SwiftUI - 如何在编辑模式下避免列表中的行缩进,但不使用 onDelete? (附code/video)

SwiftUI - how to avoid row indenting in List when in Edit Mode, but not using onDelete? (code/video attached)

在 SwiftUI 中,当我进入编辑模式但不使用 onDelete 时,如何避免行内容在我的列表中缩进?这是当前我的行内容在发生这种情况时缩进,就好像 "delete" 按钮将显示在左侧,但我没有使用 onDelete,所以那里没有按钮。

GIF 动画

代码摘录在这里:

var body: some View {
    VStack{
        List() {
            ForEach(gcTasks) { gcTask in
                HStack {
                    GCTaskRow(withGcTask: gcTask, haha: "")
                }
            }
            // .onDelete(perform: self.deleteTask)   // NOTE: HAVE REMOVED
            .onMove(perform: self.move)
        }
    }
    .environment(\.editMode, listInEditMode ? .constant(.active) : .constant(.inactive))
}

背景 - 实际上想要一直处于编辑模式,即总是可以选择拖动行 up/down,但是永远不会使用删除因此想要查看 onDelete 的所有痕迹,在这种情况下作为自动缩进..

更新:关于如何发生不需要的缩进的另一个例子(游乐场):

import SwiftUI
import PlaygroundSupport

let modelData: [String] = ["Eggs", "Milk", "Bread"]

struct ListTestNoDelete: View {
    private func move(from uiStartIndexSet: IndexSet, to uiDestIndex: Int) {
        print("On Move")
    }
    var body: some View {
        NavigationView {
            VStack {
                List {
                    ForEach(modelData, id: \.self) { str in
                        Text(str)
                    }
                    .onMove(perform: self.move)
                }
                .environment(\.editMode, .constant(.active))
                .navigationBarTitle( Text("Test") )
            }
        }
    }
}


let listTest = ListTestNoDelete()
PlaygroundPage.current.liveView = UIHostingController(rootView: listTest)

也许值得向 Apple 提交请求,但这是默认行为。目前可以使用以下解决方法。使用 Xcode 11.4 / iOS 13.4.

测试

struct DemoListEditMode: View {

    @State var items = ["a","b","c","d","e"]

    var body: some View {
        List {
            ForEach(items, id: \.self) { z in
                HStack {
                    Image(systemName: "checkmark.square") // just for demo
                    Text("\(z)")
                }
            }.onMove(perform: self.move)
            .listRowInsets(EdgeInsets(top: 0, leading: -24, // workaround !!
                bottom: 0, trailing: 0))                    
        }
        .environment(\.editMode, .constant(.active)) // persistent edit mode
    }

    func move(source: IndexSet, destination: Int) {
        self.items.move(fromOffsets: source, toOffset: destination)
    }
}

也许不是一个非常优雅的修复,但您可以将列表扩展到左侧。

List {
    // ...
}
// .padding(.leading, self.isEditing == .inactive ? 0 : -39)
.padding(.leading, self.isEditing ? -45 : 0)

更新:

我创建了一个 ListSelectionBoxWidthReader 来查找确切的选择框宽度,因为它似乎因设备和 iOS 版本而异。你可以在这个要点中找到它:https://gist.github.com/Amzd/2e1c56675109a005f11c77a7f2dbe224

struct ContentView: View  {
    
    /// this is the padding that the list adds in left for delete button when in the edit mode.
    /// I calculated the constant and works fine on iPhone11 but you will need to check for each device separately for accurate offset for every device.
    let listEditModeOffsetX = -UIScreen.main.bounds.width * 0.10647343
    
    @State var modelData: [String] = ["Eggs", "Milk", "Bread","Cake"]
    @State var editingList = false
    
    private func move(from source: IndexSet, to destination: Int) {
        modelData.move(fromOffsets: source, toOffset: destination)
        editingList = false
        print("On Move")
    }
    
    var body: some View {
        NavigationView {
            VStack {
                List {
                    ForEach(modelData, id: \.self) { str in
                        Text(str)
                            .offset(x: self.editingList ? listEditModeOffsetX : 0)
                    }
                    .onMove(perform: self.move)
                    .onLongPressGesture{
                        self.editingList = true
                    }
                    
                }
                .environment(\.editMode, editingList ? .constant(.active):.constant(.inactive))
                .navigationBarTitle( Text("Test") )
            }
        }
    }
}