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Delegates

object Delegates

Standard property delegates.

Functions

notNull

fun <T : Any> notNull(): ReadWriteProperty<Any?, T>

Returns a property delegate for a read/write property with a non-null value that is initialized not during object construction time but at a later time. Trying to read the property before the initial value has been assigned results in an exception.

observable

fun <T> observable(
    initialValue: T, 
    onChange: (property: KProperty<*>, oldValue: T, newValue: T) -> Unit
): ReadWriteProperty<Any?, T>

Returns a property delegate for a read/write property that calls a specified callback function when changed.

vetoable

fun <T> vetoable(
    initialValue: T, 
    onChange: (property: KProperty<*>, oldValue: T, newValue: T) -> Boolean
): ReadWriteProperty<Any?, T>

Returns a property delegate for a read/write property that calls a specified callback function when changed, allowing the callback to veto the modification.

Inherited Functions

equals

open operator fun equals(other: Any?): Boolean

Indicates whether some other object is "equal to" this one. Implementations must fulfil the following requirements:

hashCode

open fun hashCode(): Int

Returns a hash code value for the object. The general contract of hashCode is:

toString

open fun toString(): String

Returns a string representation of the object.

© 2010–2018 JetBrains s.r.o.
Licensed under the Apache License, Version 2.0.
https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.properties/-delegates/index.html