Paywalls: fix template 5 scrolling on iOS 15 (#3608)

The previous implementation used `ScrollableIfNecessaryModifier` which
is a hacky work around for iOS 15 not having `ViewThatFits`.

To work around issues with that, specific to template 5, this new
approach avoids the "if necessary" part on iOS 15 which removes the
problematic usage of `GeometryReader`.

RevenueCatUI/Modifiers/ViewExtensions.swift

@@ -11,6 +11,8 @@
 //
 //  Created by Nacho Soto on 7/13/23.
 
+// swiftlint:disable file_length
+
 import Foundation
 import SwiftUI
 
@@ -53,7 +55,7 @@ extension View {
 
 // MARK: - Scrolling
 
-@available(iOS 13.0, tvOS 13.0, macOS 10.15, watchOS 6.2, *)
+@available(iOS 15.0, macOS 12.0, tvOS 15.0, watchOS 8.0, *)
 extension View {
 
     @ViewBuilder
@@ -83,7 +85,6 @@ extension View {
         #endif
     }
 
-    @available(iOS 15.0, macOS 12.0, tvOS 15.0, watchOS 8.0, *)
     @ViewBuilder
     func scrollableIfNecessary(_ axis: Axis = .vertical, enabled: Bool = true) -> some View {
         if enabled {
@@ -102,6 +103,48 @@ extension View {
             self
         }
     }
+
+    /// Equivalent to `scrollableIfNecessary` except that it's always scrollable on iOS 15
+    /// to work around issues with that iOS 15 implementation in some instances.
+    @ViewBuilder
+    func scrollableIfNecessaryWhenAvailable(_ axis: Axis = .vertical, enabled: Bool = true) -> some View {
+        if enabled {
+            if #available(iOS 16.0, macOS 13.0, tvOS 16.0, watchOS 9.0, *) {
+                ViewThatFits(in: axis.scrollViewAxis) {
+                    self
+
+                    ScrollView(axis.scrollViewAxis) {
+                        self
+                    }
+                }
+            } else {
+                self
+                    .centeredContent(axis)
+                    .scrollable(if: enabled)
+            }
+        } else {
+            self
+        }
+    }
+
+    @ViewBuilder
+    fileprivate func centeredContent(_ axis: Axis) -> some View {
+        switch axis {
+        case .horizontal:
+            HStack {
+                Spacer()
+                self
+                Spacer()
+            }
+        case .vertical:
+            VStack {
+                Spacer()
+                self
+                Spacer()
+            }
+        }
+    }
+
 }
 
 // MARK: - Padding
@@ -163,7 +206,8 @@ private struct ScrollableIfNecessaryModifier: ViewModifier {
 
     func body(content: Content) -> some View {
         GeometryReader { geometry in
-            self.centeredContent(content)
+            content
+                .centeredContent(self.axis)
                 .background(
                     GeometryReader { contentGeometry in
                         Color.clear
@@ -181,24 +225,6 @@ private struct ScrollableIfNecessaryModifier: ViewModifier {
         .scrollable(self.axis.scrollViewAxis, if: self.overflowing)
     }
 
-    @ViewBuilder
-    private func centeredContent(_ content: Content) -> some View {
-        switch self.axis {
-        case .horizontal:
-            HStack {
-                Spacer()
-                content
-                Spacer()
-            }
-        case .vertical:
-            VStack {
-                Spacer()
-                content
-                Spacer()
-            }
-        }
-    }
-
 }
 
 // MARK: - Size changes

RevenueCatUI/Templates/Template5View.swift

@@ -77,11 +77,11 @@ struct Template5View: TemplateViewType {
                     self.features
                 }
                 .padding(.top, self.defaultVerticalPaddingLength)
-                .scrollableIfNecessary()
+                .scrollableIfNecessaryWhenAvailable()
 
                 self.packages
                     .padding(.top, self.defaultVerticalPaddingLength)
-                    .scrollableIfNecessary()
+                    .scrollableIfNecessaryWhenAvailable()
             }
 
             Spacer()
@@ -108,7 +108,7 @@ struct Template5View: TemplateViewType {
                         // Compensate for additional padding on condensed mode + iPad
                         : self.defaultVerticalPaddingLength.map { $0 * -1 }
                     )
-                    .scrollableIfNecessary(enabled: self.configuration.mode.isFullScreen)
+                    .scrollableIfNecessaryWhenAvailable(enabled: self.configuration.mode.isFullScreen)
             }
 
             if self.configuration.mode.shouldDisplayInlineOfferDetails(displayingAllPlans: self.displayingAllPlans) {

Tests/purchases-ios-snapshots-commit

@@ -1 +1 @@
-07f89b6e14d285d8b4534af32ba2f25935105a18
+04bf0f2f07f042f642f50df0c876e805120c6e71