How to Animate Opacity Using Swift

Make a simple fade in animation in Swift?

The problem is that you're trying start the animation too early in the view controller's lifecycle. In viewDidLoad, the view has just been created, and hasn't yet been added to the view hierarchy, so attempting to animate one of its subviews at this point produces bad results.

What you really should be doing is continuing to set the alpha of the view in viewDidLoad (or where you create your views), and then waiting for the viewDidAppear: method to be called. At this point, you can start your animations without any issue.

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)

    UIView.animate(withDuration: 1.5) {
        self.myFirstLabel.alpha = 1.0
        self.myFirstButton.alpha = 1.0
        self.mySecondButton.alpha = 1.0
    }
}

Swift - How does one animate (pulse between opacity 0 and 1) a NSImage in the menu bar?

Based on @Walt 's answer, I could figure out the macOS equivalent:

    func animateMenubarIcon() {
        NSAnimationContext.runAnimationGroup { context in
            context.duration = 1
            self.statusBarItem?.button?.animator().alphaValue = 0
        } completionHandler: {
            NSAnimationContext.runAnimationGroup { context in
                context.duration = 1
                self.statusBarItem?.button?.animator().alphaValue = 1
            } completionHandler: {
                self.animateMenubarIcon()
            }
        }
    }

This will animate the button on a loop

How do you do successive animations?

So I wasn't able to incorporate the label into the keyframe animation so I just set a delay to the bale changing and it took a little tweaking but here is what I came up with

//CHANGE LABEL ON TIMER
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 13.5) 
{ [self] in
self.labelNegBeliefFinal.text = self.posBeliefLabelGlowerText
}
               
            
        
        
        
        
        
        

Here is the glow loop and size loop as before, unrelated to the tween

//AniamtionGlowLOOP
       
UIView.animate(withDuration: 6, delay: 0, options: [.autoreverse, .repeat], 
animations: { self.labelNegBeliefFinal.layer.shadowOpacity = 5.0 })

        
        
//AnimationBreathSizeLOOP
UIView.animate(withDuration: 6, delay: 0, options: [.autoreverse, .repeat], 
animations: { self.labelNegBeliefFinal.transform = CGAffineTransform(scaleX: 
1.3, y: 1.3) })
        
// }

Here is the tween code I came up with thanks to Matt for the point in the right direction. Had no idea you could tween in SwiftUI. One thing that threw me off is that if the duration is 30sec, relative duration being set to 0.5 is equal to 15 seconds as it's 0.5 of 30 seconds. Some of my tweens didn't seem to work because I didn't realize that.

UIView.animateKeyframes(withDuration: 30.0,
                                delay: 0,
                                options: [ ],
                                animations: {

                                
                                    UIView.addKeyframe(withRelativeStartTime: 
0,
                   relativeDuration: 0.5,
                   animations: { self.labelNegBeliefFinal.alpha = 0 })
                                    
                                    
                                    UIView.addKeyframe(withRelativeStartTime: 
0.5,
                   relativeDuration: 0.5,
                   animations: { self.labelNegBeliefFinal.alpha = 1 })
                                    

        },
                                completion: nil)
    
        
    

    }

}

Glow style I got from a different post

//GLOW
extension UILabel {
func UILableTextShadow1(color: UIColor){
textColor = UIColor.systemTeal
layer.shadowColor = UIColor.systemTeal.cgColor
layer.masksToBounds = false
layer.shadowOffset = .zero
layer.shouldRasterize = true
layer.rasterizationScale = UIScreen.main.scale
layer.shadowRadius = 5.0
layer.shadowOpacity = 00.7
    }

}

SwiftUI Text animation on opacity does not work

If you want to animate on opacity you need to change opacity value on your text element.

code example:

@State private var textValue: String = "Sample Data"
@State private var opacity: Double = 1
    var body: some View {
        VStack{
            Text("\(textValue)")
                .opacity(opacity)
            Button("Next") {
                withAnimation(.easeInOut(duration: 0.5), {
                    self.opacity = 0
                })
                self.textValue = "uuuuuuuuuuuuuuu"
                withAnimation(.easeInOut(duration: 1), {
                    self.opacity = 1
                })
            }
        }
    }

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