Merge pull request #62 from PureSwift/feature/label

Author: colemancda

AndroidSwiftUICore/Sources/AndroidSwiftUICore/Primitives/Label.swift

@@ -0,0 +1,67 @@
+//
+//  Label.swift
+//  AndroidSwiftUICore
+//
+//  A title paired with an icon. Emitted as its own node (icon child, then title
+//  child) rather than desugared to an HStack, so `labelStyle` can drop either
+//  half — which it does through the same inherited-CompositionLocal mechanism the
+//  control styles use.
+//
+
+public struct Label<Title: View, Icon: View>: View {
+
+    internal let title: Title
+    internal let icon: Icon
+
+    public init(@ViewBuilder title: () -> Title, @ViewBuilder icon: () -> Icon) {
+        self.title = title()
+        self.icon = icon()
+    }
+
+    public typealias Body = Never
+}
+
+public extension Label where Title == Text, Icon == Image {
+    init<S: StringProtocol>(_ title: S, systemImage name: String) {
+        self.init(title: { Text(title) }, icon: { Image(systemName: name) })
+    }
+
+    init<S: StringProtocol>(_ title: S, image name: String) {
+        self.init(title: { Text(title) }, icon: { Image(name) })
+    }
+}
+
+extension Label: PrimitiveView {
+    public func _render(in context: ResolveContext) -> RenderNode {
+        // icon first, title second — the interpreter relies on that order to
+        // show or hide each half per the label style
+        let iconNode = Evaluator.resolve(icon, context.descending("icon"))
+        let titleNode = Evaluator.resolve(title, context.descending("title"))
+        return RenderNode(type: "Label", id: context.path, children: [iconNode, titleNode])
+    }
+}
+
+// MARK: - Style
+
+/// The built-in label styles. Like the control styles, this is the spelling
+/// only — the `LabelStyle` protocol for custom layouts isn't modeled.
+public struct _LabelStyle: Sendable {
+    internal let kind: String
+    public static let automatic = _LabelStyle(kind: "automatic")
+    public static let titleAndIcon = _LabelStyle(kind: "titleAndIcon")
+    public static let titleOnly = _LabelStyle(kind: "titleOnly")
+    public static let iconOnly = _LabelStyle(kind: "iconOnly")
+}
+
+public struct _LabelStyleModifier: RenderModifier {
+    let style: _LabelStyle
+    public var _modifierNode: ModifierNode {
+        ModifierNode(kind: "labelStyle", args: ["style": .string(style.kind)])
+    }
+}
+
+public extension View {
+    func labelStyle(_ style: _LabelStyle) -> ModifiedContent<Self, _LabelStyleModifier> {
+        modifier(_LabelStyleModifier(style: style))
+    }
+}

AndroidSwiftUICore/Tests/AndroidSwiftUICoreTests/EvaluatorTests.swift

@@ -305,6 +305,43 @@ struct ModifierTests {
         #expect(node.children.first?.type == "HStack")
     }
 
+    @Test("Label emits its icon then its title")
+    func label() {
+        let node = ViewHost(Label("Favorites", systemImage: "star.fill")).evaluate()
+        #expect(node.type == "Label")
+        #expect(node.children.count == 2)
+        // order matters: the interpreter shows/hides each half by position
+        #expect(node.children[0].type == "Image")
+        #expect(node.children[0].props["systemName"] == .string("star.fill"))
+        #expect(firstTextString(node.children[1]) == "Favorites")
+    }
+
+    @Test("Label takes an arbitrary title and icon")
+    func labelCustom() {
+        let node = ViewHost(
+            Label(title: { Text("Hi") }, icon: { Text("!") })
+        ).evaluate()
+        #expect(firstTextString(node.children[0]) == "!")     // icon slot
+        #expect(firstTextString(node.children[1]) == "Hi")    // title slot
+    }
+
+    @Test("labelStyle rides on the view, so it can be inherited")
+    func labelStyle() {
+        let node = ViewHost(
+            VStack {
+                Label("A", systemImage: "star")
+                Label("B", systemImage: "star")
+            }
+            .labelStyle(.iconOnly)
+        ).evaluate()
+        #expect(node.modifiers.first { $0.kind == "labelStyle" }?.args["style"] == .string("iconOnly"))
+        // the container carries it; the labels themselves carry none
+        for child in node.children {
+            #expect(child.type == "Label")
+            #expect(child.modifiers.first { $0.kind == "labelStyle" } == nil)
+        }
+    }
+
     @Test("onAppear and onDisappear emit distinct callback kinds")
     func appearDisappear() {
         let node = ViewHost(Text("x").onAppear {}.onDisappear {}).evaluate()

Demo/App.swiftpm/Sources/Catalog.swift

@@ -40,6 +40,7 @@ struct CatalogEntry: Identifiable {
         CatalogEntry(id: "frame", title: "Frames", screen: AnyCatalogScreen(FramePlayground())),
         CatalogEntry(id: "spacer", title: "Spacer & Divider", screen: AnyCatalogScreen(SpacerDividerPlayground())),
         CatalogEntry(id: "color", title: "Color", screen: AnyCatalogScreen(ColorPlayground())),
+        CatalogEntry(id: "label", title: "Label", screen: AnyCatalogScreen(LabelPlayground())),
         CatalogEntry(id: "image", title: "Images", screen: AnyCatalogScreen(ImagePlayground())),
         CatalogEntry(id: "graphics", title: "Graphics", screen: AnyCatalogScreen(GraphicsPlayground())),
         CatalogEntry(id: "link", title: "Link", screen: AnyCatalogScreen(LinkPlayground())),

