Change CollectionView position with animation but move back when first scroll - ios

Question

I want to change my collectionView position when pressing a button. I wrapped the collectionView and Button in a View and used UIView animate to make it move up. It can move up successfully, but when I am scrolling collectionView it's return back to its original position. If I tried many times, it became normal and didn't move back again.
How could i fix this issue? Thank you for any advice.
func openPreview() {
if !isPreviewOpened {
UIView.animate(withDuration: 0.3) {
self.previewView.frame.origin.y -= self.previewView.frame.height
self.previewButton.frame.origin.y -= self.previewView.frame.height
}
isPreviewOpened = true
updateUI()
}
func closePreview() {
if isPreviewOpened {
UIView.animate(withDuration: 0.3) {
self.previewView.frame.origin.y += self.previewView.frame.height
self.previewButton.frame.origin.y += self.previewView.frame.height
}
isPreviewOpened = false
updateUI()
}
}

Answer 1

After asking others, provide my solution to this question, hope it can help someone in the future.
This issue was happened because that the frame I changed conflicting with the auto layout I set earlier in storyboard. According to the document, I have to set translatesAutoresizingMaskIntoConstraints to true to track the frames.
By default, the autoresizing mask on a view gives rise to constraints that fully determine
the view's position. This allows the auto layout system to track the frames of views whose
layout is controlled manually (through -setFrame:, for example).
When you elect to position the view using auto layout by adding your own constraints,
you must set this property to NO. IB will do this for you.
So this is the answer.
func openPreview() {
if !isPreviewOpened {
previewView.translatesAutoresizingMaskIntoConstraints = true
UIView.animate(withDuration: 0.3) {
self.previewView.frame.origin.y = self.view.bounds.maxY - self.previewView.frame.height
self.previewButton.frame.origin.y = self.view.bounds.maxY - self.previewView.frame.height - self.previewButton.frame.height
}
}
}