Add window behavior modifiers

Examples/Sources/WindowingExample/WindowingApp.swift

@@ -161,9 +161,12 @@ struct SheetDemo: View {
 @HotReloadable
 struct WindowingApp: App {
     @State var title = "My window"
-    @State var resizable = false
+    @State var resizable = true
     @State var isAlertSceneShown = false
     @State var toggle = false
+    @State var enforceMaxSize = true
+    @State var closable = true
+    @State var minimizable = true
 
     var body: some Scene {
         WindowGroup(title) {
@@ -174,9 +177,12 @@ struct WindowingApp: App {
                         TextField("My window", text: $title)
                     }
 
-                    Button(resizable ? "Disable resizing" : "Enable resizing") {
-                        resizable = !resizable
-                    }
+                    Toggle("Enable resizing", isOn: $resizable)
+                        .windowResizeBehavior(resizable ? .enabled : .disabled)
+                    Toggle("Enable closing", isOn: $closable)
+                        .windowDismissBehavior(closable ? .enabled : .disabled)
+                    Toggle("Enable minimizing", isOn: $minimizable)
+                        .preferredWindowMinimizeBehavior(minimizable ? .enabled : .disabled)
 
                     Image(Bundle.module.bundleURL.appendingPathComponent("Banner.png"))
                         .resizable()
@@ -204,7 +210,6 @@ struct WindowingApp: App {
             }
         }
         .defaultSize(width: 500, height: 500)
-        .windowResizability(resizable ? .contentMinSize : .contentSize)
         .commands {
             CommandMenu("Demo menu") {
                 Button("Menu item") {}
@@ -223,12 +228,17 @@ struct WindowingApp: App {
         #if !(os(iOS) || os(tvOS) || os(Windows))
             WindowGroup("Secondary window") {
                 #hotReloadable {
-                    Text("This a secondary window!")
-                        .padding(10)
+                    VStack {
+                        Text("This a secondary window!")
+
+                        Toggle("Enforce max size", isOn: $enforceMaxSize)
+                            .toggleStyle(.checkbox)
+                    }
+                    .padding(10)
                 }
             }
             .defaultSize(width: 200, height: 200)
-            .windowResizability(.contentMinSize)
+            .windowResizability(enforceMaxSize ? .contentSize : .contentMinSize)
 
             WindowGroup("Tertiary window") {
                 #hotReloadable {
@@ -237,7 +247,6 @@ struct WindowingApp: App {
                 }
             }
             .defaultSize(width: 200, height: 200)
-            .windowResizability(.contentMinSize)
         #endif
     }
 }

Sources/AppKitBackend/AppKitBackend.swift

@@ -87,9 +87,18 @@ public final class AppKitBackend: AppBackend {
         window.setContentSize(NSSize(width: newSize.x, height: newSize.y))
     }
 
-    public func setMinimumSize(ofWindow window: Window, to minimumSize: SIMD2<Int>) {
-        window.contentMinSize.width = CGFloat(minimumSize.x)
-        window.contentMinSize.height = CGFloat(minimumSize.y)
+    public func setSizeLimits(
+        ofWindow window: Window,
+        minimum minimumSize: SIMD2<Int>,
+        maximum maximumSize: SIMD2<Int>?
+    ) {
+        window.contentMinSize = CGSize(width: minimumSize.x, height: minimumSize.y)
+        window.contentMaxSize =
+            if let maximumSize {
+                CGSize(width: maximumSize.x, height: maximumSize.y)
+            } else {
+                CGSize(width: Double.infinity, height: .infinity)
+            }
     }
 
     public func setResizeHandler(
@@ -103,7 +112,24 @@ public final class AppKitBackend: AppBackend {
         window.title = title
     }
 
-    public func setResizability(ofWindow window: Window, to resizable: Bool) {
+    public func setBehaviors(
+        ofWindow window: Window,
+        closable: Bool,
+        minimizable: Bool,
+        resizable: Bool
+    ) {
+        if closable {
+            window.styleMask.insert(.closable)
+        } else {
+            window.styleMask.remove(.closable)
+        }
+
+        if minimizable {
+            window.styleMask.insert(.miniaturizable)
+        } else {
+            window.styleMask.remove(.miniaturizable)
+        }
+
         if resizable {
             window.styleMask.insert(.resizable)
         } else {

Sources/DummyBackend/DummyBackend.swift

@@ -7,8 +7,11 @@ public final class DummyBackend: AppBackend {
 
         public var size: SIMD2<Int>
         public var minimumSize: SIMD2<Int> = .zero
+        public var maximumSize: SIMD2<Int>?
         public var title = "Window"
         public var resizable = true
+        public var closable = true
+        public var minimizable = true
         public var content: Widget?
         public var resizeHandler: ((SIMD2<Int>) -> Void)?
 
