Create basic Table view

Author: stackotter

Examples/SpreadSheet/SpreadsheetApp.swift

@@ -0,0 +1,46 @@
+import GtkBackend
+import SwiftCrossUI
+
+struct Person {
+    var name: String
+    var age: Int
+    var phone: String
+    var email: String
+    var occupation: String
+}
+
+class SpreadSheetState: Observable {
+    @Observed
+    var data = [
+        Person(
+            name: "Alice", age: 99, phone: "(+61)1234123412",
+            email: "alice@example.com", occupation: "developer"
+        ),
+        Person(
+            name: "Bob", age: 99, phone: "(+61)1234123412",
+            email: "bob@example.com", occupation: "adversary"
+        ),
+    ]
+}
+
+@main
+struct SpreadSheetApp: App {
+    typealias Backend = GtkBackend
+
+    let identifier = "dev.stackotter.SpreadSheetApp"
+
+    let state = SpreadSheetState()
+
+    let windowProperties = WindowProperties(title: "SpreadSheetApp", resizable: true)
+
+    var body: some ViewContent {
+        Table(state.data) {
+            TableColumn("Name", value: \Person.name)
+            TableColumn("Age", value: \Person.age)
+            TableColumn("Phone", value: \Person.phone)
+            TableColumn("Email", value: \Person.email)
+            TableColumn("Occupation", value: \Person.occupation)
+        }
+        .padding(10)
+    }
+}

Package.swift

@@ -224,6 +224,11 @@ let package = Package(
             dependencies: exampleDependencies,
             path: "Examples/Split"
         ),
+        .executableTarget(
+            name: "SpreadsheetExample",
+            dependencies: exampleDependencies,
+            path: "Examples/Spreadsheet"
+        ),
 
         .testTarget(
             name: "SwiftCrossUITests",

Sources/Gtk/Widgets/Grid.swift

@@ -15,7 +15,7 @@ import CGtk
 public class Grid: Widget, Orientable {
     var widgets: [Widget] = []
 
-    override init() {
+    public override init() {
         super.init()
 
         widgetPointer = gtk_grid_new()

Sources/GtkBackend/GtkBackend.swift

@@ -451,4 +451,74 @@ public struct GtkBackend: AppBackend {
     ) {
         (container as! ModifierBox).css.set(properties: [.foregroundColor(color.gtkColor)])
     }
+
+    private class Tables {
+        var tableSizes: [ObjectIdentifier: (rows: Int, columns: Int)] = [:]
+    }
+
+    private let tables = Tables()
+
+    public func createTable(rows: Int, columns: Int) -> Widget {
+        let widget = Grid()
+
+        for i in 0..<rows {
+            widget.insertRow(position: i)
+        }
+
+        for i in 0..<columns {
+            widget.insertRow(position: i)
+        }
+
+        tables.tableSizes[ObjectIdentifier(widget)] = (rows: rows, columns: columns)
+
+        widget.columnSpacing = 10
+        widget.rowSpacing = 10
+
+        return widget
+    }
+
+    public func setRowCount(ofTable table: Widget, to rows: Int) {
+        let table = table as! Grid
+
+        let rowDifference = rows - tables.tableSizes[ObjectIdentifier(table)]!.rows
+        tables.tableSizes[ObjectIdentifier(table)]!.rows = rows
+        if rowDifference < 0 {
+            for _ in 0..<(-rowDifference) {
+                table.removeRow(position: 0)
+            }
+        } else if rowDifference > 0 {
+            for _ in 0..<rowDifference {
+                table.insertRow(position: 0)
+            }
+        }
+
+    }
+
+    public func setColumnCount(ofTable table: Widget, to columns: Int) {
+        let table = table as! Grid
+
+        let columnDifference = columns - tables.tableSizes[ObjectIdentifier(table)]!.columns
+        tables.tableSizes[ObjectIdentifier(table)]!.columns = columns
+        if columnDifference < 0 {
+            for _ in 0..<(-columnDifference) {
+                table.removeColumn(position: 0)
+            }
+        } else if columnDifference > 0 {
+            for _ in 0..<columnDifference {
+                table.insertColumn(position: 0)
+            }
+        }
+
+    }
+
+    public func setCell(at position: CellPosition, inTable table: Widget, to widget: Widget) {
+        let table = table as! Grid
+        table.attach(
+            child: widget,
+            left: position.column,
+            top: position.row,
+            width: 1,
+            height: 1
+        )
+    }
 }

