Block Scroll Down in Scrollview - Swiftui

How to only disable scroll in ScrollView but not content view?

Only pass .horizontal as the scroll axis if you want the view to scroll. Otherwise, pass the empty set.

struct TestView: View {
    @Binding var shouldScroll: Bool

    var body: some View {
        ScrollView(axes, showsIndicators: false) {
            Text("Your content here")
        }
    }

    private var axes: Axis.Set {
        return shouldScroll ? .horizontal : []
    }
}

Disable scrolling from bottom to top in swiftUI scroll view

Use LazyVGrid
and DragGesture
when changed, you only allow scroll to bottom.

struct ContentView: View {
    @State private var offset: CGFloat = .zero
    
    var columns: [GridItem] = Array(repeating: .init(.flexible()), count: 2)
    var body: some View {
        LazyVGrid(columns: columns) {
            ForEach((0...79), id: \.self) {
                let codepoint = $0 + 0x1f600
                let codepointString = String(format: "%02X", codepoint)
                Text("\(codepointString)")
                let emoji = String(Character(UnicodeScalar(codepoint)!))
                Text("\(emoji)")
            }
        }
        .font(.largeTitle)
        .offset(y: offset)
        .gesture(DragGesture().onChanged {value in
            let translation = value.translation.height
            if translation < 1 {
                offset = translation
            }
        })
    }
}

Update

You need to track the last offset when scrolling and reset it to zero each time you stop scrolling. This fixes the issue you have addressed in your comment.

struct ContentView: View {
    @State private var offset: CGFloat = .zero
    @State private var lastOffset: CGFloat = .zero
    
    var columns: [GridItem] = Array(repeating: .init(.flexible()), count: 2)
    var body: some View {
        LazyVGrid(columns: columns) {
            ForEach((0...79), id: \.self) {
                let codepoint = $0 + 0x1f600
                let codepointString = String(format: "%02X", codepoint)
                Text("\(codepointString)")
                let emoji = String(Character(UnicodeScalar(codepoint)!))
                Text("\(emoji)")
            }
        }
        .font(.largeTitle)
        .offset(y: offset)
        .gesture(DragGesture().onChanged {value in
            let translation = value.translation.height
            if  translation <= lastOffset {
                offset = translation
                lastOffset = translation
            }
        }.onEnded { value in
            lastOffset = .zero
        })
    }
}

You do not need to use LazyVGrid if you your Views are not too many.

SwiftUI: Disable ScrollView scrolling to top if top of screen is touched

This is not a SwiftUI or Xcode or ScrollView problem.

This is a built-in feature of iPhone.

When you tap the top-center edge of the screen, displayed contents will be scrolled up.

Try opening apps like Facebook, WhatsApp, then scroll and tap at the same position, you will see the displayed contents scroll up.

Stop vertical scroll in SwiftUI ScrollView

If ScrollView's height is less than the content's height it will scroll vertically too.

Just make it higher or the content narrower.

Prevent padding above Image at top of ScrollView when scrolling beyond limit in Sheet

Ok, here is possible solution for your case. Tested with Xcode 12b5 / iOS 14.

The idea is to have internal container, that scrolls inside, but reading its coordinate in scroll view coordinate space, compensate image position offsetting it relative to container, which continue scrolling, such giving effect that everything else, ie below image, still has bouncing.

demo

struct DemoView: View {
    var image: UIImage?

    @State private var offset = CGFloat.zero

    var body: some View {
        ScrollView {
            VStack { // internal container
                Image(uiImage: image ?? UIImage())
                    .resizable()
                    .aspectRatio((image?.size.width ?? 1) / (image?.size.height ?? 1), contentMode: .fill)
                    .background(Color(.secondarySystemFill))
                    .offset(y: offset < 0 ? offset : 0)      // compansate offset

                ForEach(0..<50) { index in
                    Text("\(index)")
                }
            }
            .background(GeometryReader {
                // read current position of container inside scroll view
                Color.clear.preference(key: ViewOffsetKey.self,
                    value: -$0.frame(in: .named("scroll")).origin.y)
            })
            .onPreferenceChange(ViewOffsetKey.self) {
                self.offset = $0   // needed offset to shift back image
            }
        }
        .coordinateSpace(name: "scroll")
    }
}

struct ViewOffsetKey: PreferenceKey {
    typealias Value = CGFloat
    static var defaultValue = CGFloat.zero
    static func reduce(value: inout Value, nextValue: () -> Value) {
        value += nextValue()
    }
}