Merge pull request '[fix] LCENavigationView: remove phantom glass button, center title safely' (#11) from fix/navigation/glass-duplicate-button into main

Reviewed-on: #11

Sources/LCEssentials/SwiftUI/LCENavigationView.swift

@@ -42,13 +42,46 @@ class LCENavigationState: ObservableObject {
     
     /// A boolean value that controls the visibility of the navigation bar.
     @Published var hideNavigationBar: Bool = false
-    
+
     /// The title view of the navigation bar.
     @Published var title: (any View) = Text("")
     /// The subtitle view of the navigation bar.
     @Published var subTitle: (any View) = Text("")
     /// The background color of the navigation bar.
     @Published var navigationBarBackgroundColor: Color = .clear
+
+    /// Whether a left button was actually configured via `setLeftButton`.
+    @Published var hasLeftButton: Bool = false
+    /// Whether a right button was actually configured via `setRightButton`.
+    @Published var hasRightButton: Bool = false
+    /// Whether buttons should opt into the system Liquid Glass button style (iOS 26+). Off by default.
+    @Published var useGlassButtons: Bool = false
+}
+
+/// `PreferenceKey` used to measure the widest side button so the title can be padded symmetrically and stay centered without overlapping either button.
+@available(iOS 15, *)
+private struct LCENavButtonWidthPreferenceKey: PreferenceKey {
+    static var defaultValue: CGFloat { 0 }
+    static func reduce(value: inout CGFloat, nextValue: () -> CGFloat) {
+        value = max(value, nextValue())
+    }
+}
+
+@available(iOS 15, *)
+private extension View {
+    /// Applies `.glass` button style on iOS 26+ when enabled, otherwise falls back to `.plain` — the navigation bar is not designed around glass, but stays opt-in ready.
+    @ViewBuilder
+    func lce_applyGlassIfEnabled(_ enabled: Bool) -> some View {
+        if enabled {
+            if #available(iOS 26.0, *) {
+                self.buttonStyle(.glass)
+            } else {
+                self.buttonStyle(.plain)
+            }
+        } else {
+            self.buttonStyle(.plain)
+        }
+    }
 }
 
 /// `LCENavigationView` is a SwiftUI `View` that provides a customizable navigation bar.
@@ -60,7 +93,10 @@ public struct LCENavigationView<Content: View>: View {
     
     /// The content view displayed below the navigation bar.
     let content: Content
-    
+
+    /// The measured width of the widest side button, used to pad the title so it never overlaps either button.
+    @State private var maxButtonWidth: CGFloat = 0
+
     /// Initializes a new `LCENavigationView` instance.
     /// - Parameters:
     ///   - title: The title view for the navigation bar. Defaults to an empty `Text`.
@@ -92,20 +128,31 @@ public struct LCENavigationView<Content: View>: View {
 
     /// The private `NavigationBarView` that lays out the navigation bar components.
     private var NavigationBarView: some View {
-        HStack {
+        ZStack {
-            NavLeftButton
-            Spacer()
             TitleView
-            Spacer()
+                .padding(.horizontal, maxButtonWidth)
-            NavRightButton
+                .lineLimit(1)
+                .minimumScaleFactor(0.7)
+                .frame(maxWidth: .infinity)
+
+            HStack {
+                if state.hasLeftButton {
+                    NavLeftButton
+                }
+                Spacer()
+                if state.hasRightButton {
+                    NavRightButton
+                }
+            }
         }
         .font(.headline)
         .padding()
         .background {
             state.navigationBarBackgroundColor.ignoresSafeArea(edges: .top)
         }
+        .onPreferenceChange(LCENavButtonWidthPreferenceKey.self) { maxButtonWidth = $0 }
     }
-    
+
     /// The private `TitleView` that displays the title and subtitle.
     private var TitleView: some View {
         VStack {
@@ -115,8 +162,8 @@ public struct LCENavigationView<Content: View>: View {
             }
         }
     }
-    
+
-    /// The private `NavLeftButton` view.
+    /// The private `NavLeftButton` view. Only rendered when `setLeftButton` was actually called — never a hidden placeholder.
     private var NavLeftButton: some View {
         Button(action: state.leftButtonAction) {
             HStack {
@@ -126,9 +173,15 @@ public struct LCENavigationView<Content: View>: View {
                 state.leftButtonText
             }
         }
+        .lce_applyGlassIfEnabled(state.useGlassButtons)
+        .background(
+            GeometryReader { proxy in
+                Color.clear.preference(key: LCENavButtonWidthPreferenceKey.self, value: proxy.size.width)
+            }
+        )
     }
-    
+
-    /// The private `NavRightButton` view.
+    /// The private `NavRightButton` view. Only rendered when `setRightButton` was actually called — never a hidden placeholder.
     private var NavRightButton: some View {
         Button(action: state.rightButtonAction) {
             HStack {
@@ -138,6 +191,12 @@ public struct LCENavigationView<Content: View>: View {
                 }
             }
         }
+        .lce_applyGlassIfEnabled(state.useGlassButtons)
+        .background(
+            GeometryReader { proxy in
+                Color.clear.preference(key: LCENavButtonWidthPreferenceKey.self, value: proxy.size.width)
+            }
+        )
     }
     
