在SwiftUI 2.0中,你可以使用ScrollViewReader实现以下功能。
首先,在你的列表中,每个元素都必须有一个唯一的ID,这个ID可以是任何可哈希对象。只需使用.id修饰符即可。例如:
List(0..<10) { i in
Text("Row \(i)")
.id(i)
}
之后,您可以按照以下方式使用ScrollViewReader:
ScrollViewReader { scroll in
VStack {
Button("Jump to row #10") {
scroll.scrollTo(10)
}
List(0..<10) { i in
Text("Row \(i)")
.id(i)
}
}
}
struct AlphaScroller: View {
let alphabet = ["a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"]
let sampleItems = ["Apple", "Banana", "Orange"]
var body: some View {
ScrollView {
ScrollViewReader{ scroll in
VStack {
//top character picker with horizontal Scrolling
ScrollView(.horizontal) {
HStack(spacing: 20) {
ForEach(alphabet, id: \.self) { char in
Button(char){
withAnimation {
scroll.scrollTo(char, anchor: .top)
}
}
}
}
}.frame(width: UIScreen.main.bounds.width * 0.8, height: 20)
//list of sections
ForEach(alphabet, id: \.self){ char in
HStack {
VStack {
Text(char).id(char)
.font(.system(size: 30))
.padding()
ForEach(sampleItems, id: \.self){ item in
Text(item)
.padding()
}
Rectangle()
.foregroundColor(.gray)
.frame(width: UIScreen.main.bounds.width, height: 1)
}
Spacer()
}
}
}
}
}
}
}