Demo/App.swiftpm/Sources/LabelPlaygrounds.swift

@@ -0,0 +1,38 @@
+#if canImport(AndroidSwiftUI)
+import AndroidSwiftUI
+#else
+import SwiftUI
+#endif
+
+struct LabelPlayground: View {
+    var body: some View {
+        ScrollView {
+            VStack(alignment: .leading, spacing: 0) {
+                Example("Label") {
+                    VStack(alignment: .leading, spacing: 10) {
+                        Label("Favorites", systemImage: "star.fill")
+                        Label("Delete", systemImage: "trash")
+                        Label("Mail", systemImage: "envelope")
+                    }
+                }
+                Example("labelStyle(.titleOnly)") {
+                    Label("Only the title", systemImage: "star.fill")
+                        .labelStyle(.titleOnly)
+                }
+                Example("labelStyle(.iconOnly)") {
+                    Label("Hidden title", systemImage: "star.fill")
+                        .labelStyle(.iconOnly)
+                }
+                Example("Inherited by a container") {
+                    // one style styles both labels
+                    VStack(alignment: .leading, spacing: 10) {
+                        Label("Inherited one", systemImage: "heart.fill")
+                        Label("Inherited two", systemImage: "heart.fill")
+                    }
+                    .labelStyle(.iconOnly)
+                }
+            }
+        }
+        .navigationTitle("Label")
+    }
+}

Demo/swiftui/src/commonMain/kotlin/com/pureswift/swiftui/Render.kt

@@ -207,6 +207,7 @@ internal val LocalButtonStyle = compositionLocalOf { "automatic" }
 internal val LocalPickerStyle = compositionLocalOf { "automatic" }
 internal val LocalToggleStyle = compositionLocalOf { "automatic" }
 internal val LocalTextFieldStyle = compositionLocalOf { "automatic" }
+internal val LocalLabelStyle = compositionLocalOf { "automatic" }
 
 /// Interprets a Swift-evaluated node tree into Material 3 composables.
 ///
@@ -242,6 +243,7 @@ internal fun RenderChild(node: ViewNode) {
     var pickerStyle = LocalPickerStyle.current
     var toggleStyle = LocalToggleStyle.current
     var textFieldStyle = LocalTextFieldStyle.current
+    var labelStyle = LocalLabelStyle.current
     for (m in node.modifiers) {
         when (m.kind) {
             "font" -> {
@@ -260,6 +262,7 @@ internal fun RenderChild(node: ViewNode) {
             "pickerStyle" -> m.args.string("style")?.let { pickerStyle = it }
             "toggleStyle" -> m.args.string("style")?.let { toggleStyle = it }
             "textFieldStyle" -> m.args.string("style")?.let { textFieldStyle = it }
+            "labelStyle" -> m.args.string("style")?.let { labelStyle = it }
         }
     }
 
@@ -274,6 +277,7 @@ internal fun RenderChild(node: ViewNode) {
         LocalPickerStyle provides pickerStyle,
         LocalToggleStyle provides toggleStyle,
         LocalTextFieldStyle provides textFieldStyle,
+        LocalLabelStyle provides labelStyle,
     ) { RenderResolved(node) }
 }
 
@@ -343,6 +347,8 @@ private fun RenderResolved(node: ViewNode) {
                 }
             }
 
+            "Label" -> RenderLabel(node)
+
             "Link" -> RenderLink(node)
 
             "GeometryReader" -> RenderGeometryReader(node)
@@ -601,6 +607,24 @@ private fun RenderLink(node: ViewNode) {
     }
 }
 
+// children are [icon, title]; the inherited label style may drop either half.
+@Composable
+private fun RenderLabel(node: ViewNode) {
+    val icon = node.children.getOrNull(0)
+    val title = node.children.getOrNull(1)
+    val style = LocalLabelStyle.current
+    val showIcon = style != "titleOnly"
+    val showTitle = style != "iconOnly"
+    Row(
+        verticalAlignment = Alignment.CenterVertically,
+        horizontalArrangement = Arrangement.spacedBy(6.dp),
+        modifier = node.composeModifiers(),
+    ) {
+        if (showIcon) icon?.let { RenderChild(it) }
+        if (showTitle) title?.let { RenderChild(it) }
+    }
+}
+
 private fun ViewNode.isPresentation(): Boolean =
     type == "Sheet" || type == "Alert" || type == "ConfirmationDialog" || type == "ToolbarItem"
 
@@ -1548,7 +1572,7 @@ private val KNOWN_MODIFIER_KINDS = setOf(
     "transition", "focused", "longPress", "drag", "contentMode", "progressViewStyle",
     "buttonStyle", "pickerStyle", "toggleStyle", "textFieldStyle",
     "accessibilityLabel", "accessibilityValue", "accessibilityHidden",
-    "accessibilityAddTraits", "accessibilityIdentifier",
+    "accessibilityAddTraits", "accessibilityIdentifier", "labelStyle",
 )
 
 // Folds a frame entry: fixed size, fill (maxWidth/Height .infinity), bounded