UIStackView - hide and collapse subview with animation

Question

I'm trying to hide UIStackView's subview like this:

UIViewPropertyAnimator.runningPropertyAnimator(withDuration: 2.0, 
      delay: 0, options: [.curveEaseOut], animations: {
    self.label.isHidden = true
    self.label.alpha = 0.0
    self.stackView.layoutIfNeeded()
})

However, the label disappears instantly with using this code. I suspect this is because of setting isHidden to true, which is required for collapsing.

Is there a way how to hide and collapse UIStackView's subvew with animation? Or it might be better to not to use UIStackView at all?

Answer 1

According to Apple's documentation:

You can animate both changes to the arranged subview’s isHidden property and changes to the stack view’s properties by placing these changes inside an animation block.

I've tested the below code using iOS 12.1 Simulator and it works as expected.

UIView.animate(
    withDuration: 2.0,
    delay: 0.0,
    options: [.curveEaseOut],
    animations: {
        self.label.isHidden = true
        self.label.alpha = 0.0
})