Can't change alpha of subview when cell is focused - swift

Question

I have a simple imageView added to a custom UICollectionViewCell. I initialize it when i declare it:
let likeIcon = UIImageView()
And then I set properties in my class' initializer:
likeIcon.image = UIImage(named: "heart_empty")!
likeIcon.alpha = 0.0
addSubview(likeIcon)
Nothing too crazy. I want the imageView to be hidden initially but then visible when the cell is clicked.
I have a simple method that I call when the cell is selected (it's not animated yet):
func toggleLikeButtonAnimated() {
likeIcon.frame = likeIconFrame()
likeIcon.alpha = 1.0
}
But the icon doesn't show.
If I comment out the initial likeIcon.alpha = 0.0 then the icon is visible selected or unselected, so it's there
toggleLikeButtonAnimated is definitely called
The frame is the correct frame
The only thing I can think of, since this is really strange, is that something with the focus engine is interfering with the alpha changing.
I have this code in the cell right now:
// MARK: -- Focus
override func didUpdateFocusInContext(context: UIFocusUpdateContext, withAnimationCoordinator coordinator: UIFocusAnimationCoordinator) {
super.didUpdateFocusInContext(context, withAnimationCoordinator: coordinator)
coordinator.addCoordinatedAnimations({ () -> Void in
if self.focused {
self.focusItem()
} else {
self.unfocusItem()
}
}) { () -> Void in
}
}
func focusItem() {
self.overlay.alpha = 0.0
}
func unfocusItem() {
self.overlay.alpha = 0.6
}
The overlay is below the icon so it shouldn't interfere with it's visibility. So I tried this:
// MARK: -- Focus
override func didUpdateFocusInContext(context: UIFocusUpdateContext, withAnimationCoordinator coordinator: UIFocusAnimationCoordinator) {
super.didUpdateFocusInContext(context, withAnimationCoordinator: coordinator)
coordinator.addCoordinatedAnimations({ () -> Void in
if self.focused {
self.focusItem()
} else {
self.unfocusItem()
}
}) { () -> Void in
}
}
func focusItem() {
self.overlay.alpha = 0.0
self.likeIcon.alpha = 1.0
}
func unfocusItem() {
self.overlay.alpha = 0.6
self.likeIcon.alpha = 0.0
}
The likeIcon animates in when the cell is focused and out when unfocused. But this is not what I want, and it seems like the animation of the focus engine is preventing my alpha change when selected.
Any ideas on how to fix?

Answer 1

According your description，you want the imageView to be hidden initially but then visible when the UICollectionViewCell is clicked, but it is did't work. When you set UICollectionViewDelegate，you must be call reloadData function，just like UITableView.Maybe you can try use this when you click cell.Solve you problem yet.