@@ -264,7 +267,14 @@ public final class DummyBackend: AppBackend {
         window.title = title
     }
 
-    public func setResizability(ofWindow window: Window, to resizable: Bool) {
+    public func setBehaviors(
+        ofWindow window: Window,
+        closable: Bool,
+        minimizable: Bool,
+        resizable: Bool
+    ) {
+        window.closable = closable
+        window.minimizable = minimizable
         window.resizable = resizable
     }
 
@@ -284,8 +294,13 @@ public final class DummyBackend: AppBackend {
         window.size = newSize
     }
 
-    public func setMinimumSize(ofWindow window: Window, to minimumSize: SIMD2<Int>) {
+    public func setSizeLimits(
+        ofWindow window: Window,
+        minimum minimumSize: SIMD2<Int>,
+        maximum maximumSize: SIMD2<Int>?
+    ) {
         window.minimumSize = minimumSize
+        window.maximumSize = maximumSize
     }
 
     public func setResizeHandler(ofWindow window: Window, to action: @escaping (SIMD2<Int>) -> Void)

Sources/Gtk/Widgets/Window.swift

@@ -13,6 +13,7 @@ open class Window: Widget {
 
     @GObjectProperty(named: "title") public var title: String?
     @GObjectProperty(named: "resizable") public var resizable: Bool
+    @GObjectProperty(named: "deletable") public var deletable: Bool
     @GObjectProperty(named: "modal") public var isModal: Bool
     @GObjectProperty(named: "decorated") public var isDecorated: Bool
     @GObjectProperty(named: "destroy-with-parent") public var destroyWithParent: Bool

Sources/Gtk3/Widgets/Window.swift

@@ -11,6 +11,7 @@ open class Window: Bin {
 
     @GObjectProperty(named: "title") public var title: String?
     @GObjectProperty(named: "resizable") public var resizable: Bool
+    @GObjectProperty(named: "deletable") public var deletable: Bool
     @GObjectProperty(named: "modal") public var isModal: Bool
     @GObjectProperty(named: "decorated") public var isDecorated: Bool
 

Sources/Gtk3Backend/Gtk3Backend.swift

@@ -50,6 +50,28 @@ public final class Gtk3Backend: AppBackend {
     /// precreated window until it gets 'created' via `createWindow`.
     var windows: [Window] = []
 
+    private struct LogLocation: Hashable, Equatable {
+        let file: String
+        let line: Int
+        let column: Int
+    }
+
+    private var logsPerformed: Set<LogLocation> = []
+
+    func debugLogOnce(
+        _ message: String,
+        file: String = #file,
+        line: Int = #line,
+        column: Int = #column
+    ) {
+        #if DEBUG
+            let location = LogLocation(file: file, line: line, column: column)
+            if logsPerformed.insert(location).inserted {
+                logger.notice("\(message)")
+            }
+        #endif
+    }
+
     // A separate initializer to satisfy ``AppBackend``'s requirements.
     public convenience init() {
         self.init(appIdentifier: nil)
@@ -160,7 +182,18 @@ public final class Gtk3Backend: AppBackend {
         window.title = title
     }
 
-    public func setResizability(ofWindow window: Window, to resizable: Bool) {
+    public func setBehaviors(
+        ofWindow window: Window,
+        closable: Bool,
+        minimizable: Bool,
+        resizable: Bool
+    ) {
+        // FIXME: This doesn't seem to work on macOS at least
+        window.deletable = closable
+
+        // TODO: Figure out if there's some magic way to disable minimization
+        //   in a framework where the minimize button usually doesn't even exist
+
         window.resizable = resizable
     }
 
@@ -207,9 +240,19 @@ public final class Gtk3Backend: AppBackend {
         )
     }
 
