如何解决自定义基于手势的滑动卡中的ScrollView导致SwiftUI中出现问题
我已经制作了一个最小的可复制示例,将在下面粘贴。只需将其插入Xcode,您就会明白这笔交易是什么。本质上,我有一个自定义的Slide-Up卡。当枚举位置为.top时,我在Xcode模拟器中滑动ScrollView时,它会导致卡的位置发生轻微偏移。有什么方法可以锁定卡的位置?还是至少可以做到这一点,以使滑动卡内的ScrollView不会因滑动手势而出现问题?
内容视图:
struct ContentView : View {
var body: some View {
ZStack(alignment: Alignment.top) {
Text("test")
.frame(width: UIScreen.main.bounds.width,height: UIScreen.main.bounds.height)
.background(Color.red)
SlideOverCard {
VStack {
ScrollView {
VStack {
ForEach(1..<100) { _ in
Text("test")
}
}.frame(width: UIScreen.main.bounds.width)
}
Text("TESTER LINE OF TEXT")
Spacer()
}.frame(width: UIScreen.main.bounds.width)
}
}
.edgesIgnoringSafeArea(.vertical)
}
}
插卡:
struct SlideOverCard<Content: View> : View {
@GestureState private var dragState = DragState.inactive
@State var position = CardPosition.top
var content: () -> Content
var body: some View {
let drag = DragGesture()
.updating($dragState) { drag,state,transaction in
state = .dragging(translation: drag.translation)
}
.onEnded(onDragEnded)
return Group {
Handle()
self.content()
}
.frame(width: UIScreen.main.bounds.width,height: UIScreen.main.bounds.height)
.background(Color.white)
.cornerRadius(10.0)
.shadow(color: Color(.sRGBLinear,white: 0,opacity: 0.13),radius: 10.0)
.offset(y: self.position.rawValue + self.dragState.translation.height)
.animation(self.dragState.isDragging ? nil : .interpolatingSpring(stiffness: 300.0,damping: 30.0,initialVelocity: 10.0))
.gesture(drag)
}
private func onDragEnded(drag: DragGesture.Value) {
let verticalDirection = drag.predictedEndLocation.y - drag.location.y
let cardTopEdgeLocation = self.position.rawValue + drag.translation.height
let positionAbove: CardPosition
let positionBelow: CardPosition
let closestPosition: CardPosition
if cardTopEdgeLocation <= CardPosition.middle.rawValue {
positionAbove = .top
positionBelow = .middle
} else {
positionAbove = .middle
positionBelow = .bottom
}
if (cardTopEdgeLocation - positionAbove.rawValue) < (positionBelow.rawValue - cardTopEdgeLocation) {
closestPosition = positionAbove
} else {
closestPosition = positionBelow
}
if verticalDirection > 0 {
self.position = positionBelow
} else if verticalDirection < 0 {
self.position = positionAbove
} else {
self.position = closestPosition
}
}
}
enum CardPosition: CGFloat {
case top = 100
case middle = 500
case bottom = 850
}
enum DragState {
case inactive
case dragging(translation: CGSize)
var translation: CGSize {
switch self {
case .inactive:
return .zero
case .dragging(let translation):
return translation
}
}
var isDragging: Bool {
switch self {
case .inactive:
return false
case .dragging:
return true
}
}
}
句柄:
struct Handle : View {
private let handleThickness = CGFloat(5.0)
var body: some View {
RoundedRectangle(cornerRadius: handleThickness / 2.0)
.frame(width: 40,height: handleThickness)
.foregroundColor(Color.secondary)
.padding(5)
}
}
解决方法
好吧,我设法重现了你的意思...
通过Xcode 12 / iOS 14测试
更新:在此处找到了解决方法
ScrollView {
VStack {
ForEach(1..<100) { _ in
Text("test")
}
}.frame(width: UIScreen.main.bounds.width)
}
.background(Color.white) // << make opaque background
.highPriorityGesture(DragGesture()) // << block below DragGesture
我也考虑将变体移动到“手柄”上(如您所愿)
return VStack { // << make it instead of Group
Handle()
.gesture(drag) // << here !!
self.content()
}
.frame(width: UIScreen.main.bounds.width,height: UIScreen.main.bounds.height)
.background(Color.white)
.cornerRadius(10.0)
.shadow(color: Color(.sRGBLinear,white: 0,opacity: 0.13),radius: 10.0)
.offset(y: self.position.rawValue + self.dragState.translation.height)
.animation(self.dragState.isDragging ? nil : .interpolatingSpring(stiffness: 300.0,damping: 30.0,initialVelocity: 10.0))
版权声明:本文内容由互联网用户自发贡献,该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 dio@foxmail.com 举报,一经查实,本站将立刻删除。