I was hoping Interpolate could make my life a lot easier with my current task. I have 3 screens inside a UIScrollView So three pages. Each pages is a specific color. I need to animate the background color as I scroll. It seems that interpolate only allows two vectors. To and From I need to define a third: Mid. So if progress was at 0 then the screen would be blue. progress was set to 0.5 the screen would be red progress set to 1 would be green.

Is this possible with the current version?

@marmelroy I tried this all day yesterday with the JWGCircleCounter) and CircleProgressView

Steps to Reproduce

• Instantiate a CircleProgressView or any other animatable circle view to the top right of your view.

• On tap, interpolate the object down to the center bottom of the screen.

• The object on top right will be perfectly nice and crisp.

• When it gets to the bottom, it will be blury and fuzzy

class ViewController: UIViewController {
    
    var circle: CircleProgressView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        self.addRecordButton()
    }
    
    func addRecordButton() {
        self.circle = CircleProgressView(x: self.view.size.width - 56, y: 29, w: 30, h: 30)
        self.circle.trackBackgroundColor = .blue
        self.circle.trackBorderWidth = 3
        self.circle.backgroundColor = .clear
        self.circle.layer.cornerRadius = self.circle.size.width / 2
        
        let tap = UITapGestureRecognizer(target: self, action: #selector(self.tap))
        self.circle.addGestureRecognizer(tap)
        
        self.view.addSubview(circle)
    }
    
    func tap() {
        self.interpolate()
    }
    
    func interpolate() {
        let newframe = CGRect(x: self.view.centerX - 37.5, y: self.view.size.height - 100, w: 75, h: 75)
        let interpolate = Interpolate(from: self.circle.frame, to: newframe) { (newframe) in
            self.circle.frame = newframe
        }
        interpolate.animate(duration: 5)
    }
}

Hi ! :) I have the problem that my code below is not printing any values. I'm using Xcode 8 and Swift 3.

let i = Interpolate(from: 100.0, to: 3.0, apply: { n in print(n) })
        i.animate(duration: 3.0)

For some reason, the following doesn't work at all:

let i = Interpolate(from: 100.0, to: 3.0, apply: { n in print(n) })
i.animate(duration: 3.0)

but this does:

i = Interpolate(from: CGFloat(100.0), to: CGFloat(3.0), apply: { n in print(n) })
i.animate(duration: 3.0)

I'm using version 0.2.0 with Swift 2.3. I can't figure this out without getting pretty deep into the code but the init() seems to set up the instance variables identically. I'm lost, but I'd love to know what the problem is — hopefully on my end.

Cocoapods supports setting the swift version directly using the swift_version configuration parameter.

I was working on a project that used Interpolate but I was getting weird compiler errors about code that was recently updated for Swift 4.2. It turns out the xcconfig for the swift version wasn't getting properly set on the Pod target. Once I changed that setting to use swift_version the target built without errors.

@marmelroy eg. SpringInterpolation(damping: 30.0, velocity: 0.0, mass: 1.0, stiffness: 100.0) Hey, I find that using Spring Interpolations, my animations do not finish at their destination even though progress = 100%. Instead they are always near completion.

Why is that?

I use this project in an App extension and always got the warning that this library isn't App extension safe. Since the code doesn't reference any non App Extension safe APIs, it is safe to enable this.

I also updated the project settings to the recommended settings in Xcode 8.1

Is there also a way to animate constraints with Interpolate? Would be nice to have an example for that.

I assume it's just calling layoutIfNeeded() after assigning the change inside Interpolate closure?

The example app has basically

    func progress(scrollProgress:CGFloat) {
        let groundProgress = scrollProgress * 1.5
        backgroundColorChange?.progress = scrollProgress
        logoAlpha?.progress = scrollProgress
        groundPosition?.progress = groundProgress
        bojackPosition?.progress = groundProgress
        bojackShadowPosition?.progress = max(groundProgress - 1, 0)
    }

So I can set the progress with procress(0) and procress(1) for the whole interpolations - but how I can animate that? Running animate on all interpolations feels wrong. Something along the lines of this would be great:

progress(0)
UIView.animate(...) {
  progress(1)
}

• Updates the Sample Podfile to work with CocoaPods 1.0.
• Adds the missing files to git, that are create after a pod install. This makes a pod install redundant and one can try the Sample right away after the download.

Use generic initializer to create Interpolate objects. This way, there is no need to typecast inside the apply block, so the code becomes cleaner.

let colorChange = Interpolate(from: UIColor.whiteColor(), to: UIColor.redColor(), apply: { [weak self] (color) in
    self?.view.backgroundColor = color
})

Also, this guarantees that the type of from parameter is the same as the type of to, so there is no way to write code like this:

let change = Interpolate(from: UIColor.whiteColor(), to: 10.0, apply: { [weak self] (result) in
    // This will cause a fatal error in calculateDiff
})