Sources/SwiftCrossUI/Backend/AppBackend.swift

@@ -111,13 +111,32 @@ public protocol AppBackend {
 
     func createForegroundColorContainer(for child: Widget, color: Color) -> Widget
     func setForegroundColor(ofForegroundColorContainer container: Widget, to color: Color)
+
+    func createTable(rows: Int, columns: Int) -> Widget
+    func setRowCount(ofTable table: Widget, to rows: Int)
+    func setColumnCount(ofTable table: Widget, to columns: Int)
+    func setCell(at position: CellPosition, inTable table: Widget, to widget: Widget)
 }
 
 public enum InheritedOrientation {
     case vertical
     case horizontal
 }
 
+/// The position of a cell in a table (with row and column numbers starting from 0).
+public struct CellPosition {
+    /// The row number starting from 0.
+    public var row: Int
+    /// The column number starting from 0.
+    public var column: Int
+
+    /// Creates a cell position from a row and column number (starting from 0).
+    public init(_ row: Int, _ column: Int) {
+        self.row = row
+        self.column = column
+    }
+}
+
 extension AppBackend {
     public func addChildren(_ children: [Widget], toVStack container: Widget) {
         for child in children {
@@ -156,12 +175,12 @@ extension AppBackend {
     }
 }
 
-private func todo(_ message: String) -> Never {
-    print(message)
-    Foundation.exit(1)
-}
-
 extension AppBackend {
+    private func todo(_ message: String) -> Never {
+        print("\(type(of: self)): message")
+        Foundation.exit(1)
+    }
+
     public func show(_ widget: Widget) {
         todo("show not implemented")
     }
@@ -373,4 +392,17 @@ extension AppBackend {
     public func setForegroundColor(ofForegroundColorContainer container: Widget, to color: Color) {
         todo("setForegroundColor not implemented")
     }
+
+    public func createTable(rows: Int, columns: Int) -> Widget {
+        todo("createTable not implemented")
+    }
+    public func setRowCount(ofTable table: Widget, to rows: Int) {
+        todo("setRowCount not implemented")
+    }
+    public func setColumnCount(ofTable table: Widget, to columns: Int) {
+        todo("setColumnCount not implemented")
+    }
+    public func setCell(at position: CellPosition, inTable table: Widget, to widget: Widget) {
+        todo("setCell not implemented")
+    }
 }

Sources/SwiftCrossUI/Builders/TableBuilder.swift

@@ -0,0 +1,30 @@
+@resultBuilder
+public struct TableBuilder<Row> {
+    public static func buildBlock() -> [TableColumn<Row>] {
+        []
+    }
+
+    public static func buildBlock(_ components: TableColumn<Row>...) -> [TableColumn<Row>] {
+        components
+    }
+
+    public static func buildArray(_ components: [TableColumn<Row>]) -> [TableColumn<Row>] {
+        components
+    }
+
+    public static func buildOptional(_ component: TableColumn<Row>?) -> [TableColumn<Row>] {
+        if let component = component {
+            [component]
+        } else {
+            []
+        }
+    }
+
+    public static func buildEither(first component: TableColumn<Row>) -> [TableColumn<Row>] {
+        [component]
+    }
+
+    public static func buildEither(second component: TableColumn<Row>) -> [TableColumn<Row>] {
+        [component]
+    }
+}

Sources/SwiftCrossUI/Views/Table.swift

@@ -0,0 +1,42 @@
+/// A table view.
+public struct Table<Row>: View {
+    public var body = EmptyViewContent()
+
+    private var rows: [Row]
+    private var columns: [TableColumn<Row>]
+
+    /// Creates a new text view with the given content.
+    public init(_ rows: [Row], @TableBuilder<Row> _ columns: () -> [TableColumn<Row>]) {
+        self.rows = rows
+        self.columns = columns()
+    }
+
+    public func asWidget<Backend: AppBackend>(
+        _ children: EmptyViewContent.Children,
+        backend: Backend
+    ) -> Backend.Widget {
+        return backend.createTable(rows: rows.count, columns: columns.count)
+    }
+
+    public func update<Backend: AppBackend>(
+        _ widget: Backend.Widget,
+        children: EmptyViewContent.Children,
+        backend: Backend
+    ) {
+        backend.setRowCount(ofTable: widget, to: rows.count)
+        backend.setColumnCount(ofTable: widget, to: columns.count)
+        for i in 0..<rows.count {
+            let row = rows[i]
+            for j in 0..<columns.count {
+                backend.setCell(
+                    at: CellPosition(i, j),
+                    inTable: widget,
+                    to: backend.createTextView(
+                        content: columns[j].value(row),
+                        shouldWrap: false
+                    )
+                )
+            }
+        }
+    }
+}

Sources/SwiftCrossUI/Views/TableColumn.swift

@@ -0,0 +1,21 @@
+public struct TableColumn<Row> {
+    public var title: String
+    public var value: (Row) -> String
+
+    public init(_ title: String, value keyPath: KeyPath<Row, String>) {
+        self.title = title
+        self.value = { row in
+            row[keyPath: keyPath]
+        }
+    }
+
+    public init<Value: CustomStringConvertible>(
+        _ title: String,
+        value keyPath: KeyPath<Row, Value>
+    ) {
+        self.title = title
+        self.value = { row in
+            row[keyPath: keyPath].description
+        }
+    }
+}