1

我正在尝试UIViewController在 SwiftUI 视图中使用自定义。我设置了一个在方法UIViewControllerRepresentable中创建的类。这将创建并显示按钮,但是不占用任何空间。UIViewControllermakeUIViewControllerUIViewControllerUIViewControllerRepresentable

我尝试使用 aUIImagePickerController而不是我的自定义控制器,并且大小正确。我让控制器占用空间的唯一方法是UIViewControllerRepresentable在我的 SwiftUI 视图中设置一个固定框架,我绝对不想这样做。

注意:我确实需要使用 a UIViewController,因为我正在尝试UIMenuController在 SwiftUI 中实现 a。除了我遇到的这个问题之外,我所有的一切都可以正常工作,因为它的尺寸不正确。

这是我的代码:

struct ViewControllerRepresentable: UIViewControllerRepresentable {
    func makeUIViewController(context: Context) -> MenuViewController {
        let controller = MenuViewController()
        return controller
    }
    
    func updateUIViewController(_ uiViewController: MenuViewController, context: Context) {
        
    }
}

class MenuViewController: UIViewController {
    override func viewDidLoad() {
        let button = UIButton()
        button.setTitle("Test button", for: .normal)
        button.setTitleColor(.red, for: .normal)
        
        self.view.addSubview(button)
        button.translatesAutoresizingMaskIntoConstraints = false
        button.leadingAnchor.constraint(equalTo: self.view.leadingAnchor).isActive = true
        button.trailingAnchor.constraint(equalTo: self.view.trailingAnchor).isActive = true
        button.topAnchor.constraint(equalTo: self.view.topAnchor).isActive = true
        button.bottomAnchor.constraint(equalTo: self.view.bottomAnchor).isActive = true
    }
}

我的 SwiftUI 视图:

struct ClientView: View {
    var body: some View {
        VStack(spacing: 0) {
            EntityViewItem(copyValue: "copy value", label: {
                Text("Name")
            }, content: {
                Text("Random name")
            })
            .border(Color.green)
            
            ViewControllerRepresentable()
                .border(Color.red)
            
            EntityViewItem(copyValue: "copy value", label: {
                Text("Route")
            }, content: {
                HStack(alignment: .center) {
                    Text("Random route name")
                }
            })
            .border(Color.blue)
        }
    }
}

截屏:

问题截图

我对 UIKit 没有太多经验——我唯一的经验是编写 UIKit 视图以在 SwiftUI 中使用。这个问题很可能与我缺乏 UIKit 知识有关。

提前致谢!

编辑:

这是EntityViewItem. 我还将提供ClientView位于 - 中的容器视图EntityView

我还清理了其余代码并Entity用硬编码值替换了对的引用。

struct EntityViewItem<Label: View, Content: View>: View {
    var copyValue: String
    var label: Label
    var content: Content
    var action: (() -> Void)?
    
    init(copyValue: String, @ViewBuilder label: () -> Label, @ViewBuilder content: () -> Content, action: (() -> Void)? = nil) {
        self.copyValue = copyValue
        self.label = label()
        self.content = content()
        self.action = action
    }
    
    var body: some View {
        VStack(alignment: .leading, spacing: 2) {
            label
                .opacity(0.6)
            content
                .onTapGesture {
                    guard let unwrappedAction = action else {
                        return
                    }
                    unwrappedAction()
                }
                .contextMenu {
                    Button(action: {
                        UIPasteboard.general.string = copyValue
                    }) {
                        Text("Copy to clipboard")
                        Image(systemName: "doc.on.doc")
                    }
                }
        }
        .padding([.top, .leading, .trailing])
        .frame(maxWidth: .infinity, alignment: .leading)
    }
}

的容器ClientView

struct EntityView: View {
    let headerHeight: CGFloat = 56
    
    var body: some View {
        ZStack {
            ScrollView(showsIndicators: false) {
                VStack(spacing: 0) {
                    Color.clear.frame(
                        height: headerHeight
                    )
                    ClientView()
                }
            }
            VStack(spacing: 0) {
                HStack {
                    Button(action: {
                    }, label: {
                        Text("Back")
                    })
                    Spacer()
                    Text("An entity name")
                        .lineLimit(1)
                        .minimumScaleFactor(0.5)
                    
                    Spacer()
                    Color.clear
                        .frame(width: 24, height: 0)
                }
                .frame(height: headerHeight)
                .padding(.leading)
                .padding(.trailing)
                .background(
                    Color.white
                        .ignoresSafeArea()
                        .opacity(0.95)
                )
                Spacer()
            }
        }
    }
}
4

