xmartlabs · aehlke · Feb 17, 2023 · Feb 17, 2023 · Apr 6, 2023 · Nov 2, 2023
diff --git a/Package.swift b/Package.swift
@@ -3,7 +3,7 @@ import PackageDescription
 
 let package = Package(
     name: "PagerTabStripView",
-    platforms: [.iOS(.v16), .macOS(.v13)],
+    platforms: [.iOS(.v15), .macOS(.v12)],
     products: [
         .library(name: "PagerTabStripView", targets: ["PagerTabStripView"])
     ],

diff --git a/Sources/NavBarItem.swift b/Sources/NavBarItem.swift
@@ -8,16 +8,16 @@
 import SwiftUI
 
 struct NavBarItem<SelectionType>: View, Identifiable where SelectionType: Hashable {
-
+    
     var id: SelectionType
     @Binding private var selection: SelectionType
     @EnvironmentObject private var pagerSettings: PagerSettings<SelectionType>
-
+    
     public init(id: SelectionType, selection: Binding<SelectionType>) {
         self.id = id
         self._selection = selection
     }
-
+    
     @MainActor var body: some View {
         if let dataItem = pagerSettings.items[id] {
             dataItem.view

diff --git a/Sources/NavBarModifier.swift b/Sources/NavBarModifier.swift
@@ -5,6 +5,7 @@
 //  Copyright © 2022 Xmartlabs SRL. All rights reserved.
 //
 
+#if os(iOS)
 import SwiftUI
 
 struct NavBarModifier<SelectionType>: ViewModifier where SelectionType: Hashable {
@@ -17,12 +18,12 @@ struct NavBarModifier<SelectionType>: ViewModifier where SelectionType: Hashable
     @MainActor func body(content: Content) -> some View {
         VStack(alignment: .leading, spacing: 0) {
             if !style.placedInToolbar {
-                NavBarWrapperView(selection: $selection)
+                NavBarWrapperView<SelectionType>(selection: $selection)
                 content
             } else {
                 content.toolbar(content: {
                     ToolbarItem(placement: .principal) {
-                        NavBarWrapperView(selection: $selection)
+                        NavBarWrapperView<SelectionType>(selection: $selection)
                     }
                 })
             }
@@ -40,17 +41,22 @@ private struct NavBarWrapperView<SelectionType>: View where SelectionType: Hasha
         case let barStyle as BarStyle:
             IndicatorBarView<SelectionType, AnyView>(selection: $selection, indicator: barStyle.indicatorView)
         case is SegmentedControlStyle:
-            SegmentedNavBarView(selection: $selection)
+            SegmentedNavBarView<SelectionType>(selection: $selection)
         case let indicatorStyle as BarButtonStyle:
-            if indicatorStyle.scrollable {
-                ScrollableNavBarView(selection: $selection)
+            if #available(iOS 16, *) {
+                if indicatorStyle.scrollable {
+                    ScrollableNavBarView<SelectionType>(selection: $selection)
+                } else {
+                    FixedSizeNavBarView<SelectionType>(selection: $selection)
+                }
             } else {
-                FixedSizeNavBarView(selection: $selection)
+                SegmentedNavBarView<SelectionType>(selection: $selection)
             }
         default:
-            SegmentedNavBarView(selection: $selection)
+            SegmentedNavBarView<SelectionType>(selection: $selection)
         }
     }
 
     @Environment(\.pagerStyle) var style: PagerStyle
 }
+#endif
diff --git a/Sources/NavigationBarStyles/FixedSizeNavBarView.swift b/Sources/NavigationBarStyles/FixedSizeNavBarView.swift
@@ -8,6 +8,7 @@
 import Foundation
 import SwiftUI
 
+@available(iOS 16.0, macOS 13.0, *)
 internal struct FixedSizeNavBarView<SelectionType>: View where SelectionType: Hashable {
 
     @Binding private var selection: SelectionType
@@ -24,8 +25,11 @@ internal struct FixedSizeNavBarView<SelectionType>: View where SelectionType: Ha
             Group {
                 FixedSizeNavBarViewLayout(spacing: internalStyle.tabItemSpacing) {
                     ForEach(pagerSettings.itemsOrderedByIndex, id: \.self) { tag in
-                        NavBarItem(id: tag, selection: $selection)
-                            .tag(tag)
+                        if let dataItem = pagerSettings.items[tag] {
+                            NavBarItem(id: tag, selection: $selection)
+                                .tag(tag)
+                                .id(dataItem.id)
+                        }
                     }
                     internalStyle.indicatorView()
                         .frame(height: internalStyle.indicatorViewHeight)
@@ -50,6 +54,7 @@ internal struct FixedSizeNavBarView<SelectionType>: View where SelectionType: Ha
 
