fix tvOS (and visionOS) compilation error

Author: MiaKoring

Examples/Sources/WindowingExample/WindowingApp.swift

@@ -219,7 +219,7 @@ struct WindowingApp: App {
                 }
             }
         }
-        #if !os(iOS)
+        #if !os(iOS) && !os(tvOS)
             WindowGroup("Secondary window") {
                 #hotReloadable {
                     Text("This a secondary window!")

Sources/SwiftCrossUI/Views/Modifiers/PresentationModifiers.swift

@@ -4,7 +4,7 @@ extension View {
     /// This modifier only affects the sheet presentation itself.
     /// It allows users to resize the sheet to different predefined heights.
     ///
-    /// - Supported platforms: iOS 15+ (ignored on unsupported platforms)
+    /// - Supported platforms: iOS & Mac Catalyst 15+ (ignored on unsupported platforms)
     /// - `.fraction` and `.height` fall back to `.medium` on iOS 15 and earlier
     ///
     /// - Parameter detents: A set of detents that the sheet can be resized to.
@@ -18,7 +18,7 @@ extension View {
     /// This modifier only affects the sheet presentation itself.
     /// It does not affect the content's corner radius.
     ///
-    /// - Supported platforms: iOS 15+, Gtk4 (ignored on unsupported platforms)
+    /// - Supported platforms: iOS & Mac Catalyst 15+, Gtk4 (ignored on unsupported platforms)
     ///
     /// - Parameter radius: The corner radius in points.
     /// - Returns: A view with the presentationCornerRadius preference set.
@@ -30,7 +30,7 @@ extension View {
     ///
     /// This modifier only affects the sheet presentation itself.
     ///
-    /// - Supported platforms: iOS 15+ (ignored on unsupported platforms)
+    /// - Supported platforms: iOS & Mac Catalyst 15+ (ignored on unsupported platforms)
     ///
     /// - Parameter visibility: visible or hidden
     /// - Returns: A view with the presentationDragIndicatorVisibility preference set.

Sources/SwiftCrossUI/Views/Modifiers/SheetModifier.swift

@@ -1,5 +1,7 @@
 extension View {
     /// Presents a conditional modal overlay. `onDismiss` gets invoked when the sheet is dismissed.
+    ///
+    /// Internal modalPresentationStyle falls back to .overFullScreen (non-opaque) on tvOS 18 and earlier.
     public func sheet<SheetContent: View>(
         isPresented: Binding<Bool>, onDismiss: (() -> Void)? = nil,
         @ViewBuilder content: @escaping () -> SheetContent

Sources/UIKitBackend/UIKitBackend+Sheet.swift

@@ -6,7 +6,15 @@ extension UIKitBackend {
 
     public func createSheet(content: Widget) -> CustomSheet {
         let sheet = CustomSheet()
-        sheet.modalPresentationStyle = .formSheet
+        #if !os(tvOS)
+            sheet.modalPresentationStyle = .formSheet
+        #else
+            if #available(tvOS 26.0, *) {
+                sheet.modalPresentationStyle = .formSheet
+            } else {
+                sheet.modalPresentationStyle = .overFullScreen
+            }
+        #endif
         sheet.view = content.view
         return sheet
     }
@@ -52,7 +60,7 @@ extension UIKitBackend {
 
     public func setPresentationDetents(of sheet: CustomSheet, to detents: [PresentationDetent]) {
         if #available(iOS 15.0, macCatalyst 15.0, *) {
-            #if !os(visionOS)
+            #if !os(tvOS) && !os(visionOS)
                 if let sheetPresentation = sheet.sheetPresentationController {
                     sheetPresentation.detents = detents.map {
                         switch $0 {
@@ -85,23 +93,23 @@ extension UIKitBackend {
         } else {
             #if DEBUG
                 print(
-                    "your current OS Version doesn't support variable sheet heights. Setting presentationDetents is only available from iOS 15.0"
+                    "Your current OS Version doesn't support variable sheet heights. Setting presentationDetents is only available from iOS 15.0. tvOS and visionOS are not supported."
                 )
             #endif
         }
     }
 
     public func setPresentationCornerRadius(of sheet: CustomSheet, to radius: Double) {
         if #available(iOS 15.0, *) {
-            #if !os(visionOS)
+            #if !os(tvOS) && !os(visionOS)
                 if let sheetController = sheet.sheetPresentationController {
                     sheetController.preferredCornerRadius = radius
                 }
             #endif
         } else {
             #if DEBUG
                 print(
-                    "your current OS Version doesn't support variable sheet corner radii. Setting them is only available from iOS 15.0"
+                    "Your current OS Version doesn't support variable sheet corner radii. Setting them is only available from iOS 15.0. tvOS and visionOS are not supported."
                 )
             #endif
         }
@@ -111,15 +119,15 @@ extension UIKitBackend {
         of sheet: Sheet, to visibility: Visibility
     ) {
         if #available(iOS 15.0, *) {
-            #if !os(visionOS)
+            #if !os(tvOS) && !os(visionOS)
                 if let sheetController = sheet.sheetPresentationController {
                     sheetController.prefersGrabberVisible = visibility == .visible ? true : false
                 }
             #endif
         } else {
             #if DEBUG
                 print(
-                    "Your current OS Version doesn't support setting sheet drag indicator visibility. Setting this is only available from iOS 15.0"
+                    "Your current OS Version doesn't support setting sheet drag indicator visibility. Setting this is only available from iOS 15.0. tvOS and visionOS are not supported."
                 )
             #endif
         }