Press enter or click to view image in full size

Introduction

UIStackView is one of the most important and powerful UIKit components introduced in iOS 9. It is so powerful and elegant that it really speeds up a lot of us pushing to drop support for iOS 8.

For people that work with Auto Layout a lot, you will know that it is not particularly fun and easy to create NSLayoutConstraints. Since each view on a 2D screen has four degrees of freedom, it means that, in general, we would have to create at least four constraints for each view.

So, back to the introduction of stack view, was it that much of an innovation?

Not really, since Android’s equivalent LinearLayout was introduced at the beginning of the universe (a.k.a. API level 1). Not sure why it took Apple eight years to introduce this component.

But anyway, we are all very happy that it is finally available.

Even though UIStackView simplified the view layout a lot by reducing the number of constraints that we would have to implement otherwise, it can still get pretty complicated and somewhat confusing.