 }
 
+@available(iOS 16.0, macOS 13.0, *)
 struct FixedSizeNavBarViewLayout: Layout {
 
     let spacing: CGFloat

diff --git a/Sources/NavigationBarStyles/ScrollableNavBarView.swift b/Sources/NavigationBarStyles/ScrollableNavBarView.swift
@@ -8,6 +8,7 @@
 import Foundation
 import SwiftUI
 
+@available(iOS 16.0, macOS 13.0, *)
 internal struct ScrollableNavBarView<SelectionType>: View where SelectionType: Hashable {
 
     @Binding var selection: SelectionType
@@ -25,8 +26,11 @@ internal struct ScrollableNavBarView<SelectionType>: View where SelectionType: H
                 ScrollView(.horizontal, showsIndicators: false) {
                     ScrollableNavBarViewLayout(spacing: internalStyle.tabItemSpacing) {
                         ForEach(pagerSettings.itemsOrderedByIndex, id: \.self) { tag in
-                            NavBarItem(id: tag, selection: $selection)
-                                .tag(tag)
+                            if let dataItem = pagerSettings.items[tag] {
+                                NavBarItem(id: tag, selection: $selection)
+                                   .tag(tag)
+                                   .id(dataItem.id)
+                            }
                         }
                         internalStyle.indicatorView()
                             .frame(height: internalStyle.indicatorViewHeight)
@@ -66,6 +70,7 @@ internal struct ScrollableNavBarView<SelectionType>: View where SelectionType: H
     }
 }
 
+@available(iOS 16.0, macOS 13.0, *)
 struct ScrollableNavBarViewLayout: Layout {
 
     private let spacing: CGFloat

diff --git a/Sources/NavigationBarStyles/SegmentedNavBarView.swift b/Sources/NavigationBarStyles/SegmentedNavBarView.swift
@@ -21,8 +21,14 @@ internal struct SegmentedNavBarView<SelectionType>: View where SelectionType: Ha
             Picker("SegmentedNavBarView", selection: $selection) {
                 if pagerSettings.items.count > 0 && pagerSettings.width > 0 {
                     ForEach(pagerSettings.itemsOrderedByIndex, id: \.self) { tag in
-                        NavBarItem(id: tag, selection: $selection)
-                            .tag(tag)
+                        if let dataItem = pagerSettings.items[tag] {
+                            NavBarItem(id: tag, selection: $selection)
+                                .tag(tag)
+                                .id(dataItem.id)
+                        } else {
+                            NavBarItem(id: tag, selection: $selection)
+                                .tag(tag)
+                        }
                     }
                 }
             }

diff --git a/Sources/PagerSettings.swift b/Sources/PagerSettings.swift
@@ -8,18 +8,20 @@
 import SwiftUI
 
 struct DataItem<SelectedType>: Identifiable, Equatable where SelectedType: Hashable {
-
     static func == (lhs: DataItem<SelectedType>, rhs: DataItem<SelectedType>) -> Bool {
-        return lhs.tag == rhs.tag
+        return lhs.tag == rhs.tag && lhs.id == rhs.id
     }
     private(set) var tag: SelectedType
+    fileprivate(set) var id: String?
     fileprivate(set) var view: AnyView
     fileprivate(set) var index: Int
 
-    var id: SelectedType { tag }
+//    var id: SelectedType { tag }
+//    var id: SelectedType { tag }
 
-    fileprivate init(tag: SelectedType, index: Int, view: AnyView) {
+    fileprivate init(tag: SelectedType, id: String?, index: Int, view: AnyView) {
         self.tag = tag
+        self.id = id
         self.index = index
         self.view = view
     }
@@ -127,19 +129,21 @@ public class PagerSettings<SelectionType>: ObservableObject where SelectionType:
     @Published private(set) var itemsOrderedByIndex = [SelectionType]()
 
     private func recalculateTransition() {
-        let indexAndPercentage = -contentOffset / width
+        guard width > 0 else { return }
+        let indexAndPercentage = width == 0 ? 0 : -contentOffset / width
         let percentage = (indexAndPercentage + 1).truncatingRemainder(dividingBy: 1)
         let lowIndex = Int(floor(indexAndPercentage))
         transition = TransitionProgress(from: itemsOrderedByIndex[safe: lowIndex], to: itemsOrderedByIndex[safe: lowIndex+1], percentage: percentage)
     }
 
