我有一个LazyVStack我只想更新一个视图而不是重新加载屏幕上的所有其他视图的视图。对于更复杂的单元,这会导致性能大幅下降。我已经包含了示例代码
import SwiftUI
struct ContentView: View {
@State var items = [String]()
var body: some View {
ScrollView {
LazyVStack {
ForEach(self.items, id: \.self) { item in
Button {
if let index = self.items.firstIndex(where: {$0 == item}) {
self.items[index] = "changed \(index)"
}
} label: {
cell(text: item)
}
}
}
}
.onAppear {
for _ in 0...200 {
self.items.append(NSUUID().uuidString)
}
}
}
}
struct cell: View {
let text: String
init(text: String) {
self.text = text
print("init …Run Code Online (Sandbox Code Playgroud)