Update README.md

Author: swiftuiux

README.md

@@ -4,8 +4,80 @@
 ### Experimenting with navigation link. if you find this idea interesting you can expend it into more powerful solution.
 
 
+- The result navigaion definition
+```swift
+    var body: some View {
+        NavigationView{
+            VStack{
+                Button("go1") { route = .go1}
+                Button("go2") { route = .go2}
+                Button("go3") { route = .go3}
+            }.navigation(route: $route)
+        }.navigationViewStyle(.stack)
+    }
+```
+
 - Define sub view
+```swift
+struct SubView: View {
+
+    let text: String
+
+    var body: some View {
+        Text("\(text)")
+    }
+}
+```
+
 - Define routes
+```swift
+enum Router {
+    case go1
+    case go2
+    case go3
+    case empty
+
+    @ViewBuilder
+    var builder: some View {
+        switch(self) {
+        case .go1: SubView(text: "go1")
+        case .go2: SubView(text: "go2")
+        case .go3: SubView(text: "go3")
+        default: EmptyView()
+        }
+    }
+}
+```
 - Define view modifire
+```swift
+struct NavigationModifire : ViewModifier{
+    
+    @State var isActive :  Bool = true
+    
+    @Binding var route : Router
+    
+    func body(content: Content) -> some View {
+        content
+            .background{
+                NavigationLink(destination : route.builder, isActive: $isActive ){
+                    EmptyView()
+                }.hidden()
+            }
+            .onChange(of: isActive){
+                if $0 == false { route = .empty }
+            }
+    }
+    
+}
+
+extension View{
+    @ViewBuilder
+    func navigation(route : Binding<Router>) -> some View{
+        if route.wrappedValue != .empty{
+            modifier(NavigationModifire(route: route))
+        }else { self }
+    }
+}
+```
+
 
-- Apply modifire