SwiftUI insertion transion is not working when view added - swiftui

Question

I'm trying SwiftUI tutorial in apple developer page. now I'm following transition tutorial but my transition is not working when the view added.
here my code.
VStack(alignment: .leading) {
HStack() {
// title
Text(titleText)
.font(.headline)
.padding()
Spacer()
// button
Button(action: {
withAnimation {
self.showDetail.toggle()
}
}) {
Image(systemName: "chevron.right.circle")
.imageScale(.large)
.rotationEffect(.degrees(showDetail ? 90 : 0))
.padding()
}
}
// detail
if showDetail {
Text(contentText)
.transition(.slide)
.padding()
}
}
I think the Text that has contentText, should appear with slide transition but when I press the Button, it just pop up. but when I press button again it disappear with transition. so removal transition is work.
How can I fix this?

Answer 1

After some test I found some solution.
solution 1:
It is just bug of XCode canvas.
It works in the simulator or on a real machine.
solution 2. (if you really want to do in canvas)
Button (action : {
withAnimation(.easeInOut) { // add animation manually
self.showDetail.toggle()
}
}) {
// label Image no change
}
if showDetail {
Text(contentText)
.transition(.slide)
.animation(.easeInOut) // match with withAnimation
}

Answer 2

Although I haven't done the tutorial you are talking about but I think it works pretty fine using the .move transition instead of the .slide transition.
Here's my code for the detail part (the rest is unchanged). I hope my answer can help you
if showDetail {
Text(contentText)
.transition(.move(edge: .leading))
.padding()
}