     /// Sets the configuration for the right button of the navigation bar.
@@ -158,14 +217,8 @@ public struct LCENavigationView<Content: View>: View {
         }
         state.rightButtonText = text
         state.rightButtonAction = action
-        
+        state.hasRightButton = true
-        if let string = state.leftButtonText.string, string.isEmpty {
+
-            state.leftButtonText = text.foregroundColor(.clear)
-        }
-        if state.leftButtonImage == nil {
-            state.leftButtonImage = image?.foregroundColor(.clear) as? AnyView
-        }
-        
         return self
     }
     
@@ -187,14 +240,17 @@ public struct LCENavigationView<Content: View>: View {
         }
         state.leftButtonText = text
         state.leftButtonAction = action
-        
+        state.hasLeftButton = true
-        if let string = state.rightButtonText.string, string.isEmpty {
+
-            state.rightButtonText = text.foregroundColor(.clear)
+        return self
-        }
+    }
-        if state.rightButtonImage == nil {
+
-            state.rightButtonImage = image?.foregroundColor(.clear) as? AnyView
+    /// Opts the navigation bar's buttons into the system Liquid Glass `.glass` button style on iOS 26+.
-        }
+    /// The navigation bar is designed as a plain, non-glass component by default; call this to enable glass explicitly.
-        
+    /// - Parameter enabled: Whether buttons should use the glass style.
+    /// - Returns: The `LCENavigationView` instance for chaining.
+    public func setGlassButtonsEnabled(_ enabled: Bool) -> LCENavigationView {
+        state.useGlassButtons = enabled
         return self
     }
     
@@ -229,101 +285,6 @@ public struct LCENavigationView<Content: View>: View {
     }
 }
 
-/// Extension to `FormatStyle` to format any value as a string.
-@available(iOS 15.0, *)
-extension FormatStyle {
-    /// Formats an input value if it matches the `FormatInput` type.
-    /// - Parameter value: The value to format as `Any`.
-    /// - Returns: The formatted output, or `nil` if the value type does not match.
-    func format(any value: Any) -> FormatOutput? {
-        if let v = value as? FormatInput {
-            return format(v)
-        }
-        return nil
-    }
-}
-
-/// Extension to `LocalizedStringKey` to resolve localized strings.
-@available(iOS 15.0, *)
-extension LocalizedStringKey {
-    /// Resolves the localized string key into a `String`.
-    /// - Returns: The resolved string, or `nil` if resolution fails.
-    var resolved: String? {
-        let mirror = Mirror(reflecting: self)
-        guard let key = mirror.descendant("key") as? String else {
-            return nil
-        }
-
-        guard let args = mirror.descendant("arguments") as? [Any] else {
-            return nil
-        }
-
-        let values = args.map { arg -> Any? in
-            let mirror = Mirror(reflecting: arg)
-            if let value = mirror.descendant("storage", "value", ".0") {
-                return value
-            }
-
-            guard let format = mirror.descendant("storage", "formatStyleValue", "format") as? any FormatStyle,
-                  let input = mirror.descendant("storage", "formatStyleValue", "input") else {
-                return nil
-            }
-
-            return format.format(any: input)
-        }
-
-        let va = values.compactMap { arg -> CVarArg? in
-            switch arg {
-            case let i as Int:      return i
-            case let i as Int64:    return i
-            case let i as Int8:     return i
-            case let i as Int16:    return i
-            case let i as Int32:    return i
-            case let u as UInt:     return u
-            case let u as UInt64:   return u
-            case let u as UInt8:    return u
-            case let u as UInt16:   return u
-            case let u as UInt32:   return u
-            case let f as Float:    return f
-            case let f as CGFloat:  return f
-            case let d as Double:   return d
-            case let o as NSObject: return o
-            default:                return nil
-            }
-        }
-
-        if va.count != values.count {
-            return nil
-        }
-
-        return String.localizedStringWithFormat(key, va)
-    }
-}
-
-/// Extension to `Text` to retrieve its string content.
-@available(iOS 15.0, *)
-extension Text {
-    /// Returns the string representation of the `Text` view.
-    /// - Returns: The string content, or `nil` if it cannot be extracted.
-    var string: String? {
-        let mirror = Mirror(reflecting: self)
-        if let s = mirror.descendant("storage", "verbatim") as? String {
-            return s
-        } else if let attrStr = mirror.descendant("storage", "anyTextStorage", "str") as? AttributedString {
-            return String(attrStr.characters)
-        } else if let key = mirror.descendant("storage", "anyTextStorage", "key") as? LocalizedStringKey {
-            return key.resolved
-        } else if let format = mirror.descendant("storage", "anyTextStorage", "storage", "format") as? any FormatStyle,
-                  let input = mirror.descendant("storage", "anyTextStorage", "storage", "input") {
-            return format.format(any: input) as? String
-        } else if let formatter = mirror.descendant("storage", "anyTextStorage", "formatter") as? Formatter,
-                  let object = mirror.descendant("storage", "anyTextStorage", "object") {
-            return formatter.string(for: object)
-        }
-        return nil
-    }
-}
-
 //@available(iOS 15.0, *)
 //struct LCENavigationView_Previews: PreviewProvider {
 //    static var previews: some View {