Reputation: 51
I'm new to SwiftUI, but I have a good knowledge about Storyboard.
At the beginning I want to start with some animations, but I have a problem with one of them:
I know @State
variables, the .onAppear
event, repeating animations with the autoreverse
bool, but I don't know how to use them to become the best resolution.
I hope that someone can help me.
@State var element_appeared : Bool = false
Image(systemName: "paperplane.fill")
.resizable()
.frame(width: element_appeared ? 50 : 0, height: element_appeared ? 50 : 0)
.onAppear() {
element_appeared.toggle()
}
.animation(.easeInOut)
This is how the animation at the beginning works. I think that I have to work on the element_appeared
variable, but I really don't know how..
Upvotes: 4
Views: 3556
Reputation: 5289
Based on @nicksarno's answer, replacing use of DispatchQueue
, with a .delay()
on the second animation:
struct AnimatingPlaneView: View {
@State private var showIcon = false
@State private var animateForever = false
private var sideSize: Double { showIcon ? 50 : 0 }
var body: some View {
Image(systemName: "paperplane.fill")
.resizable()
.frame(width: sideSize, height: sideSize)
.opacity(showIcon ? 1 : 0)
.scaleEffect(animateForever ? 0.8 : 1)
.onAppear {
withAnimation(.easeInOut(duration: 1)) {
showIcon.toggle()
}
withAnimation(.easeInOut(duration: 1).repeatForever().delay(1)) {
animateForever.toggle()
}
}
}
}
Upvotes: 0
Reputation: 4245
Here's an example. I used a 2nd @State to manage the different animations.
@State var showIcon : Bool = false
@State var animateForever: Bool = false
var body: some View {
Image(systemName: "paperplane.fill")
.resizable()
.frame(width: showIcon ? 50 : 0, height: showIcon ? 50 : 0)
//.opacity(showIcon ? 1.0 : 0.0)
.scaleEffect(animateForever ? 0.8 : 1.0) // 0.8 == 40/50
.onAppear() {
withAnimation(Animation.easeInOut(duration: 1.0)) {
showIcon.toggle()
}
DispatchQueue.main.asyncAfter(deadline: .now() + 1.0) {
withAnimation(Animation.easeInOut(duration: 1.0).repeatForever()) {
animateForever.toggle()
}
}
}
}
Upvotes: 1
Reputation: 54641
You can create an enum as you animation has more than two states. Then use DispatchQueue
to delay the second animation.
Here is a demo:
enum AnimationState {
case notAppeared, appeared, animating
}
struct ContentView: View {
@State private var animationState: AnimationState = .notAppeared
private let delay: TimeInterval = 1
var body: some View {
Image(systemName: "paperplane.fill")
.resizable()
.frame(width: imageSize, height: imageSize)
.onAppear {
withAnimation(.easeInOut(duration: delay)) {
animationState = .appeared
}
DispatchQueue.main.asyncAfter(deadline: .now() + delay) {
withAnimation(Animation.easeInOut.repeatForever()) {
animationState = .animating
}
}
}
}
private var imageSize: CGFloat {
switch animationState {
case .notAppeared: return 0
case .appeared: return 50
case .animating: return 40
}
}
}
Upvotes: 4