ios - 带有 TextField 的 SwiftUI 列表在键盘出现/消失时进行调整

Question

我用 SwiftUI 编写了一个列表。我还有一个用作搜索栏的 TextField 对象。我的代码如下所示:

import SwiftUI

struct MyListView: View {
    @ObservedObject var viewModel: MyViewModel

    @State private var query = ""

    var body: some View {

        NavigationView {
            List {
                // how to listen for changes here?
                // if I add onEditingChange here, Get the value only after the user finish search (by pressing enter on the keyboard)
                TextField(String.localizedString(forKey: "search_bar_hint"), text: self.$query) {
                    self.fetchListing()
                } 

                ForEach(viewModel.myArray, id: \.id) { arrayObject in
                    NavigationLink(destination: MyDetailView(MyDetailViewModel(arrayObj: arrayObject))) {
                         MyRow(arrayObj: arrayObject)
                    }
                }
            }
            .navigationBarTitle(navigationBarTitle())
        }
        .onAppear(perform: fetchListing)
    }

    private func fetchListing() {
        query.isEmpty ? viewModel.fetchRequest(for: nil) : viewModel.fetchRequest(for: query)
    }

    private func navigationBarTitle() -> String {
        return query.isEmpty ? String.localizedString(forKey: "my_title") : query
    }
}

我现在遇到的问题是列表保留在键盘后面:(。我如何设置列表填充底部或边缘插入(或其他有效的，我完全打开)，以便列表的滚动在上面结束键盘？列表“大小”也应该根据键盘是否打开或关闭自动调整。

问题如下:

请帮我提供任何建议，我真的不知道该怎么做:(。我是一个 SwiftUI 初学者，正在尝试学习它:)。

Answer 1

您可以尝试以下方法并自行添加详细的动画。

@ObservedObject var keyboard = KeyboardResponder()
var body: some View {

    NavigationView {

        List {
            // how to listen for changes here?
            // if I add onEditingChange here, Get the value only after the user finish search (by pressing enter on the keyboard)
            TextField("search_bar_hint", text: self.$query) {
                self.fetchListing()
            }

            ForEach(self.viewModel, id: \.self) { arrayObject in
                Text(arrayObject)
            }

        }.padding(.bottom, self.keyboard.currentHeight).animation(.easeIn(duration: self.keyboard.keyboardDuration))
            .navigationBarTitle(self.navigationBarTitle())
    }
    .onAppear(perform: fetchListing)
}





class KeyboardResponder: ObservableObject {
@Published var currentHeight: CGFloat = 0
@Published var keyboardDuration: TimeInterval = 0
private var anyCancellable: Set<AnyCancellable> = Set<AnyCancellable>()

init() {
    let publisher1 = NotificationCenter.Publisher(center: .default, name: UIResponder.keyboardWillShowNotification).map{ notification -> Just<(CGFloat, TimeInterval)> in
    guard let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue else {return Just((CGFloat(0.0), 0.0)) }
    guard let duration:TimeInterval = notification.userInfo?[UIResponder.keyboardAnimationDurationUserInfoKey] as? Double else { return Just((CGFloat(0.0), 0.0)) }
    return Just((keyboardSize.height, duration))}

    let publisher2 = NotificationCenter.Publisher(center: .default, name: UIResponder.keyboardWillHideNotification) .map{ notification -> Just<(CGFloat, TimeInterval)> in
           guard let duration:TimeInterval = notification.userInfo?[UIResponder.keyboardAnimationDurationUserInfoKey] as? Double else { return Just((CGFloat(0.0), 0.0)) }
               return Just((0.0, duration))}

    Publishers.Merge(publisher1, publisher2).switchToLatest().subscribe(on: RunLoop.main).sink(receiveValue: {
            if $0.1 > 1e-6 { self.currentHeight = $0.0 }
            self.keyboardDuration = $0.1
        }).store(in: &anyCancellable)
}
}