002-stockpricetext

002-stockpricetext.swift

struct StockPriceText: View {
    
    class Context: ObservableObject {
        var lastPrice: Double?
        @Published var color: Color = Color.black
    }
    
    var price: Double
    @StateObject var context = Context()
    
    var body: some View {
                
        if let lastPrice = context.lastPrice {
            if price > lastPrice {
                context.color = .green
            }
            else if price < lastPrice {
                context.color = .red
            }
        }
        context.lastPrice = price

        return Text(String(price))
            .foregroundColor(context.color)
    }

    
    init(price: Double) {
        self.price = price
    }
}