navigation+modal.swift

//
//  ContentView.swift
//  navigation
//
//  Created by Thomas Ricouard on 13/10/2019.
//  Copyright © 2019 Thomas Ricouard. All rights reserved.
//

import SwiftUI

struct RootView: View {
    @State private var isHomeShown = true
    @State private var isSettingShown = false
    @State private var selectedContent = "content1"
    
    var body: some View {
        ZStack {
            ContentView(content: $selectedContent,
                        isHomeShown: $isHomeShown,
                        isSettingShown: $isSettingShown)
                .blur(radius: isHomeShown ? 10 : 0)
                .scaleEffect(isHomeShown ? 0.8 : 1)
                .animation(.spring())
            if isHomeShown {
                HomeView(selectedContent: $selectedContent,
                         isHomeShown: $isHomeShown)
                    .transition(.scale)
                    .animation(.spring())
            }
            if isSettingShown {
                SettingsView(isShown: $isSettingShown)
                    .transition(.slide)
                    .animation(.spring())
            }
        }
    }
}

struct HomeView: View {
    let contents = ["content1", "content2", "content3", "content4"] 
    @Binding var selectedContent: String
    @Binding var isHomeShown: Bool
    
    var body: some View {
        ScrollView(.horizontal, showsIndicators: false) {
            HStack(spacing: 16) {
                ForEach(contents, id: \.self) { content in
                    Rectangle()
                        .foregroundColor(.blue)
                        .frame(width: 100, height: 150)
                        .onTapGesture {
                            self.selectedContent = content
                            self.isHomeShown = false
                    }
                }
            }.padding()
        }
    }
}

struct ContentView: View {
    @Binding var content: String
    @Binding var isHomeShown: Bool
    @Binding var isSettingShown: Bool
    
    var body: some View {
        GeometryReader { _ in
            VStack {
                Text(self.content)
                Button(action: {
                    self.isHomeShown = true
                }, label: {
                    Text("Back").foregroundColor(.blue)
                })
                Spacer()
                Button(action: {
                    self.isSettingShown = true
                }, label: {
                    Text("Settings").foregroundColor(.blue)
                })
                .padding()
            }
        }
        .background(Color.yellow)
        .frame(width: 300, height: 300)
    }
}

struct SettingsView: View {
    @Binding var isShown: Bool
    
    var body: some View {
        ZStack {
            RoundedRectangle(cornerRadius: 20)
                .fill(Color.white)
                .shadow(radius: 10)
            VStack {
                Text("Setting 1")
                Text("Setting 2")
                Button(action: {
                    self.isShown = false
                }, label: {
                    Text("Close").foregroundColor(.blue)
                })
            }
            .padding()
        }
        .frame(width: 250, height: 250)
    }
}

struct RootView_Previews: PreviewProvider {
    static var previews: some View {
        RootView()
    }
}