4 回答 4

2

正如@jnpdx 所提到的,您需要通过框架提供显式大小,以便可表示对象可见,因为它与其他视图一起嵌套在 VStack 中。

如果您有特定原因使用 UIViewController,请务必提供显式框架或创建 SwiftUI 视图。

struct ClientView: View {
  var body: some View {
    VStack(spacing: 0) {
        EntityViewItem(copyValue: "copy value", label: {
            Text("Name")
        }, content: {
            Text("Random name")
        })
        .border(Color.green)
        
        ViewControllerRepresentable()
            .border(Color.red)
            .frame(height: 100.0)
        
        EntityViewItem(copyValue: "copy value", label: {
            Text("Route")
        }, content: {
            HStack(alignment: .center) {
                Text("Random route name")
            }
        })
        .border(Color.blue)
    }
  }
}
于 2021-04-24T07:52:24.757 回答
2

非常感谢@udbhateja 和@jnpdx 的帮助。这很有意义,为什么UIViewControllerRepresentable当在ScrollView. 我最终找到了解决我的问题的方法,其中包括在UIViewControllerRepresentable. 基本上,我使用 aPreferenceKey来查找 SwiftUI 视图的高度,并设置框架UIViewControllerRepresentable以匹配它。

如果有人遇到同样的问题,这是我的代码:

struct EntityViewItem<Label: View, Content: View>: View {
    var copyValue: String
    var label: Label
    var content: Content
    var action: (() -> Void)?
    
    @State var height: CGFloat = 0
    
    init(copyValue: String, @ViewBuilder label: () -> Label, @ViewBuilder content: () -> Content, action: (() -> Void)? = nil) {
        self.copyValue = copyValue
        self.label = label()
        self.content = content()
        self.action = action
    }
    
    var body: some View {
        ViewControllerRepresentable(copyValue: copyValue) {
            SizingView(height: $height) { // This calculates the height of the SwiftUI view and sets the binding
                VStack(alignment: .leading, spacing: 2) {
                    // Content
                }
                .padding([.leading, .trailing])
                .padding(.top, 10)
                .padding(.bottom, 10)
                .frame(maxWidth: .infinity, alignment: .leading)
            }
        }
        .frame(height: height) // Here I set the height to the value returned from the SizingView
    }
}

和代码SizingView

struct SizingView<T: View>: View {
    
    let view: T
    @Binding var height: CGFloat
    
    init(height: Binding<CGFloat>, @ViewBuilder view: () -> T) {
        self.view = view()
        self._height = height
    }
    var body: some View {
        view.background(
            GeometryReader { proxy in
                Color.clear
                    .preference(key: SizePreferenceKey.self, value: proxy.size)
            }
        )
        .onPreferenceChange(SizePreferenceKey.self) { preferences in
            height = preferences.height
        }

    }
    
    func size(with view: T, geometry: GeometryProxy) -> T {
        height = geometry.size.height
        return view
    }
}

struct SizePreferenceKey: PreferenceKey {
    static var defaultValue: CGSize = .zero

    static func reduce(value: inout CGSize, nextValue: () -> CGSize) {
        value = nextValue()
    }
}

完成此操作后,我UIMenuController的功能完全正常。它有很多代码(如果 SwiftUI 中存在这个功能,我可能不得不写 5 行代码),但效果很好。如果有人想要代码,请发表评论,我会分享。

这是最终产品的图像: 在此处输入图像描述

于 2021-04-24T17:46:16.617 回答
0

如果其他人试图找到一个更简单的解决方案,则需要任何视图控制器并调整大小以适应其内容:

struct ViewControllerContainer: UIViewControllerRepresentable {
    let content: UIViewController
    
    class Coordinator: NSObject {
        var parent: ViewControllerContainer
        
        init(_ pageViewController: ViewControllerContainer) {
            self.parent = pageViewController
        }
    }

    init(_ content: UIViewController) {
        self.content = content
    }
    
    func makeCoordinator() -> Coordinator {
        Coordinator(ViewControllerContainer(content))
    }
        
    func makeUIViewController(context: UIViewControllerRepresentableContext<ViewControllerContainer>) -> UIViewController {
        let size = content.view.systemLayoutSizeFitting(UIView.layoutFittingCompressedSize)
        content.preferredContentSize = size
        return content
    }
    
    func updateUIViewController(_ uiViewController: UIViewController,
                                context: UIViewControllerRepresentableContext<ViewControllerContainer>) {
        
    }
}

然后,当您在 SwiftUI 中使用它时,请确保调用.fixedSize()

struct MainView: View {
    var body: some View {
        VStack(spacing: 0) {
 
            ViewControllerContainer(MenuViewController())
                .fixedSize()
 
        }
    }
}
于 2022-02-05T02:00:09.667 回答
0

对于任何寻找最简单解决方案的人来说,@Edudjr 的回答中有几行:

let size = content.view.systemLayoutSizeFitting(UIView.layoutFittingCompressedSize)
content.preferredContentSize = size

只需将其添加到您的 makeUIViewController 中!

于 2022-02-09T17:44:43.813 回答