How to Get Row Index in Swiftui List

How to get row index in SwiftUI List?

Using .indices() is not a workaround, it is a proper way of doing it.

Alternatively, you can also use the code in the release notes for an indexed() array:

struct ContentView: View {
    var persons = ["Boris", "Anna", "Tom"]

    var body: some View {
        VStack {
            List(persons.indexed(), id: \.1.self) { idx, person in
                Text("\(idx) - \(person)")
            }
        }
    }
}


// This is taken from the Release Notes, with a typo correction, marked below
struct IndexedCollection<Base: RandomAccessCollection>: RandomAccessCollection {
    typealias Index = Base.Index
    typealias Element = (index: Index, element: Base.Element)

    let base: Base

    var startIndex: Index { base.startIndex }

   // corrected typo: base.endIndex, instead of base.startIndex
    var endIndex: Index { base.endIndex }

    func index(after i: Index) -> Index {
        base.index(after: i)
    }

    func index(before i: Index) -> Index {
        base.index(before: i)
    }

    func index(_ i: Index, offsetBy distance: Int) -> Index {
        base.index(i, offsetBy: distance)
    }

    subscript(position: Index) -> Element {
        (index: position, element: base[position])
    }
}

extension RandomAccessCollection {
    func indexed() -> IndexedCollection<Self> {
        IndexedCollection(base: self)
    }
}

How to get the index of the element in the List in SwiftUI when the List is populated with the array?

This can be done using using .enumerated. For your MenuItem values it will be as follows

List {
    ForEach(Array(menuItems.enumerated()), id: \.1.id) { (index, textItem) in
        // do with `index` anything needed here
        Text(textItem.text)
    }
}

How to get on screen rows from List in SwiftUI?

You can use onAppear and onDisappear functions to maintain a list of visible rows and then use these to find a visible index.

struct ContentView: View {
    let rows = (Unicode.Scalar("A").value...Unicode.Scalar("Z").value)
        .map { String(Unicode.Scalar($0)!) }

    @State var visibleRows: Set<String> = []

    var body: some View {
        List(rows, id: \.self) { row in
            HStack {
                Text(row)
                    .padding(40)
                    .onAppear { self.visibleRows.insert(row) }
                    .onDisappear { self.visibleRows.remove(row) }
            }
            Spacer()
            Text(self.getVisibleIndex(for: row)?.description ?? "")
        }
    }

    func getVisibleIndex(for row: String) -> Int? {
        visibleRows.sorted().firstIndex(of: row)
    }
}

How to get the index of a dynamic List / ForEach bindable element (new Xcode 13's syntax)?

You can build wrapper by yourself:

struct ListIndexed<Content: View>: View {
    let list: List<Never, Content>
    
    init<Data: MutableCollection&RandomAccessCollection, RowContent: View>(
        _ data: Binding<Data>,
        @ViewBuilder rowContent: @escaping (Data.Index, Binding<Data.Element>) -> RowContent
    ) where Content == ForEach<[(Data.Index, Data.Element)], Data.Element.ID, RowContent>,
    Data.Element : Identifiable,
    Data.Index : Hashable
    {
        list = List {
            ForEach(
                Array(zip(data.wrappedValue.indices, data.wrappedValue)),
                id: \.1.id
            ) { i, _ in
                rowContent(i, Binding(get: { data.wrappedValue[i] }, set: { data.wrappedValue[i] = $0 }))
            }
        }
    }
    
    var body: some View {
        list
    }
}

Usage:

ListIndexed($items) { i, $item in
    HStack {
        Text("Index \(i)")
        TextField("", text: $item.text)
    }
}

SwiftUI - How to get the selected index of a list when you have a search?

The solution by Aperi is not good, because the only elements tappable will be the texts, not the cells.

The correct answer is to wrap the Text element as a view of a Button, like shown on this video...

Button(action: {
  // do something()            
}) {
   Text(item.term!)
}

Get index number of CoreData at List in SwiftUI

Here is a possible approach

ForEach(self.toDoItems.indices, id: \.self) { index in
    HStack{
        Text("\(toDoItems[index].title!)")
        
    }.onTapGesture {
        
        print("Print current Index: \(index)")
    }
}

Get index in ForEach in SwiftUI

This works for me:

Using Range and Count

struct ContentView: View {
    @State private var array = [1, 1, 2]

    func doSomething(index: Int) {
        self.array = [1, 2, 3]
    }
    
    var body: some View {
        ForEach(0..<array.count) { i in
          Text("\(self.array[i])")
            .onTapGesture { self.doSomething(index: i) }
        }
    }
}

Using Array's Indices

The indices property is a range of numbers.

struct ContentView: View {
    @State private var array = [1, 1, 2]

    func doSomething(index: Int) {
        self.array = [1, 2, 3]
    }
    
    var body: some View {
        ForEach(array.indices) { i in
          Text("\(self.array[i])")
            .onTapGesture { self.doSomething(index: i) }
        }
    }
}

How to get the index of a deleted row from a list in SwiftUI?

If you remove by-one, then the following give you index of deleted row

func delete(at offsets: IndexSet) {     
      self.symptoms.remove(atOffsets: offsets)

      // here I want to make the HTTP request
      let index = offsets[offsets.startIndex]

      // ... use index in HTTP request
}

SwiftUI How do I record the index of the grid item that is currently being displayed on CollectionView?

Found a super easy solution to this problem. This does the snap to item and passes an index, just like an old collection view would.

I added an @State var selection: Int = 0 to the ContentView, and "selection" Bindings to the map and results view.

Then I replaced the Collection View Controller section with this:

TabView(selection: $selection)  {
  ForEach(Array(zip(results.indices, results)), id: \.0) { index, result in
    ResultCardView(place: result[0]).tag(index)
  }
}
.tabViewStyle(PageTabViewStyle(indexDisplayMode: .always))

It does exactly what I want, and took me five minutes to implement.
I found that solution here: https://swiftwithmajid.com/2020/09/16/tabs-and-pages-in-swiftui/

---

Related Topics