Map view jumps to old fraction when scrolled

[stevengharris]

I'm evaluating this library and I found a problem when trying to put a Map (SwiftUI) into the Top view on a VSplit. I've reproduced it by adding a Map to the Demo sample simpleAdjustable Code below. Once I move the map (or zoom) the Split is resized back to an original position instead of retaining where the User left it. Is there a known workaround to resolve this? Video below.

case .simpleAdjustable:
                Split(
                    primary: {
                        Map(coordinateRegion: $region, annotationItems: annotations) {
                            MapPin(coordinate: $0.coordinate)
                        }
                    },
                    secondary: { Color.red }
                )
                .styling(color: .yellow)
                .layout(demo.holders[0].layout)
                .hide(demo.holders[0].hide)

Simulator.Screen.Recording.-.iPhone.14.Pro.-.2024-12-16.at.12.41.17.mp4

Other supporting code:

@State var region: MKCoordinateRegion = MKCoordinateRegion(center: CLLocationCoordinate2D(latitude: 37.09, longitude: -95.71), latitudinalMeters: Measurement(value: 15, unit: UnitLength.miles).converted(to: .meters).value, longitudinalMeters: Measurement(value: 15, unit: UnitLength.miles).converted(to: .meters).value)
let annotations: [City] = [ ]

struct City: Identifiable {
    let id = UUID()
    let name: String
    let coordinate: CLLocationCoordinate2D
}

Originally posted by @kylepinionseb in #43

[stevengharris]

It turns out that a fix I made to allow the Split view to respond to changes in the split fraction caused this. I was a little worried at the time that there might be side-effects, but I could not find any. I believe you can fix the issue by removing or commenting out the following ~line 102 in Split.swift:

.onChange(of: fraction.value) { new in constrainedFraction = new }

I will have to follow-up with a fix that works in that case without screwing up yours. Unless you're also trying to set the fraction as discussed in #29, it should not impact you to remove this. Thanks.

[kylepinionseb]

Yes, disabling that line for me works. Thanks for the quick tip! I was experimenting with fraction, and it doesn't seem to cause a problem using that for an initial setting, and then the User can adjust and all seems well.