intRange: IntRange): String {
    return this.substring(intRange)
}

val firstSentence = "hello Marc!"
val secondSentence = "World Wide"

val mixedSentence = firstSentence[0..4] + secondSentence[0..4] 
//Hello World

Atternatt

fun twice(int: Int) = int * 2
fun trice(int: Int) = int * 3
fun getString(int: Int) = int.toString()

//el operador rangeTo es el '..' acepta un parametro de entrada y otro de salida
//si usamos mónadas para enlazarlo podemos concatenar la salida de uno con la entrada del otro
operator fun <T,R,V> ((T)->R).rangeTo(other: ((R)->V)): ((T)->V){
    return {
        other(this(it))
    }

Atternatt

inline fun <reified NewActivity : Activity> Activity.start(bundle: Bundle? = null) {
    val intent: Intent = Intent(this, NewActivity::class.java)
    bundle?.let { intent.putExtras(it) }
    this.startActivity(intent)
}

startActivity<MainActivity>()


infix fun <Value>Boolean.then(block: () -> Value) {

Atternatt

import android.databinding.Observable as DataBindingObservable

private inline fun <reified T : DataBindingObservable, R : Any?> T.observe(
        crossinline block: (T) -> R
): Observable<R> = create { subscriber ->
    object : android.databinding.Observable.OnPropertyChangedCallback() {
        override fun onPropertyChanged(observable: DataBindingObservable, id: Int) = try {
            subscriber.onNext(block(observable as T))
        } catch (e: Exception) {
            subscriber.onError(e)

Atternatt

class ByDouble(incrementer: Incrementer) : Incrementer by incrementer {

    override fun increment(number: Int): Int {
        return super.increment(number) * 2
    }
}

Atternatt

class Database(private context: Context) {
        val helper: SQLiteOpenHelper by lazy { SQLiteOpenHelper(context,...-) }
        val observableProperty: Int by Delegates.observable { thisRef , newValue , oldValue -> doSomething()}
        val vetoableProperty: Int by Delegates.vetoable { _ , newValue , oldValue -> return if (oldValue < newValue) true else false  }
}