猜国旗应用的复习。

随机化数组顺序

shuffled()方法会自动为我们处理随机化数组顺序。

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var countries = ["Estonia", "France", "Germany", "Ireland", "Italy", "Nigeria", "Poland", "Russia", "Spain", "UK", "US"].shuffled()

胶囊形状裁剪

.clipShape(Capsule())

按钮中插入图片

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Image("Estonia")
    .renderingMode(.original)

生成随机数

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var correctAnswer = Int.random(in: 0...2)

该Int.random(in:)方法会自动选择一个随机数

代码

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//
//  ContentView.swift
//  Practise2-3
//
//  Created by 张洪Hoo on 2020/3/31.
//  Copyright © 2020 张洪Hoo. All rights reserved.
//

import SwiftUI

struct ContentView: View {
    @State private var counryList = ["Estonia", "France", "Germany", "Ireland", "Italy", "Nigeria", "Poland", "Russia", "Spain", "UK", "US"].shuffled()
    @State private var question = Int.random(in: 0...2)
    @State private var option = [String]()
    @State private var showAlert = false
    
    @State private var alertTitle = "猜对了！"
    @State private var alertDescription = "当前分数为 ？？？"
    
    
    var body: some View {
        ZStack {
            
            LinearGradient(gradient: Gradient(colors: [Color(#colorLiteral(red: 0.1017264351, green: 0.2405829132, blue: 0.8561289907, alpha: 1)), Color(#colorLiteral(red: 0, green: 0, blue: 0, alpha: 1))]), startPoint: .top, endPoint: .bottom)
            .edgesIgnoringSafeArea(.all)
                
            
            VStack {
                Text("Tap the flag of")
                .foregroundColor(Color.white)
                Text("\(self.counryList[self.question])")
                    .font(.largeTitle)
                .bold()
                    .foregroundColor(Color.white)
                ForEach(0 ..< 3, id: \.self) { item in
                    Button(action: {
                        if item == self.question {
                            self.alertTitle = "猜对了！"
                            self.alertDescription = "当前分数为 ？？？"
                            self.showAlert = true
                        }else {
                            self.alertTitle = "猜错了！"
                            self.alertDescription = "正确答案是\(self.counryList[self.question])，当前分数为 ？？？"
                            self.showAlert = true
                        }
                    }) {
                    Image(self.counryList[item])
                        .renderingMode(.original)
                        .clipShape(Capsule())
                        
                        }
                .padding()
                
                }
                
                
                Spacer()
            }
            
        }
    
        .alert(isPresented: $showAlert){
            Alert(---
title: Text(alertTitle), message: Text(alertDescription), dismissButton: .default(Text("继续")){
                self.askQuestion()
                })
            
        }
    }
    
    func askQuestion() {
        counryList.shuffle()
        question = Int.random(in: 0...2)
        
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

1792

SwiftPlayground 进度

1792