Too Long; Didn't Read
In Flutter we need to find a way to manage all 3 phases (Loading, Success, Error) within the app life-cycle in an easy-to-test and easy-to-use way. This article uses Dart streams and RxDart library to build the screen state. The code is based on a functional programming style, meaning we can have a chain of transformation functions applied to a stream. This function acts as a filter. It calls its body each time a value is emitted by the stream. It checks if it is an even number and returns the element.