Some notes on UIView animation

UIView animation is a simple and nice way to add to your user experience. I just wanted to point out a few suggestions when using UIView animations.

Duration (speed):
If you choose to use animation to compliment some of the stuff already happening in UIKit, either at the same time or before/after, it makes a big difference how fast your animations are. Pretty much all the UIKit animations I have come across have a duration of 0.3f and so should yours. Of course, it’s doesn’t always work 100% but for the most part, 0.3f is what you should aim for. It’s quick so your user don’t wait for something to finish animating before continuing with the next input action, and it’s not too fast so that the user doesn’t have a chance to see where the object came from or what happened.

If you have an animation happening while the keyboard animates up or down, use an animationDuration of 0.3f. Same with pushing and popping the navigationController. Annotations in MKMapView also drop at a duration of 0.3f.

0.3f is the way to go.

A simple UIView animation can be added with the following code:

[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.3f];
self.segmentControl.alpha = 1.0f;
[UIView commitAnimations];

The above example is from an app I’m doing, where the segmentControl is enabled and I increase its visibility in the toolBar at the same rate as a pin drops in the map within the same screen.

When to use animation:
A few objects come with free animation (also at a duration of 0.3f, of course). For example, when adding a UIBarButton to your UINavigationBar, consider setting these with animation. If you replace a UIBarButton with another, they’ll even animate in and out nicely during the change. When adding a pin to a map, why not drop it onto the map with an animation, instead of it suddenly appearing on a map from nowhere?

Another good advice is to do animation (whether your own or with objects that include animations) to bring attention to an object. For example, if you have a pushed view, consider what you can “add” after the view has appeared through animating your objects in viewDidAppear.

Create a better UX with animation
Consider all the ways you can use UIView animation blocks in your app to enhance the user experience. It’s a great way to create a more fluid and pleasant experience for your users. A user’s inputs and actions will feel less rough and more smooth and soft to the touch. Don’t go overboard with animations. Too many will become annoying and it’s important to use animations only where appropriate.

The best advice is probably to have a look at many of the built in apps designed by Apple as well as the many free animations that a part of UIKit objects (how UIBarButtons animate in and out when you push a UIViewController stack, how a modal view appears from the bottom, etc.).