Swiftui Gestures

// Single, double, and triple tap
TapGesture()            .onEnded { tapped.toggle() }
TapGesture(count: 2)    .onEnded { handleDoubleTap() }
TapGesture(count: 3)    .onEnded { handleTripleTap() }

// Shorthand modifier
Text("Tap me").onTapGesture(count: 2) { handleDoubleTap() }

// Basic long press (0.5s default)
LongPressGesture()
    .onEnded { _ in showMenu = true }

// Custom duration and distance tolerance
LongPressGesture(minimumDuration: 1.0, maximumDistance: 10)
    .onEnded { _ in triggerHaptic() }

@GestureState private var isPressing = false

Circle()
    .fill(isPressing ? .red : .blue)
    .scaleEffect(isPressing ? 1.2 : 1.0)
    .gesture(
        LongPressGesture(minimumDuration: 0.8)
            .updating($isPressing) { current, state, _ in state = current }
            .onEnded { _ in completedLongPress = true }
    )

@State private var offset = CGSize.zero

RoundedRectangle(cornerRadius: 16)
    .fill(.blue)
    .frame(width: 100, height: 100)
    .offset(offset)
    .gesture(
        DragGesture()
            .onChanged { value in offset = value.translation }
            .onEnded { _ in withAnimation(.spring) { offset = .zero } }
    )

DragGesture(minimumDistance: 20, coordinateSpace: .global)

@GestureState private var magnifyBy = 1.0

Image("photo")
    .resizable().scaledToFit()
    .scaleEffect(magnifyBy)
    .gesture(
        MagnifyGesture()
            .updating($magnifyBy) { value, state, _ in
                state = value.magnification
            }
    )

@State private var angle = Angle.zero

Rectangle()
    .fill(.blue).frame(width: 200, height: 200)
    .rotationEffect(angle)
    .gesture(
        RotateGesture(minimumAngleDelta: .degrees(1))
            .onChanged { value in angle = value.rotation }
    )

let magnify = MagnifyGesture()
    .onChanged { value in scale = value.magnification }

let rotate = RotateGesture()
    .onChanged { value in angle = value.rotation }

Image("photo")
    .scaleEffect(scale)
    .rotationEffect(angle)
    .gesture(magnify.simultaneously(with: rotate))

let longPressBeforeDrag = LongPressGesture(minimumDuration: 0.5)
    .sequenced(before: DragGesture())
    .onEnded { value in
        guard case .second(true, let drag?) = value else { return }
        finalOffset.width += drag.translation.width
        finalOffset.height += drag.translation.height
    }

let doubleTapOrLongPress = TapGesture(count: 2)
    .exclusively(before:
        LongPressGesture()
    )
    .onEnded { result in
        switch result {
        case .first(_): handleDoubleTap()
        case .second(_): handleLongPress()
        }
    }

@GestureState private var dragOffset = CGSize.zero  // resets to .zero
@State private var position = CGSize.zero            // persists

Circle()
    .offset(
        x: position.width + dragOffset.width,
        y: position.height + dragOffset.height
    )
    .gesture(
        DragGesture()
            .updating($dragOffset) { value, state, _ in
                state = value.translation
            }
            .onEnded { value in
                position.width += value.translation.width
                position.height += value.translation.height
            }
    )

let parentTap = TapGesture().onEnded { handleParent() }

VStack {
    Image(systemName: "star.fill")
        .onTapGesture { handleChild() }
}
.simultaneousGesture(parentTap) // Both handlers run on child content.

.gesture(drag, including: .gesture)   // added gesture; disables subview gestures
.gesture(drag, including: .subviews)  // subview gestures; disables added gesture
.gesture(drag, including: .all)       // default: added + subview gestures
.gesture(drag, including: .none)      // disables added + subview gestures

struct SwipeGesture: Gesture {
    enum Direction { case left, right, up, down }
    typealias Value = Direction

    let minimumDistance: CGFloat

    init(minimumDistance: CGFloat = 50) {
        self.minimumDistance = minimumDistance
    }

    var body: AnyGesture<Direction> {
        AnyGesture(
            DragGesture(minimumDistance: minimumDistance)
                .map { value in
                    let h = value.translation.width, v = value.translation.height
                    if abs(h) > abs(v) {
                        return h > 0 ? .right : .left
                    } else {
                        return v > 0 ? .down : .up
                    }
                }
        )
    }
}

// Usage
Rectangle().gesture(SwipeGesture().onEnded { print("Swiped \($0)") })

extension View {
    func onSwipe(perform action: @escaping (SwipeGesture.Direction) -> Void) -> some View {
        gesture(SwipeGesture().onEnded(action))
    }
}

// DON'T: No visual feedback during long press
LongPressGesture(minimumDuration: 2.0)
    .onEnded { _ in showResult = true }

// DO: Provide feedback while pressing
@GestureState private var isPressing = false

LongPressGesture(minimumDuration: 2.0)
    .updating($isPressing) { current, state, _ in
        state = current
    }
    .onEnded { _ in showResult = true }

// DON'T: Deprecated since iOS 17
MagnificationGesture()   // deprecated — use MagnifyGesture()

// DO: Use newer gesture types
MagnifyGesture()         // iOS 17+
RotateGesture()          // iOS 17+ (newer alternative to RotationGesture)

// DON'T: Expensive work called every frame (~60-120 Hz)
DragGesture()
    .onChanged { value in
        let result = performExpensiveHitTest(at: value.location)
        let filtered = applyComplexFilter(result)
        updateModel(filtered)
    }

// DO: Throttle or defer expensive work
DragGesture()
    .onChanged { value in
        dragPosition = value.location  // lightweight state update only
    }
    .onEnded { value in
        performExpensiveHitTest(at: value.location)  // once at end
    }

// DON'T: onTapGesture has no accessibility traits, VoiceOver role,
// Voice Control targeting, Switch Control scanning, or keyboard activation
Text("Delete")
    .onTapGesture { deleteItem() }

// DO: Button provides all of these automatically
Button("Delete", role: .destructive) { deleteItem() }

// DO: For custom visuals, use ButtonStyle instead of onTapGesture
Button { toggleExpanded() } label: {
    CardView()
}
.buttonStyle(.plain)