我创建了一个符合 UIViewControllerRepresentable 的包装器。我创建了一个 UIViewController，其中包含一个启用了分页的 UIScrollView。自定义包装器可以正常工作。
SwiftyUIScrollView(.horizontal, pagingEnabled: true) {
NavigationLink(destination: Text("This is a test")) {
Text("Navigation Link Test")
}
}
此按钮显示为禁用并显示为灰色。点击它什么都不做。但是，如果将相同的按钮放在 ScrollView {} 包装器中，它就可以工作。
我在这里想念什么。这是自定义滚动视图类代码：
enum DirectionX {
case horizontal
case vertical
}
struct SwiftyUIScrollView<Content: View>: UIViewControllerRepresentable {
var content: () -> Content
var axis: DirectionX
var numberOfPages = 0
var pagingEnabled: Bool = false
var pageControlEnabled: Bool = false
var hideScrollIndicators: Bool = false
init(axis: DirectionX, numberOfPages: Int, pagingEnabled: Bool,
pageControlEnabled: Bool, hideScrollIndicators: Bool, @ViewBuilder content:
@escaping () -> Content) {
self.content = content
self.numberOfPages = numberOfPages
self.pagingEnabled = pagingEnabled
self.pageControlEnabled = pageControlEnabled
self.hideScrollIndicators = hideScrollIndicators
self.axis = axis
}
func makeUIViewController(context: Context) -> UIScrollViewController {
let vc = UIScrollViewController()
vc.axis = axis
vc.numberOfPages = numberOfPages
vc.pagingEnabled = pagingEnabled
vc.pageControlEnabled = pageControlEnabled
vc.hideScrollIndicators = hideScrollIndicators
vc.hostingController.rootView = AnyView(self.content())
return vc
}
func updateUIViewController(_ viewController: UIScrollViewController, context: Context) {
viewController.hostingController.rootView = AnyView(self.content())
}
}
class UIScrollViewController: UIViewController, UIScrollViewDelegate {
var axis: DirectionX = .horizontal
var numberOfPages: Int = 0
var pagingEnabled: Bool = false
var pageControlEnabled: Bool = false
var hideScrollIndicators: Bool = false
lazy var scrollView: UIScrollView = {
let view = UIScrollView()
view.delegate = self
view.isPagingEnabled = pagingEnabled
view.showsVerticalScrollIndicator = !hideScrollIndicators
view.showsHorizontalScrollIndicator = !hideScrollIndicators
return view
}()
lazy var pageControl : UIPageControl = {
let pageControl = UIPageControl()
pageControl.numberOfPages = numberOfPages
pageControl.currentPage = 0
pageControl.tintColor = UIColor.white
pageControl.pageIndicatorTintColor = UIColor.gray
pageControl.currentPageIndicatorTintColor = UIColor.white
pageControl.translatesAutoresizingMaskIntoConstraints = false
pageControl.isHidden = !pageControlEnabled
return pageControl
}()
var hostingController: UIHostingController<AnyView> = UIHostingController(rootView: AnyView(EmptyView()))
override func viewDidLoad() {
super.viewDidLoad()
view.addSubview(scrollView)
self.makefullScreen(of: self.scrollView, to: self.view)
self.hostingController.willMove(toParent: self)
self.scrollView.addSubview(self.hostingController.view)
self.makefullScreen(of: self.hostingController.view, to: self.scrollView)
self.hostingController.didMove(toParent: self)
view.addSubview(pageControl)
pageControl.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -50).isActive = true
pageControl.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
pageControl.heightAnchor.constraint(equalToConstant: 60).isActive = true
pageControl.widthAnchor.constraint(equalToConstant: 200).isActive = true
}
func makefullScreen(of viewA: UIView, to viewB: UIView) {
viewA.translatesAutoresizingMaskIntoConstraints = false
viewB.addConstraints([
viewA.leadingAnchor.constraint(equalTo: viewB.leadingAnchor),
viewA.trailingAnchor.constraint(equalTo: viewB.trailingAnchor),
viewA.topAnchor.constraint(equalTo: viewB.topAnchor),
viewA.bottomAnchor.constraint(equalTo: viewB.bottomAnchor),
])
}
func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
let currentIndexHorizontal = round(scrollView.contentOffset.x / self.view.frame.size.width)
let currentIndexVertical = round(scrollView.contentOffset.y / self.view.frame.size.height)
switch axis {
case .horizontal:
self.pageControl.currentPage = Int(currentIndexHorizontal)
break
case .vertical:
self.pageControl.currentPage = Int(currentIndexVertical)
break
default:
break
}
}
}
更新
这就是我使用包装器的方式：
struct TestData {
var id : Int
var text: String
}
struct ContentView: View {
var contentArray: [TestData] = [TestData(id: 0, text: "Test 1"), TestData(id: 1, text: "Test 2"), TestData(id: 2, text: "TEst 3"), TestData(id: 4, text: "Test 4")]
var body: some View {
NavigationView {
GeometryReader { g in
ZStack{
SwiftyUIScrollView(axis: .horizontal, numberOfPages: self.contentArray.count, pagingEnabled: true, pageControlEnabled: true, hideScrollIndicators: true) {
HStack(spacing: 0) {
ForEach(self.contentArray, id: \.id) { item in
TestView(data: item)
.frame(width: g.size.width, height: g.size.height)
}
}
}.frame(width: g.size.width)
}.frame(width: g.size.width, height: g.size.height)
.navigationBarTitle("Test")
}
}
}
}
struct TestView: View {
var data: TestData
var body: some View {
GeometryReader { g in
VStack {
HStack {
Spacer()
}
Text(self.data.text)
Text(self.data.text)
VStack {
NavigationLink(destination: Text("This is a test")) {
Text("Navigation Link Test")
}
}
Button(action: {
print("Do something")
}) {
Text("Button")
}
}.frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity)
.background(Color.yellow)
}
}
}
“导航链接测试”按钮显示为灰色。