-    public func setMinimumSize(ofWindow window: Window, to minimumSize: SIMD2<Int>) {
+    public func setSizeLimits(
+        ofWindow window: Window,
+        minimum minimumSize: SIMD2<Int>,
+        maximum maximumSize: SIMD2<Int>?
+    ) {
         let child = window.child! as! CustomRootWidget
         child.setMinimumSize(minimumWidth: minimumSize.x, minimumHeight: minimumSize.y)
+
+        // NB: GTK does not support setting maximum sizes for widgets. It just doesn't.
+        // https://discourse.gnome.org/t/how-to-build-fixed-size-windows-in-gtk-4/22807/10
+        if maximumSize != nil {
+            debugLogOnce("GTK does not support setting maximum window sizes")
+        }
     }
 
     public func setResizeHandler(

Sources/GtkBackend/GtkBackend.swift

@@ -55,6 +55,28 @@
     /// precreated window until it gets 'created' via `createWindow`.
     var windows: [Window] = []
 
+    private struct LogLocation: Hashable, Equatable {
+        let file: String
+        let line: Int
+        let column: Int
+    }
+
+    private var logsPerformed: Set<LogLocation> = []
+
+    func debugLogOnce(
+        _ message: String,
+        file: String = #file,
+        line: Int = #line,
+        column: Int = #column
+    ) {
+        #if DEBUG
+            let location = LogLocation(file: file, line: line, column: column)
+            if logsPerformed.insert(location).inserted {
+                logger.notice("\(message)")
+            }
+        #endif
+    }
+
     // A separate initializer to satisfy ``AppBackend``'s requirements.
     public convenience init() {
         self.init(appIdentifier: nil)
@@ -149,7 +171,18 @@
         window.title = title
     }
 
-    public func setResizability(ofWindow window: Window, to resizable: Bool) {
+    public func setBehaviors(
+        ofWindow window: Window,
+        closable: Bool,
+        minimizable: Bool,
+        resizable: Bool
+    ) {
+        // FIXME: This doesn't seem to work on macOS at least
+        window.deletable = closable
+
+        // TODO: Figure out if there's some magic way to disable minimization
+        //   in a framework where the minimize button usually doesn't even exist
+
         window.resizable = resizable
     }
 
@@ -164,7 +197,7 @@
         #else
             if window.showMenuBar {
                 // TODO: Don't hardcode this (if possible), because some Gtk
                 //   themes may affect the height of the menu bar.
                 25
             } else {
                 0
@@ -180,7 +213,7 @@
 
     public func isWindowProgrammaticallyResizable(_ window: Window) -> Bool {
         // TODO: Detect whether window is fullscreen
         return true
     }
 
     public func setSize(ofWindow window: Window, to newSize: SIMD2<Int>) {
@@ -192,8 +225,18 @@
         child.preemptAllocatedSize(allocatedWidth: newSize.x, allocatedHeight: newSize.y)
     }
 
-    public func setMinimumSize(ofWindow window: Window, to minimumSize: SIMD2<Int>) {
+    public func setSizeLimits(
+        ofWindow window: Window,
+        minimum minimumSize: SIMD2<Int>,
+        maximum maximumSize: SIMD2<Int>?
+    ) {
         window.setMinimumSize(to: Size(width: minimumSize.x, height: minimumSize.y))
+
+        // NB: GTK does not support setting maximum sizes for widgets. It just doesn't.
+        // https://discourse.gnome.org/t/how-to-build-fixed-size-windows-in-gtk-4/22807/10
+        if maximumSize != nil {
+            debugLogOnce("GTK does not support setting maximum window sizes")
+        }
     }
 
     public func setResizeHandler(
@@ -414,14 +457,14 @@
             }
         }
     }
 
     public func show(widget: Widget) {
         widget.show()
     }
 
     public func tag(widget: Widget, as tag: String) {
         widget.tag(as: tag)
     }
 
     // MARK: Containers
 
@@ -429,7 +472,7 @@
         return Fixed()
     }
 
     public func removeAllChildren(of container: Widget) {
         let container = container as! Fixed
         container.removeAllChildren()
     }
@@ -725,7 +768,7 @@
     //     }
 
     // }
 
     // public func setColumnCount(ofTable table: Widget, to columns: Int) {
     //     let table = table as! Grid
 
@@ -1218,7 +1261,7 @@
         chooser.response = { (_: NativeDialog, response: Int) -> Void in
             // Release our intentional retain cycle which ironically only exists
             // because of this line. The retain cycle keeps the file chooser
             // around long enough for the user to respond (it gets released
             // immediately if we don't do this in the response signal handler).
             chooser.response = nil
 
