Add presentation playgrounds (Navigation, TabView, Sheet, Alert)

Author: colemancda

Demo/App.swiftpm/Sources/PresentationPlaygrounds.swift

@@ -0,0 +1,108 @@
+#if canImport(AndroidSwiftUI)
+import AndroidSwiftUI
+#else
+import SwiftUI
+#endif
+
+struct NavigationPlayground: View {
+    var body: some View {
+        ScrollView {
+            VStack(alignment: .leading, spacing: 16) {
+                Text("Value-based navigation").padding()
+                NavigationLink("Push value 1", value: 1)
+                NavigationLink("Push value 2", value: 2)
+                Divider()
+                Text("Classic navigation").padding()
+                NavigationLink("Push a destination view", destination: NavDetail(label: "Pushed directly"))
+            }
+        }
+        .navigationDestination(for: Int.self) { value in
+            NavDetail(label: "Value \(value)", next: value + 1)
+        }
+    }
+}
+
+struct NavDetail: View {
+    let label: String
+    var next: Int? = nil
+    @Environment(\.dismiss) private var dismiss
+    var body: some View {
+        VStack(spacing: 16) {
+            Text(label)
+            if let next, next <= 4 {
+                NavigationLink("Push value \(next)", value: next)
+            }
+            Button("Pop with dismiss") { dismiss() }
+        }
+        .padding()
+        .navigationTitle(label)
+    }
+}
+
+struct TabViewPlayground: View {
+    @State private var selection = 0
+    var body: some View {
+        TabView(selection: $selection) {
+            VStack(spacing: 16) {
+                Text("First tab content")
+                Button("Jump to third tab") { selection = 2 }
+            }
+            .tabItem { Text("One") }.tag(0)
+            Text("Second tab content").tabItem { Text("Two") }.tag(1)
+            Text("Third tab content").tabItem { Text("Three") }.tag(2)
+        }
+    }
+}
+
+struct SheetPlayground: View {
+    @State private var full = false
+    @State private var medium = false
+    var body: some View {
+        ScrollView {
+            VStack(spacing: 16) {
+                Button("Present full-size sheet") { full = true }
+                Button("Present medium detent sheet") { medium = true }
+            }
+            .padding()
+        }
+        .sheet(isPresented: $full) {
+            SheetBody(title: "Full-size sheet")
+        }
+        .sheet(isPresented: $medium) {
+            SheetBody(title: "Medium sheet").presentationDetents([.medium])
+        }
+    }
+}
+
+struct SheetBody: View {
+    let title: String
+    @Environment(\.dismiss) private var dismiss
+    var body: some View {
+        VStack(spacing: 16) {
+            Text(title)
+            Button("Dismiss") { dismiss() }
+        }
+        .padding()
+    }
+}
+
+struct AlertPlayground: View {
+    @State private var simple = false
+    @State private var confirm = false
+    @State private var result = "No choice yet"
+    var body: some View {
+        ScrollView {
+            VStack(spacing: 16) {
+                Button("Show simple alert") { simple = true }
+                Button("Show confirmation") { confirm = true }
+                Text(result)
+            }
+            .padding()
+        }
+        .alert("A simple alert", isPresented: $simple, message: "This is the message body.")
+        .alert("Delete item?", isPresented: $confirm, message: "This cannot be undone.", buttons: [
+            AlertButton("Cancel", role: .cancel) { result = "Cancelled" },
+            AlertButton("Delete", role: .destructive) { result = "Deleted" },
+        ])
+    }
+}