Fitting size with axis

Examples/Example-iOS/Sources/Kyoto/KyotoViewController.swift

@@ -46,4 +46,11 @@ final class KyotoViewController: UIViewController {
             })
         }
     }
+
+    override func viewDidLayoutSubviews() {
+        super.viewDidLayoutSubviews()
+
+        // This solves sizing bug in MagazineLayout.
+        collectionView.performBatchUpdates(nil)
+    }
 }

Sources/ComponentWrapper/ComponentWrapping.swift

@@ -143,16 +143,3 @@ public extension ComponentWrapping {
         wrapped.contentDidEndDisplay(content)
     }
 }
-
-#if canImport(SwiftUI) && canImport(Combine)
-
-import SwiftUI
-
-@available(iOS 13.0, *)
-public extension ComponentWrapping where Wrapped: View {
-    var body: some View {
-        wrapped.body
-    }
-}
-
-#endif

Sources/SwiftUISupport/ComponentSwiftUISupport.swift

@@ -6,26 +6,32 @@ import SwiftUI
 public extension Component where Self: View {
     /// Declares the content and behavior of this view.
     var body: some View {
-        ComponentView(self)
+        sizeFitting(.vertical)
+    }
+
+    func sizeFitting(_ axis: Axis? = nil) -> some Component & View {
+        SizeFittingComponentView(self, axis: axis)
     }
 }
 
 @available(iOS 13.0, *)
-private struct ComponentView<C: Component>: View {
-    var component: C
-    var proxy = ComponentViewProxy()
+private struct SizeFittingComponentView<Wrapped: Component>: View, ComponentWrapping {
+    var wrapped: Wrapped
+    var axis: Axis?
 
-    @State var bounds: CGRect?
+    private var proxy = ComponentViewProxy()
+    @State private var bounds: CGRect?
 
-    init(_ component: C) {
-        self.component = component
+    public init(_ wrapped: Wrapped, axis: Axis?) {
+        self.wrapped = wrapped
+        self.axis = axis
     }
 
     var body: some View {
-        let idealSize = self.idealSize()
-        return ComponentRepresenting(component: component, proxy: proxy)
-            .frame(idealWidth: idealSize?.width)
-            .frame(height: idealSize?.height)
+        let preferredSize = self.preferredSize()
+        return ComponentRepresenting(component: AnyComponent(wrapped), proxy: proxy)
+            .frame(idealWidth: preferredSize.idealWidth, idealHeight: preferredSize.idealHeight)
+            .frame(width: preferredSize.fixedWidth, height: preferredSize.fixedHeight)
             .clipped()
             .onAppear { self.proxy.uiView?.contentWillDisplay() }
             .onDisappear { self.proxy.uiView?.contentDidEndDisplay() }
@@ -37,24 +43,59 @@ private struct ComponentView<C: Component>: View {
 }
 
 @available(iOS 13.0, *)
-extension ComponentView {
-    func idealSize() -> CGSize? {
+private extension SizeFittingComponentView {
+    struct Size {
+        var idealWidth: CGFloat?
+        var idealHeight: CGFloat?
+        var fixedWidth: CGFloat?
+        var fixedHeight: CGFloat?
+    }
+
+    func preferredSize() -> Size {
         guard let bounds = bounds else {
-            return nil
+            return Size()
         }
 
-        if let referenceSize = component.referenceSize(in: bounds) {
-            return referenceSize
-        }
-        else {
-            return proxy.uiView?.systemLayoutSizeFitting(
+        let referenceSize = wrapped.referenceSize(in: bounds)
+
+        switch axis {
+        case .none:
+            let size = referenceSize ?? proxy.uiView?.systemLayoutSizeFitting(UIView.layoutFittingCompressedSize)
+
+            return Size(
+                fixedWidth: size?.width,
+                fixedHeight: size?.height
+            )
+
+        case .horizontal:
+            let size = referenceSize ?? proxy.uiView?.systemLayoutSizeFitting(
+                CGSize(
+                    width: UIView.layoutFittingCompressedSize.width,
+                    height: bounds.size.height
+                ),
+                withHorizontalFittingPriority: .fittingSizeLevel,
+                verticalFittingPriority: .required
+            )
+
+            return Size(
+                idealHeight: size?.height,
+                fixedWidth: size?.width
+            )
+
+        case .vertical:
+            let size = referenceSize ?? proxy.uiView?.systemLayoutSizeFitting(
                 CGSize(
                     width: bounds.size.width,
                     height: UIView.layoutFittingCompressedSize.height
                 ),
                 withHorizontalFittingPriority: .required,
                 verticalFittingPriority: .fittingSizeLevel
             )
+
+            return Size(
+                idealWidth: size?.width,
+                fixedHeight: size?.height
+            )
         }
     }
 }
@@ -63,8 +104,8 @@ private struct BoundsPreferenceKey: PreferenceKey {
     static func reduce(value: inout CGRect?, nextValue: () -> CGRect?) {}
 }
 
-private struct ComponentRepresenting<C: Component>: UIViewRepresentable {
-    var component: C
+private struct ComponentRepresenting: UIViewRepresentable {
+    var component: AnyComponent
     var proxy: ComponentViewProxy
 
     func makeUIView(context: Context) -> UIComponentView {
@@ -73,7 +114,7 @@ private struct ComponentRepresenting<C: Component>: UIViewRepresentable {
 
     func updateUIView(_ uiView: UIComponentView, context: Context) {
         proxy.uiView = uiView
-        uiView.render(component: AnyComponent(component))
+        uiView.render(component: component)
     }
 }