SwiftUI_CustomTabBar

gistfile1.txt

import SwiftUI

class ViewRouter: ObservableObject { @Published var iconName = "arrow.up.right.video.fill" }

struct ContentView: View {

    @ObservedObject var viewRouter = ViewRouter()
    @State private var selection: Int = 1

    var body: some View {
        GeometryReader { geometry in
            VStack {
                Spacer()
                Text(self.viewRouter.iconName)
                Spacer()
                HStack {
                    self.modifier(TabModifier(text: "arrow.up.right.video.fill", selection:  self.$selection, viewRouter: self.viewRouter, tag: 1))
                    self.modifier(TabModifier(text: "icloud.and.arrow.up.fill", selection:  self.$selection,viewRouter: self.viewRouter, tag: 2))
                    self.modifier(TabModifier(text: "lock.icloud.fill", selection:  self.$selection, viewRouter: self.viewRouter, tag: 3))
                    self.modifier(TabModifier(text: "message.fill", selection:  self.$selection,viewRouter: self.viewRouter, tag: 4))
                }
                .frame(width: geometry.size.width, height: geometry.size.height/10)
                .background(Color.white.shadow(radius: 2)).offset(x: 0, y: -10)
            }.edgesIgnoringSafeArea(.bottom).offset(x: 0, y: 10)
        }
    }
}

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

struct TabModifier: ViewModifier {

    var text: String?  = ""
    let selection: Binding<Int>
    var viewRouter: ViewRouter?
    var tag: Int
    var width = UIScreen.main.bounds.width

    func body(content: Content) -> some View {

        return GeometryReader { geometry in
            HStack {
                Image(systemName: self.text ?? "")
                    .resizable()
                    .aspectRatio(contentMode: .fit)
                    .padding(20)
                    .frame(width: geometry.size.width, height: self.width/4 - 20)
                    .foregroundColor(self.fgColor())
                    .onTapGesture {
                        self.selection.wrappedValue = self.tag
                        self.viewRouter?.iconName = self.text ?? ""
                }
            }
        }
    }

    private func fgColor() -> Color {
        return selection.wrappedValue == self.tag ? Color(UIColor.systemBlue) : Color(UIColor.systemGray)
    }
}