How to animate images in SwiftUI, to play a frame animation - ios

Question

I want to animate images in SwiftUI's Image view
First, I tried creating some variables and a function to toggle the Image("imageVariable"). It changes but there is no animation even tried the withAnimation { } method
Secondly, I tried to use a UIKit view. Here, the animation works but I can't apply the resizable() modifier or a set a fixed frame
var images: [UIImage]! = [UIImage(named: "pushup001")!, UIImage(named: "pushup002")!]
let animatedImage = UIImage.animatedImage(with: images, duration: 0.5)
struct workoutAnimation: UIViewRepresentable {
func makeUIView(context: Self.Context) -> UIImageView {
return UIImageView(image: animatedImage)
}
func updateUIView(_ uiView: UIImageView, context: UIViewRepresentableContext<workoutAnimation>) {
}
}
struct WorkoutView: View {
var body: some View {
VStack {
workoutAnimation().aspectRatio(contentMode: .fit)
}
}
}
In method 1 I can change the image but not animate, while, in method 2 I can animate but not control it's size

Answer 1

I solved this using UIViewRepresentable protocol. Here I returned a UIView with the ImageView as it's subview. This gave me more control over the child's size, etc.
import SwiftUI
var images : [UIImage]! = [UIImage(named: "pushup001")!, UIImage(named: "pushup002")!]
let animatedImage = UIImage.animatedImage(with: images, duration: 0.5)
struct workoutAnimation: UIViewRepresentable {
func makeUIView(context: Self.Context) -> UIView {
let someView = UIView(frame: CGRect(x: 0, y: 0, width: 400, height: 400))
let someImage = UIImageView(frame: CGRect(x: 20, y: 100, width: 360, height: 180))
someImage.clipsToBounds = true
someImage.layer.cornerRadius = 20
someImage.autoresizesSubviews = true
someImage.contentMode = UIView.ContentMode.scaleAspectFill
someImage.image = animatedImage
someView.addSubview(someImage)
return someView
}
func updateUIView(_ uiView: UIView, context: UIViewRepresentableContext<workoutAnimation>) {
}
}
struct WorkoutView: View {
var body: some View {
VStack (alignment: HorizontalAlignment.center, spacing: 10) {
workoutAnimation()
Text("zzzz")
}
}
}

Answer 2

If you want a robust and cross-platform SwiftUI implementation for animated images, like GIF/APNG/WebP, I recommend using SDWebImageSwiftUI. This framework is based on exist success image loading framework SDWebImage and provides a SwiftUI binding.
To play the animation, use AnimatedImage view.
var body: some View {
Group {
// Network
AnimatedImage(url: URL(string: "https://raw.githubusercontent.com/liyong03/YLGIFImage/master/YLGIFImageDemo/YLGIFImageDemo/joy.gif"))
.onFailure(perform: { (error) in
// Error
})
}
}

Answer 3

in model :
var publisher : Timer?
#Published var index = 0
func startTimer() {
index = 0
publisher = Timer.scheduledTimer(withTimeInterval: 0.1, repeats: true, block: {_ in
if self.index < count/*count of frames*/{
self.index += 1
}
else if let timer = self.publisher {
timer.invalidate()
self.publisher = nil
}
})
}
}
in view :
struct MyAnimationView : View {
let width : CGFloat
let images = (0...60).map { UIImage(named: "tile\($0)")! }
#StateObject var viewmodel : MyViewModel
var body: some View {
Image(uiImage: images[viewmodel.index])
.resizable()
.frame(width: width, height: width, alignment: .center)
}
}

Answer 4

I have created an image animation class that can be easily reused
import SwiftUI
struct ImageAnimated: UIViewRepresentable {
let imageSize: CGSize
let imageNames: [String]
let duration: Double = 0.5
func makeUIView(context: Self.Context) -> UIView {
let containerView = UIView(frame: CGRect(x: 0, y: 0
, width: imageSize.width, height: imageSize.height))
let animationImageView = UIImageView(frame: CGRect(x: 0, y: 0, width: imageSize.width, height: imageSize.height))
animationImageView.clipsToBounds = true
animationImageView.layer.cornerRadius = 5
animationImageView.autoresizesSubviews = true
animationImageView.contentMode = UIView.ContentMode.scaleAspectFill
var images = [UIImage]()
imageNames.forEach { imageName in
if let img = UIImage(named: imageName) {
images.append(img)
}
}
animationImageView.image = UIImage.animatedImage(with: images, duration: duration)
containerView.addSubview(animationImageView)
return containerView
}
func updateUIView(_ uiView: UIView, context: UIViewRepresentableContext<ImageAnimated>) {
}
}
The way to use it:
ImageAnimated(imageSize: CGSize(width: size, height: size), imageNames: ["loading1","loading2","loading3","loading4"], duration: 0.3)
.frame(width: size, height: size, alignment: .center)