-    func createOrUpdate<TabView: View>(tag: SelectionType, index: Int, view: TabView) {
+    func createOrUpdate<TabView: View>(tag: SelectionType, id: String?, index: Int, view: TabView) {
         if var dataItem = items[tag] {
+            dataItem.id = id
             dataItem.index = index
             dataItem.view = AnyView(view)
             items[tag] = dataItem
         } else {
-            items[tag] = DataItem(tag: tag, index: index, view: AnyView(view))
+            items[tag] = DataItem(tag: tag, id: id, index: index, view: AnyView(view))
         }
     }
 

diff --git a/Sources/PagerStyle.swift b/Sources/PagerStyle.swift
@@ -44,11 +44,13 @@ extension PagerStyle where Self == SegmentedControlStyle {
     public static func segmentedControl(placedInToolbar: Bool = false,
                                         pagerAnimationOnTap: Animation? = DefaultPagerAnimation.onTap,
                                         pagerAnimationOnSwipe: Animation? = DefaultPagerAnimation.onSwipe,
+                                        navBarID: String? = nil,
                                         backgroundColor: Color = .white,
                                         padding: EdgeInsets = EdgeInsets(top: 0, leading: 10, bottom: 0, trailing: 10)) -> SegmentedControlStyle {
         return SegmentedControlStyle(placedInToolbar: placedInToolbar,
                                      pagerAnimationOnTap: pagerAnimationOnTap,
                                      pagerAnimationOnSwipe: pagerAnimationOnSwipe,
+                                     navBarID: navBarID,
                                      backgroundColor: backgroundColor,
                                      padding: padding)
     }
@@ -101,21 +103,23 @@ public struct SegmentedControlStyle: PagerStyle {
     public var placedInToolbar: Bool
     public var pagerAnimationOnTap: Animation?
     public var pagerAnimationOnSwipe: Animation?
+    public var navBarID: String? = nil
     public var backgroundColor: Color
     public var padding: EdgeInsets = EdgeInsets(top: 0, leading: 0, bottom: 0, trailing: 0)
 
     public init(placedInToolbar: Bool = false,
                 pagerAnimationOnTap: Animation? = DefaultPagerAnimation.onTap,
                 pagerAnimationOnSwipe: Animation? = DefaultPagerAnimation.onSwipe,
+                navBarID: String? = nil,
                 backgroundColor: Color = .white,
                 padding: EdgeInsets = EdgeInsets(top: 0, leading: 0, bottom: 0, trailing: 0)) {
         self.backgroundColor = backgroundColor
+        self.navBarID = navBarID
         self.placedInToolbar = placedInToolbar
         self.padding = padding
         self.pagerAnimationOnTap = pagerAnimationOnTap
         self.pagerAnimationOnSwipe = pagerAnimationOnSwipe
     }
-
 }
 
 public struct BarStyle: PagerWithIndicatorStyle {

diff --git a/Sources/PagerTabItemModifier.swift b/Sources/PagerTabItemModifier.swift
@@ -11,9 +11,11 @@ struct PagerTabItemModifier<SelectionType, NavTabView>: ViewModifier where Selec
 
     let navTabView: () -> NavTabView
     let tag: SelectionType
-
-    init(tag: SelectionType, navTabView: @escaping () -> NavTabView) {
+    var id: String?
+
+    init(tag: SelectionType, id: String? = nil, navTabView: @escaping () -> NavTabView) {
         self.tag = tag
+        self.id = id
         self.navTabView = navTabView
     }
 
@@ -23,16 +25,24 @@ struct PagerTabItemModifier<SelectionType, NavTabView>: ViewModifier where Selec
                 .onAppear {
                     let frame = geometryProxy.frame(in: .named("PagerViewScrollView"))
                     index = Int(round(frame.minX / frame.width))
-                    pagerSettings.createOrUpdate(tag: tag, index: index, view: navTabView())
-                }.onDisappear {
+                    pagerSettings.createOrUpdate(tag: tag, id: id, index: index, view: navTabView())
+                }
+                .onDisappear {
                     pagerSettings.remove(tag: tag)
                 }
                 .onChange(of: geometryProxy.frame(in: .named("PagerViewScrollView"))) { newFrame in
                     index = Int(round(newFrame.minX / newFrame.width))
                 }
                 .onChange(of: index) { newIndex in
-                    pagerSettings.createOrUpdate(tag: tag, index: newIndex, view: navTabView())
+                    pagerSettings.createOrUpdate(tag: tag, id: id, index: newIndex, view: navTabView())
+                }
+                .onChange(of: id) { newID in
+                    pagerSettings.createOrUpdate(tag: tag, id: newID, index: index, view: navTabView())
+                }
+                .task {
+                    pagerSettings.createOrUpdate(tag: tag, id: id, index: index, view: navTabView())
                 }
+                .id(id)
         }
     }