Update toggleStyle to be an environment modifier

This means that toggleStyle can now be applied to whole view
hierarchies at a time.

Author: stackotter

Sources/AppKitBackend/AppKitBackend.swift

@@ -20,7 +20,6 @@ public final class AppKitBackend: AppBackend {
     public let defaultTableCellVerticalPadding = 4
     public let defaultPaddingAmount = 10
     public let requiresToggleSwitchSpacer = false
-    public let defaultToggleStyle = ToggleStyle.button
     public let requiresImageUpdateOnScaleFactorChange = false
     public let menuImplementationStyle = MenuImplementationStyle.dynamicPopover
     public let canRevealFiles = true

Sources/Gtk3Backend/Gtk3Backend.swift

@@ -33,7 +33,6 @@ public final class Gtk3Backend: AppBackend {
     public let defaultPaddingAmount = 10
     public let requiresToggleSwitchSpacer = false
     public let scrollBarWidth = 0
-    public let defaultToggleStyle = ToggleStyle.button
     public let requiresImageUpdateOnScaleFactorChange = true
     public let menuImplementationStyle = MenuImplementationStyle.dynamicPopover
     public let canRevealFiles = true

Sources/GtkBackend/GtkBackend.swift

@@ -32,7 +32,6 @@ public final class GtkBackend: AppBackend {
     public let defaultPaddingAmount = 10
     public let scrollBarWidth = 0
     public let requiresToggleSwitchSpacer = false
-    public let defaultToggleStyle = ToggleStyle.button
     public let requiresImageUpdateOnScaleFactorChange = false
     public let menuImplementationStyle = MenuImplementationStyle.dynamicPopover
     public let canRevealFiles = true

Sources/SwiftCrossUI/Backend/AppBackend.swift

@@ -75,8 +75,6 @@ public protocol AppBackend {
     var scrollBarWidth: Int { get }
     /// If `true`, a toggle in the ``ToggleStyle/switch`` style grows to fill its parent container.
     var requiresToggleSwitchSpacer: Bool { get }
-    /// The default style for toggles.
-    var defaultToggleStyle: ToggleStyle { get }
     /// If `true`, all images in a window will get updated when the window's
     /// scale factor changes (``EnvironmentValues/windowScaleFactor``).
     ///

Sources/SwiftCrossUI/Environment/EnvironmentValues.swift

@@ -60,6 +60,9 @@ public struct EnvironmentValues {
     /// The style of list to use.
     package var listStyle: ListStyle
 
+    /// The style of toggle to use.
+    public var toggleStyle: ToggleStyle
+
     // Backing storage for extensible subscript
     private var extraValues: [ObjectIdentifier: Any]
 
@@ -163,6 +166,7 @@ public struct EnvironmentValues {
         window = nil
         extraValues = [:]
         listStyle = .default
+        toggleStyle = .button
         isEnabled = true
     }
 

Sources/SwiftCrossUI/Views/Modifiers/Style/ToggleStyleModifier.swift

@@ -0,0 +1,8 @@
+extension View {
+    /// Sets the style of the toggle.
+    public func toggleStyle(_ toggleStyle: ToggleStyle) -> some View {
+        return EnvironmentModifier(self) { environment in
+            return environment.with(\.toggleStyle, toggleStyle)
+        }
+    }
+}

Sources/SwiftCrossUI/Views/Toggle.swift

@@ -1,8 +1,8 @@
+/// A control for toggling between two values (usually representing on and off).
 public struct Toggle: View {
     @Environment(\.backend) var backend
+    @Environment(\.toggleStyle) var toggleStyle
 
-    /// The style of toggle shown.
-    var selectedToggleStyle: ToggleStyle?
     /// The label to be shown on or beside the toggle.
     var label: String
     /// Whether the toggle is active or not.
@@ -15,7 +15,7 @@ public struct Toggle: View {
     }
 
     public var body: some View {
-        switch selectedToggleStyle ?? backend.defaultToggleStyle {
+        switch toggleStyle.style {
             case .switch:
                 HStack {
                     Text(label)
@@ -32,16 +32,18 @@ public struct Toggle: View {
     }
 }
 
-extension Toggle {
-    /// Sets the style of the toggle.
-    public func toggleStyle(_ selectedToggleStyle: ToggleStyle) -> Toggle {
-        var toggle = self
-        toggle.selectedToggleStyle = selectedToggleStyle
-        return toggle
-    }
-}
+/// A style of toggle.
+public struct ToggleStyle {
+    package var style: Style
 
-public enum ToggleStyle {
-    case `switch`
-    case button
+    /// A toggle switch.
+    public static let `switch` = Self(style: .switch)
+    /// A toggle button. Generally looks like a regular button when off and an
+    /// accented button when on.
+    public static let button = Self(style: .button)
+
+    package enum Style {
+        case `switch`
+        case button
+    }
 }

Sources/UIKitBackend/UIKitBackend.swift

@@ -13,7 +13,6 @@ public final class UIKitBackend: AppBackend {
     public let scrollBarWidth = 0
     public let defaultPaddingAmount = 15
     public let requiresToggleSwitchSpacer = true
-    public let defaultToggleStyle = ToggleStyle.switch
     public let menuImplementationStyle = MenuImplementationStyle.menuButton
 
     // TODO: When tables are supported, update these
@@ -76,6 +75,8 @@ public final class UIKitBackend: AppBackend {
             design: .default
         )
 
+        environment.toggleStyle = .switch
+
         switch UITraitCollection.current.userInterfaceStyle {
             case .light:
                 environment.colorScheme = .light

Sources/WinUIBackend/WinUIBackend.swift

@@ -39,7 +39,6 @@ public final class WinUIBackend: AppBackend {
     public let defaultTableCellVerticalPadding = 4
     public let defaultPaddingAmount = 10
     public let requiresToggleSwitchSpacer = false
-    public let defaultToggleStyle = ToggleStyle.button
     public let requiresImageUpdateOnScaleFactorChange = false
     public let menuImplementationStyle = MenuImplementationStyle.dynamicPopover
     public let canRevealFiles = false