Merge branch 'main' into 1.0.0

.github/workflows/docs.yml

@@ -46,7 +46,7 @@ jobs:
       - name: Modify Docs
         run: |
           echo "<script>window.location.href += \"/documentation/adwaita\"</script>" > docs/index.html;
-          sed -i '' 's/#06f/#ea3358/g' docs/css/documentation-topic~topic~tutorials-overview.d6f5411c.css
+          sed -i '' 's/#06f/#ea3358/g' docs/css/documentation-topic~topic~tutorials-overview.*.css
           sed -i '' 's/,2px/,10px/g' docs/css/index.*.css
       - name: Upload Artifact
         uses: actions/upload-pages-artifact@v3

Sources/Adwaita/Model/Data Flow/Binding.swift

@@ -0,0 +1,150 @@
+//
+//  Binding.swift
+//  Adwaita
+//
+//  Created by david-swift on 06.08.23.
+//
+
+/// A property wrapper for a property of a view that binds the property of the parent view.
+///
+/// ```swift
+/// struct Grandparent: View {
+///
+///     @State private var state = false
+///
+///     var view: Body {
+///         Parent(value: $state)
+///     }
+/// }
+///
+/// struct Parent: View {
+///
+///     @Binding var value: Bool
+///
+///     var view: Body {
+///         Child(value: $value)
+///     }
+///
+/// }
+///
+/// struct Child: View {
+///
+///     @Binding var value: Bool
+///
+///     var view: Body {
+///         // ...
+///     }
+///
+/// }
+/// ```
+@propertyWrapper
+@dynamicMemberLookup
+public struct Binding<Value> {
+
+    /// The value.
+    public var wrappedValue: Value {
+        get {
+            getValue()
+        }
+        nonmutating set {
+            setValue(newValue)
+            for handler in handlers {
+                handler(newValue)
+            }
+        }
+    }
+
+    /// Get the value as a binding using the `$` prefix.
+    public var projectedValue: Binding<Value> {
+        .init {
+            wrappedValue
+        } set: { newValue in
+            wrappedValue = newValue
+        }
+    }
+
+    /// The closure for getting the value.
+    private let getValue: () -> Value
+    /// The closure for settings the value.
+    private let setValue: (Value) -> Void
+    /// Handlers observing whether the binding changes.
+    private var handlers: [(Value) -> Void] = []
+
+    /// Get a property of any content of a `Binding` as a `Binding`.
+    /// - Parameter dynamicMember: The path to the member.
+    /// - Returns: The binding.
+    public subscript<Subject>(dynamicMember keyPath: WritableKeyPath<Value, Subject>) -> Binding<Subject> {
+        .init {
+            wrappedValue[keyPath: keyPath]
+        } set: { newValue in
+            wrappedValue[keyPath: keyPath] = newValue
+        }
+    }
+
+    /// Initialize a property that is bound from a parent view.
+    /// - Parameters:
+    ///   - get: The closure for getting the value.
+    ///   - set: The closure for setting the value.
+    public init(get: @escaping () -> Value, set: @escaping (Value) -> Void) {
+        self.getValue = get
+        self.setValue = set
+    }
+
+    /// Initialize a property that does not react to changes in the child view.
+    /// - Parameters:
+    ///     - value: The constant value.
+    /// - Returns: The binding.
+    public static func constant(_ value: Value) -> Binding<Value> {
+        .init {
+            value
+        } set: { _ in
+        }
+    }
+
+    /// Observe whether data is changed over this binding.
+    /// - Parameter handler: The handler.
+    /// - Returns: The binding.
+    public func onSet(_ handler: @escaping (Value) -> Void) -> Self {
+        var newSelf = self
+        newSelf.handlers.append(handler)
+        return newSelf
+    }
+
+}
+
+/// An extension
+extension Binding where Value: MutableCollection {
+
+    /// Get a child at a certain index of the array as a binding.
+    /// - Parameters:
+    ///     - index: The child's index.
+    ///     - defaultValue: The value used if the index is out of range does not exist.
+    /// - Returns: The child as a binding.
+    public subscript(safe index: Value.Index?, default defaultValue: Value.Element) -> Binding<Value.Element> {
+        .init {
+            if let index, wrappedValue.indices.contains(index) {
+                return wrappedValue[index]
+            }
+            return defaultValue
+        } set: { newValue in
+            if let index, wrappedValue.indices.contains(index) {
+                wrappedValue[index] = newValue
+            }
+        }
+    }
+
+}
+
+/// An extension
+extension Binding where Value: MutableCollection, Value.Element: Identifiable {
+
+    /// Get a child of the array with a certain id as a binding.
+    /// - Parameters:
+    ///     - id: The child's id.
+    ///     - defaultValue: The value used if the index is out of range does not exist.
+    /// - Returns: The child as a binding.
+    public subscript(id id: Value.Element.ID?, default defaultValue: Value.Element) -> Binding<Value.Element> {
+        self[safe: wrappedValue.firstIndex { $0.id == id }, default: defaultValue]
+    }
+
+}