From f9aa409a9254591806ba050b9fd8c26b2c0c432a Mon Sep 17 00:00:00 2001
From: Nicholas Bellucci <nickdbellucci@gmail.com>
Date: Tue, 12 May 2020 12:29:00 -0400
Subject: [PATCH] Removed need to pass selected index when initializing, readme
 updates

---
 Example/Example/ContentView.swift             |  3 +-
 README.md                                     | 28 +++++++++++++++--
 Sources/StatefulTabView/StatefulTabView.swift | 30 ++++++++++++++-----
 3 files changed, 49 insertions(+), 12 deletions(-)

diff --git a/Example/Example/ContentView.swift b/Example/Example/ContentView.swift
index 8d4b9bb..52774c9 100644
--- a/Example/Example/ContentView.swift
+++ b/Example/Example/ContentView.swift
@@ -9,11 +9,10 @@
 import SwiftUI
 
 struct ContentView: View {
-    @State var selectedIndex: Int = 0
     @State var badgeValue1: String? = "1"
     
     var body: some View {
-        StatefulTabView(selectedIndex: $selectedIndex) {
+        StatefulTabView {
             Tab(title: "Tab 1", systemImageName: "circle.fill", badgeValue: $badgeValue1) {
                 NavigationView {
                     List {
diff --git a/README.md b/README.md
index 67e5b89..013c191 100644
--- a/README.md
+++ b/README.md
@@ -24,7 +24,7 @@ In Xcode 11 or greater, navigate to `File > Swift Packages > Add Package Depende
 - [x] TabBarItem custom title and image
 - [x] TabBarItem badge value
 - [x] State retention from tab to tab
-- [x] Pop to root functionality when clicking selected index
+- [x] Pop to root functionality when selecting the already selected tab
 
 ## Usage
 
@@ -32,7 +32,7 @@ Setting up StatefulTabView is relatively simple and works similar to the native
 
 ### Basic
 ```Swift
-StatefulTabView(selectedIndex: $selectedIndex) {
+StatefulTabView {
     Tab(title: "Tab 1", systemImageName: "circle.fill") {
         NavigationView {
             List {
@@ -55,7 +55,7 @@ StatefulTabView(selectedIndex: $selectedIndex) {
 All appearance modifications can be made by using extensions for the StatefulTabView.
 
 ```Swift
-StatefulTabView(selectedIndex: $selectedIndex) {
+StatefulTabView {
     ...
 }
 .barTintColor(.red)
@@ -63,6 +63,16 @@ StatefulTabView(selectedIndex: $selectedIndex) {
 .barAppearanceConfiguration(.transparent)
 ```
 
+### Selected Index
+
+The selected index of the StatefulTabView can be set within the initializer. The passed value is a binding.
+
+```Swift
+StatefulTabView(selectedIndex: $selectedIndex) {
+    ...
+}
+```
+
 ### BadgeValue
 
 The TabBarItem badge value can be set in the initializer of a Tab. The passed value is a binding.
@@ -73,6 +83,18 @@ Tab(title: "Tab 1", systemImageName: "circle.fill", badgeValue: $badgeValue) {
 }
 ```
 
+### Single Tab
+
+Due to the limitations of the current `@_functionBuilder` implementation in Swift, to build a StatefulTabView with one tab `BuilderType.individual` should be passed within the initializer.
+
+```Swift
+StatefulTabView(.individual) {
+    Tab(title: "Tab 1", systemImageName: "circle.fill") {
+        ...
+    }
+}
+```
+
 ## License
 
 StatefulTabView is, and always will be, MIT licensed. See [LICENSE](LICENSE) for details.
diff --git a/Sources/StatefulTabView/StatefulTabView.swift b/Sources/StatefulTabView/StatefulTabView.swift
index 42a7095..b093eb9 100644
--- a/Sources/StatefulTabView/StatefulTabView.swift
+++ b/Sources/StatefulTabView/StatefulTabView.swift
@@ -19,28 +19,44 @@ public struct StatefulTabView: View {
     internal var backgroundColor: UIColor? = nil
     internal var tabBarConfiguration: TabBarBackgroundConfiguration? = nil
     
-    @Binding internal var selectedIndex: Int
+    @State private var stateIndex: Int = 0
+    @Binding private var bindableIndex: Int
     
-    public init(selectedIndex: Binding<Int>, _ type: BuilderType, _ content: () -> Tab) {
-        _selectedIndex = selectedIndex
+    private var useBindableIndex: Bool = false
+    
+    public init(selectedIndex: Binding<Int>? = nil, _ type: BuilderType, _ content: () -> Tab) {
+        if let selectedIndex = selectedIndex {
+            _bindableIndex = selectedIndex
+            useBindableIndex = true
+        } else {
+            _bindableIndex = .constant(0)
+            useBindableIndex = false
+        }
         
         let tabController = UIHostingController(rootView: content().view)
         tabController.tabBarItem = content().barItem
         viewControllers.append(tabController)
     }
     
-    public init(selectedIndex: Binding<Int>, @TabBuilder _ content: () -> [Tab]) {
-        _selectedIndex = selectedIndex
+    public init(selectedIndex: Binding<Int>? = nil, @TabBuilder _ content: () -> [Tab]) {
+        if let selectedIndex = selectedIndex {
+            _bindableIndex = selectedIndex
+            useBindableIndex = true
+        } else {
+            _bindableIndex = .constant(0)
+            useBindableIndex = false
+        }
+        
         configureViewControllers(with: content())
     }
-    
+
     public var body: some View {
         TabBarController(controllers: viewControllers,
                          tabBarItems: tabBarItems,
                          barTintColor: barTintColor,
                          backgroundColor: backgroundColor,
                          tabBarConfiguration: tabBarConfiguration,
-                         selectedIndex: $selectedIndex)
+                         selectedIndex: useBindableIndex ? $bindableIndex : $stateIndex)
             .edgesIgnoringSafeArea(.all)
     }
 }