How to display the value of a chart item when it is pressed

[acumen1005]

i want to display the value of yellow item on the chart the it is pressed。

[MrKrasnov]

Example:

import SwiftUI
import Charts

struct ContentView: View {
    let data: [Double] = [0.1, 0.3, 0.2, 0.5, 0.4, 0.9, 0.1]
    @State private var hintPosition: CGPoint? = nil
    @State private var hintValue: String? = nil

    var body: some View {
        GeometryReader { geometry in
            ZStack {
                Chart(data: data)
                    .chartStyle(
                        LineChartStyle(.quadCurve, lineColor: .blue, lineWidth: 5)
                    )
                    .frame(height: 300)
                    .gesture(
                        DragGesture(minimumDistance: 0)
                            .onChanged { value in

                                hintPosition = value.location
                                let index = Int((value.location.x / geometry.size.width) * CGFloat(data.count))
                                if index >= 0 && index < data.count {
                                    hintValue = String(format: "Value: %.2f", data[index])
                                } else {
                                    hintValue = nil
                                }
                            }
                            .onEnded { _ in
                                hintPosition = nil
                                hintValue = nil
                            }
                    )

                // Hint
                if let hintPosition = hintPosition, let hintValue = hintValue {
                    VStack {
                        Text(hintValue)
                            .padding(5)
                            .background(Color.white.opacity(0.8))
                            .cornerRadius(8)
                            .shadow(radius: 3)
                            .position(x: hintPosition.x, y: hintPosition.y - 20)
                    }
                }
            }
            .frame(height: 300)
            .padding()
        }
    }
}

I added properties:
@State private var hintPosition: CGPoint? = nil
@State private var hintValue: String? = nil

Used the functionality of GeometryReader and ZStack. Inner Chart i set .gesture

.gesture(
    DragGesture(minimumDistance: 0)
        .onChanged { value in

            hintPosition = value.location
            let index = Int((value.location.x / geometry.size.width) * CGFloat(data.count))
            if index >= 0 && index < data.count {
                hintValue = String(format: "Value: %.2f", data[index])
            } else {
                hintValue = nil
            }
        }
        .onEnded { _ in
            hintPosition = nil
            hintValue = nil
        }
)

To display Hint I used the following

if let hintPosition = hintPosition, let hintValue = hintValue {
    VStack {
        Text(hintValue)
            .padding(5)
            .background(Color.white.opacity(0.8))
            .cornerRadius(8)
            .shadow(radius: 3)
            .position(x: hintPosition.x, y: hintPosition.y - 20)
    }
}