Add an extension property to get the children of a ViewGroup as a Iterable about android-ktx

[JakeWharton]

The opposite of that is also true in asIterable()

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On Mon, Feb 5, 2018 at 8:31 PM Mozart Petter ***@***.***> wrote: IMHO it should always return a Iterable. If you need it as a sequence you could always do myView.children.asSequence(). — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#138 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAEEEQYv-zLZ80a7WZltqNEF4Wte-rD2ks5tR6tngaJpZM4R6IN6> .

[JakeWharton]

Yeah. Plus there actually are a few eager operators on Sequence like `any` which are commonly used.

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On Mon, Feb 5, 2018 at 8:46 PM Kevin Most ***@***.***> wrote: It seems equally simple, as Jake said, to convert between Iterable and Sequence. I personally like how, if you provide it as a Sequence, doing something like children.filterIsInstance<FooView>().map { it.foo() }.first() is lazily evaluated by default, without having to remember to convert it to a Sequence first. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#138 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAEEEQzf1fFsmICrtb_yOIgzV7xgU9Chks5tR673gaJpZM4R6IN6> .

[JakeWharton]

Yeah we used to have something like this until we switched to operator fun iterator(). It's a shame there isn't a structural typing such that all the existing collection extensions could apply. Is there any reason to expose a List rather than an Iterable?

[quiro91]

Honestly no, I agree that Iterable seems more appropriate. Will change the title of the issue

[kevinmost]

Any thoughts on it being a Sequence instead? This is what we implemented in our project, I'm not sure if the laziness of a sequence is more or less desirable though.

/**
 * Returns a [Sequence] that iterates through the children of this view
 */
val ViewGroup.children: Sequence<View>
    get() {
        var currentIndex = -1
        return generateSequence {
            currentIndex++
            getChildAt(currentIndex)
        }
    }

[mokkun]

IMHO it should always return a Iterable. If you need it as a sequence you could always do myView.children.asSequence().

[kevinmost]

It seems equally simple, as Jake said, to convert between Iterable and Sequence. I personally like how, if you provide it as a Sequence, doing something like children.filterIsInstance<FooView>().map { it.foo() }.first() is lazily evaluated by default, without having to remember to convert it to a Sequence first.

[JakeWharton]

Was merged.