@@ -1251,7 +1294,7 @@
                 gtk_gesture_single_set_button(gtkGesture.opaquePointer, guint(GDK_BUTTON_SECONDARY))
             case .longPress:
                 gtkGesture = GestureLongPress()
         }
         child.addEventController(gtkGesture)
         return child
     }

Sources/SwiftCrossUI/Backend/AppBackend.swift

@@ -136,9 +136,20 @@ public protocol AppBackend: Sendable {
     func createWindow(withDefaultSize defaultSize: SIMD2<Int>?) -> Window
     /// Sets the title of a window.
     func setTitle(ofWindow window: Window, to title: String)
-    /// Sets the resizability of a window. Even if resizable, the window
-    /// shouldn't be allowed to become smaller than its content.
-    func setResizability(ofWindow window: Window, to resizable: Bool)
+    /// Sets the behaviors of a window.
+    /// - Parameters:
+    ///   - window: The window to set the behaviors on.
+    ///   - closable: Whether the window can be closed by the user.
+    ///   - minimizable: Whether the window can be minimized by the user.
+    ///   - resizable: Whether the window can be resized by the user. Even if
+    ///     resizable, the window shouldn't be allowed to become smaller than its
+    ///     minimum size, or larger than its maximum size.
+    func setBehaviors(
+        ofWindow window: Window,
+        closable: Bool,
+        minimizable: Bool,
+        resizable: Bool
+    )
     /// Sets the root child of a window (replaces the previous child if any).
     func setChild(ofWindow window: Window, to child: Widget)
     /// Gets the size of the given window in pixels.
@@ -148,9 +159,20 @@ public protocol AppBackend: Sendable {
     func isWindowProgrammaticallyResizable(_ window: Window) -> Bool
     /// Sets the size of the given window in pixels.
     func setSize(ofWindow window: Window, to newSize: SIMD2<Int>)
-    /// Sets the minimum width and height of the window. Prevents the user from making the
-    /// window any smaller than the given size.
-    func setMinimumSize(ofWindow window: Window, to minimumSize: SIMD2<Int>)
+    /// Sets the minimum and maximum width and height of a window.
+    ///
+    /// Prevents the user from making the window any smaller or larger than the given minimum and
+    /// maximum sizes, respectively.
+    /// - Parameters:
+    ///   - window: The window to set the size limits of.
+    ///   - minimumSize: The minimum window size.
+    ///   - maximumSize: The maximum window size. If `nil`, any existing maximum size
+    ///     constraints should be removed.
+    func setSizeLimits(
+        ofWindow window: Window,
+        minimum minimumSize: SIMD2<Int>,
+        maximum maximumSize: SIMD2<Int>?
+    )
     /// Sets the handler for the window's resizing events. `action` takes the proposed size
     /// of the window and returns the final size for the window (which allows SwiftCrossUI
     /// to implement features such as dynamic minimum window sizes based off the content's

Sources/SwiftCrossUI/Environment/EnvironmentValues.swift

@@ -98,6 +98,9 @@ public struct EnvironmentValues {
     /// Whether the text should be selectable. Set by ``View/textSelectionEnabled(_:)``.
     public var isTextSelectionEnabled: Bool
 
+    /// The resizing behaviour of the current window.
+    var windowResizability: WindowResizability
+
     /// The menu ordering to use.
     public var menuOrder: MenuOrder
 
@@ -229,6 +232,7 @@ public struct EnvironmentValues {
         isEnabled = true
         scrollDismissesKeyboardMode = .automatic
         isTextSelectionEnabled = false
+        windowResizability = .automatic
         menuOrder = .automatic
         allowLayoutCaching = false
     }

Sources/SwiftCrossUI/Scenes/Modifiers/WindowResizabilityModifier.swift

@@ -0,0 +1,12 @@
+extension Scene {
+    /// Sets the resizability of windows controlled by this scene.
+    ///
+    /// This modifier controls how SwiftCrossUI determines the bounds within which
+    /// windows can be resized, whereas ``View/windowResizeBehavior(_:)`` controls
+    /// whether the user can resize the enclosing window. The only time this
+    /// modifier can disable interactive resizing is when a window's content has
+    /// a fixed size and `resizability` is ``WindowResizability/contentSize``.
+    public func windowResizability(_ resizability: WindowResizability) -> some Scene {
+        environment(\.windowResizability, resizability)
+    }
+}