Can you control the progress of a SwiftUI animation - swift

Question

Is it possible to control the progress of withAnimation
Ideal API would look something like this
withAnimation(progress: percentDragged) { showSecondView.toggle() }
Here's a full code example of the above line in context.
The goal is to smoothly slide between different app states with a user controlled gesture.
struct ContentView: View {
#State var showSecondView = false
var body: some View {
VStack {
ZStack {
if !showSecondView {
Text("First view")
.padding()
.background(Color.blue)
.transition(.slide)
} else {
Text("Second view")
.padding()
.background(Color.red)
.transition(.slide)
}
}
}
.gesture(
DragGesture()
.onChanged { value in
let percentDragged = value.translation.width / UIScreen.main.bounds.width
// Here I want to gradually slide (interpolate) between the two states
// Ideal API would look like this:
withAnimation(progress: percentDragged) { showSecondView.toggle() }
}
)
}
}
Yes.. I know I can trigger an animation whenever I want (like this). but that's not what I'm looking for! I want to control the progress
if percentDragged > 0.5 {
withAnimation { showSecondView.toggle() }
}
Yes.. I also know I could manually store a #State var offset: Double and control my own slide.
This just gets nasty when my app state is tied to tons of different visual changes. Views appearing/disappearing, alignments shifting, etc.