Always popover

Sources/BSWInterfaceKit/SwiftUI/Extensions/SwiftUI+AlwaysPopover.swift

@@ -0,0 +1,99 @@
+import SwiftUI
+
+extension View {
+    func alwaysPopover<Content: View, Value: Identifiable>(id: Value.ID, isPresented: Binding<Value?>, @ViewBuilder content: @escaping () -> Content) -> some View {
+        self.modifier(AlwaysPopoverModifier(id: id, isPresented: isPresented, contentBlock: content))
+    }
+
+}
+
+private struct AlwaysPopoverModifier<PopoverContent: View, Value: Identifiable>: ViewModifier {
+
+    let id: Value.ID
+    let isPresented: Binding<Value?>
+    let contentBlock: () -> PopoverContent
+    @State private var anchorView = UIView()
+
+    func body(content: Content) -> some View {
+        if let value = isPresented.wrappedValue, value.id == id {
+            presentPopover(value: value)
+        }
+
+        return content
+            .background(InternalAnchorView(uiView: anchorView))
+    }
+
+    func presentPopover(value: Value) {
+        let contentController = ContentViewController(
+            // Ensures the text wraps to fit the content
+            rootView: contentBlock()
+                .fixedSize(horizontal: false, vertical: true),
+            isPresented: isPresented
+        )
+        contentController.modalPresentationStyle = .popover
+
+        let view = anchorView
+        guard let popover = contentController.popoverPresentationController else { return }
+        popover.sourceView = view
+        popover.sourceRect = view.bounds
+        popover.delegate = contentController
+
+        guard let sourceVC = view.next() as UIViewController? else { return }
+        sourceVC.present(contentController, animated: true)
+    }
+
+    struct InternalAnchorView: UIViewRepresentable {
+        let uiView: UIView
+
+        func makeUIView(context: Self.Context) -> UIView {
+            uiView
+        }
+
+        func updateUIView(_ uiView: UIView, context: Self.Context) { }
+    }
+
+    class ContentViewController<FinalView: View>: UIHostingController<FinalView>, UIPopoverPresentationControllerDelegate {
+
+        var isPresented: Binding<Value?>
+
+        init(rootView: FinalView, isPresented: Binding<Value?>) {
+            self.isPresented = isPresented
+            super.init(rootView: rootView)
+        }
+
+        @preconcurrency required dynamic init?(coder aDecoder: NSCoder) {
+            fatalError("init(coder:) has not been implemented")
+        }
+
+        override func viewDidLoad() {
+            super.viewDidLoad()
+            updatePreferredContentSize()
+        }
+
+        override func viewDidLayoutSubviews() {
+            super.viewDidLayoutSubviews()
+            updatePreferredContentSize()
+        }
+
+        private let MaxWidth: CGFloat = 320
+
+        private func updatePreferredContentSize() {
+            let size = view.systemLayoutSizeFitting(
+                CGSize(width: MaxWidth, height: UIView.layoutFittingCompressedSize.height),
+                withHorizontalFittingPriority: .required,
+                verticalFittingPriority: .fittingSizeLevel
+            )
+            preferredContentSize = size
+        }
+
+        // MARK: UIPopoverPresentationControllerDelegate
+
+        func adaptivePresentationStyle(for controller: UIPresentationController, traitCollection: UITraitCollection) -> UIModalPresentationStyle {
+            return .none
+        }
+
+        func presentationControllerDidDismiss(_ presentationController: UIPresentationController) {
+            self.isPresented.wrappedValue = nil
+        }
+    }
+}