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#android
  • j

    jw

    01/21/2016, 4:00 AM
    the challenging part is streaming the response to multiple consumers since ResponesBody is a one-shot read
  • d

    debug

    01/21/2016, 4:08 AM
    I was thinking of registering observers in a list and use the retrofit callback to notify those observers, but the problem was on how to map the request types.
  • d

    debug

    01/21/2016, 4:27 AM
    The reason I'm attempting to do this is because I want to abstract away the retrofit API service, a queue was something that first came into my mind.
  • d

    debug

    01/21/2016, 4:29 AM
    Sort of a data source type thing, the one requesting won't know the actual source of data. Only assumption to be made is that the request could be asynchronous, hence the requestor will register its observer.
  • j

    juancho

    01/21/2016, 10:01 PM
    Pasted image at 2016_01_21 07_00 PM.png
  • e

    eric

    01/21/2016, 10:06 PM
    You have a 
    kotlin.List
    , and you need a 
    java.util.ArrayList
    .
  • j

    juancho

    01/21/2016, 10:08 PM
    and how can I convert this kotlin list into a java arraylist? @eric
  • e

    eric

    01/21/2016, 10:12 PM
    the List is just an interface type. What is the runtime type?
  • d

    damian

    01/21/2016, 10:22 PM
    If it's not an 
    ArrayList
    (or you don't know and don't mind making a copy), you can always use 
    .toArrayList()
  • j

    juancho

    01/21/2016, 11:58 PM
    Thanks @damian ! it works simple smile 👍
    K 1
  • k

    kirillrakhman

    01/22/2016, 10:48 AM
    I have an interesting issue. I declared the following extension methods to use a 
    TextView
    as delegate for a 
    CharSequence
    property:
    Copy code
    operator fun TextView.getValue(thisRef: Any, property: KProperty<*>) = text
operator fun TextView.setValue(thisRef: Any, property: KProperty<*>, value: CharSequence) {
    text = value
}
    Using the Android Extensions, I thought the following should work:
    Copy code
    import kotlinx.android.synthetic.main....

var foo: CharSequence by editTextFoo
    However, as soon as I call the property, I get a
    Copy code
    java.lang.IllegalArgumentException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull, parameter $receiver
	at package.name.DelegateUtilsKt.getValue(DelegateUtils.kt:65532)
    the culprit seems to be that when the property is initialized, the view isn't actually inflated so the property is delegated to 
    null
    . Any ideas how I could get around this without declaring an additional delegate class?
  • k

    kirillrakhman

    01/22/2016, 10:49 AM
    Obviously I could write the property getters and setters by hand, but that's no fun
  • y

    yoavst

    01/22/2016, 10:53 AM
    You should use 
    lazy
  • k

    kirillrakhman

    01/22/2016, 10:56 AM
    you mean delegate to 
    Lazy<TextView>
    ?
  • k

    kirillrakhman

    01/22/2016, 10:59 AM
    I was kinda hoping to avoid alocating any additional objects
  • y

    yoavst

    01/22/2016, 11:00 AM
    But since every view is only available after onCreate, you have to.
  • k

    kirillrakhman

    01/22/2016, 11:00 AM
    Copy code
    var foo: CharSequence
        get() = editTextFoo.text
        set(value) {
            editTextFoo.text = value
        }
    works but is not as terse
  • y

    yoavst

    01/22/2016, 11:00 AM
    You can make delegation object from this, but it is extra allocation.
  • k

    kirillrakhman

    01/22/2016, 11:00 AM
    execatly
  • k

    kirillrakhman

    01/22/2016, 11:01 AM
    the beauty of my initial idea was that I already have the view object from the android extensions and I only write the extension methods once
  • y

    yoavst

    01/22/2016, 11:02 AM
    Yea, it doesn't work 😞
  • y

    yoavst

    01/22/2016, 11:03 AM
    Copy code
    val TextView.delegation: Lazy<CharSequence>
        get() = lazy { text }

var foo by editTextFoo.delegation
  • k

    kirillrakhman

    01/22/2016, 11:03 AM
    this won't update the text
  • k

    kirillrakhman

    01/22/2016, 11:04 AM
    when it's changed I mean
  • y

    yoavst

    01/22/2016, 11:04 AM
    Oh, because lazy is read only.
  • y

    yoavst

    01/22/2016, 11:05 AM
  • k

    kirillrakhman

    01/22/2016, 11:05 AM
    what if it's updated externaly
  • k

    kirillrakhman

    01/22/2016, 11:05 AM
    because it's an edittext
  • y

    yoavst

    01/22/2016, 11:06 AM
    So it is better to create a new 
    ReadWriteProperty
    object that is equivalent to your long code.
  • k

    kirillrakhman

    01/22/2016, 11:07 AM
    Copy code
    class TextDelegate(private val id: Int) : ReadWriteProperty<View,CharSequence> {
    override fun getValue(thisRef: View, property: KProperty<*>) = (thisRef.findViewById(id) as TextView).text

    override fun setValue(thisRef: View, property: KProperty<*>, value: CharSequence) {
        (thisRef.findViewById(id) as TextView).text = value
    }
}

val foo by TextDelegate(R.id.editTextFoo)
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