[Feature Request] Disable animations globally

[xavierLowmiller]

Description

In our app, we do a lot of snapshot testing.
To keep these deterministic, we disable the Lottie animations by hand, which works 👍.

It would be much easier, though, if Lottie looked at UIView.areAnimationsEnabled so that animations could be enabled or disabled globally.

If you're interested, I can try and submit a pull request.

Check these before submitting:

• The issue doesn't involve an Unsupported Feature
• This issue isn't related to another open issue

This issue is a:

• Non-Crashing Bug (Visual or otherwise)
• Crashing Bug
• Feature Request
• Regression (Something that once worked, but doesn't work anymore)

Which Version of Lottie are you using?

Lottie 3.0

What Platform are you on?

• MacOS
• iOS

What Language are you in?

• Swift
• Objective-C

[kwstasna]

@xavierLowmiller how do you disable the animations while you take the snapshots?

[xavierLowmiller]

Just set UIView.setAnimationsEnabled(false)

[kwstasna]

@xavierLowmiller ah ok! Do you know how to display only the final frame so that the test don’t have to wait for the animation to finish ?

[xavierLowmiller]

Oh sorry, you mean how we disable the Lottie animations?

I can't take a look how we exactly did it because I've switched jobs and don't have access to the code base.

As far as I remember, we just called stop() on the view, and maybe set the animationProgress to some deterministic value.

[amja]

Was there any reason this wasn't taken up? Looks like Lottie Android has incorporated similar behaviour. Would be super useful for many people I am sure!

[calda]

We added support for reduced motion in #2110

[calda]

Ah, we don't handle UIView.areAnimationsEnabled though.

[amja]

I'm glad reduced motion is supported as that's a much more important use case but yes, would be wonderful if we could do something similar for UIView.areAnimationsEnabled.

[calda]

Anyone interested in working on a PR? Happy to review one.

[amja]

I could definitely do it but I had a moment of doubt and would like to get some consensus. Though it's not clearly defined in the docs, it seems like UIView.setAnimationsEnabled(:)'s purpose is mainly to disable UIKit lifecycle animation like view controller presentation etc. It doesn't, for example, stop a UIActivityIndicatorView from spinning if you call the startAnimating() method on it.

Though it definitely would be convenient to have an ability to globally disable Lottie animation, I worry that hooking into this system might not be totally appropriate.

[calda]

We could use an approach similar to #2110, where it uses UIAccessibility.isReduceMotionEnabled by default but in a way that lets the consumer override this with some other configuration if they want.