And obviously there is a function findLast () to return the last found element.įirst(), firstOrNull(), last(), lastOrNull() and component1–5() return exact elements from the collection. There is a really simple realization inside this function: public inline fun Iterable.forEachIndexed(action: (index: Int, T) -> Unit): Unit įind() returns you the first found element. The most common operation when you work with collections is iteration through collection items for (int i = 0 i friend.id = index Let’s check all important functions that we have in the llection framework and compare it to an implementation to Java. But if we compare it to Rx, there are no subscribers, observers, etc. In this example, we will create two menu items - Share and Settings.

So the idea is that you have some stream of data, and using some functions you can receive some required state of the stream. To do this, you will create a new XML file in the res/menu directory of your project. This approach is very similar to Java 8 collections and Rx usage.

Now I am going to show you the coolest thing in Kotlin collections – the functional approach Kotlin provides on top of collections.

Software Engineer Android the two previous articles we talked about collections structure and all the possible ways to create them.

Kotlin any example