Wrong animation at start of animation

[creactit]

Description

Hi,
I have added skeleton on collectionview cell.

At start of animation I have two problems:

1. On my cell the labels and button are centered but at start of skeleton I see the entering animation from left
2. While step 1 is completed the skeleton animation it's wrong (forever top/down animation).

What type of issue is this? (place an x in one of the [ ])

• bug

Requirements (place an x in each of the [ ])

• [ X] I've read and understood the Contributing guidelines and have done my best effort to follow them.
• [ X] I've read and agree to the Code of Conduct.
• [ X I've searched for any related issues and avoided creating a duplicate issue.

Bug Report

Filling out the following details about bugs will help us solve your issue sooner.

SkeletonView Environment:

SkeletonView version: 1.30.4
Xcode version: 14.2
Swift version: 5.7.2

Steps to reproduce:

Please replace this with the steps to reproduce the behavior.

1. Create collectionview cell with centered label
2. Apply skeleton at cell

Expected result:

Don't see animation from left to right
Don't see incorrect animation

[Serg-Pogrebnyak]

same on my end, here a video with a bug
cell created in a xib

skeleton.bug.mp4

[creactit]

Yes the problem it's the same of top left cell

[Serg-Pogrebnyak]

and also in the video, you can see when the animation starts from the default gradient (from top to bottom) and then switches on the animation which was sent as a parameter (left to right)

[Serg-Pogrebnyak]

So, looks like I found the problem and fixed it on my end, here are my solution and description of why it's happening:
All skeletons it's a layers, and they build on the fly recursively, as you know at some time application UI is not ready and as a result, skeletons layers has incorrect frame and bounds. In the library, they make swizzling of the UIView.layoutSubviews method, so when the system calls layoutSubviews it changes in the runtime on their, and at this time skeletons update their frame and bounds. But in viewWillAppear, we already have the final UI, but layoutSubviews will be called slightly late, that's why you will see the old position and animated change of the skeleton view.

To avoid this I made two things:

1. In the func startTransition(transitionBlock: @escaping () -> Void) function, I added layoutIfNeeded() to build the finish UI and avoid animation change;
   
2. In
   func recursiveShowSkeleton (skeletonConfig config: SkeletonConfig, root: UIView? = nil)
   and
   func recursiveUpdateSkeleton (skeletonConfig config: SkeletonConfig, root: UIView? = nil)
   functions I added the layoutSkeletonIfNeeded() function, this force call will update the frame and bounds set all skeletons in the correct position at THIS moment, and does not wait when the system calls layoutSubviews(), as a result when the controller will be presented, you will see correct position of your skeletons.