macos-native

What this skill does

# macOS Native Development

Comprehensive guide for building native macOS applications with AppKit and modern macOS APIs.

## Framework Overview

| Framework            | Use Case             | Notes                       |
| -------------------- | -------------------- | --------------------------- |
| **AppKit**           | Traditional Mac apps | Full control, mature        |
| **SwiftUI**          | Modern Mac apps      | Cross-platform, declarative |
| **Catalyst**         | iPad apps on Mac     | Quick port, limitations     |
| **AppKit + SwiftUI** | Hybrid approach      | Best of both worlds         |

---

## AppKit Fundamentals

### Application Structure

```swift
// AppDelegate.swift
import Cocoa

@main
class AppDelegate: NSObject, NSApplicationDelegate {
    var mainWindow: NSWindow?

    func applicationDidFinishLaunching(_ notification: Notification) {
        setupMainWindow()
        setupMainMenu()
    }

    func applicationWillTerminate(_ notification: Notification) {
        // Cleanup
    }

    func applicationShouldTerminateAfterLastWindowClosed(_ sender: NSApplication) -> Bool {
        return true
    }

    private func setupMainWindow() {
        let contentRect = NSRect(x: 0, y: 0, width: 800, height: 600)
        let styleMask: NSWindow.StyleMask = [
            .titled, .closable, .miniaturizable, .resizable
        ]

        mainWindow = NSWindow(
            contentRect: contentRect,
            styleMask: styleMask,
            backing: .buffered,
            defer: false
        )

        mainWindow?.title = "My Mac App"
        mainWindow?.contentViewController = MainViewController()
        mainWindow?.center()
        mainWindow?.makeKeyAndOrderFront(nil)
    }
}
```

### View Controller

```swift
import Cocoa

class MainViewController: NSViewController {
    private let tableView = NSTableView()
    private let scrollView = NSScrollView()
    private var items: [String] = []

    override func loadView() {
        view = NSView(frame: NSRect(x: 0, y: 0, width: 800, height: 600))
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        setupUI()
        loadData()
    }

    private func setupUI() {
        // Setup scroll view
        scrollView.translatesAutoresizingMaskIntoConstraints = false
        scrollView.hasVerticalScroller = true
        scrollView.documentView = tableView
        view.addSubview(scrollView)

        // Setup table view
        let column = NSTableColumn(identifier: NSUserInterfaceItemIdentifier("main"))
        column.title = "Items"
        column.width = 200
        tableView.addTableColumn(column)
        tableView.delegate = self
        tableView.dataSource = self

        // Constraints
        NSLayoutConstraint.activate([
            scrollView.topAnchor.constraint(equalTo: view.topAnchor, constant: 20),
            scrollView.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 20),
            scrollView.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -20),
            scrollView.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -20),
        ])
    }

    private func loadData() {
        items = ["Item 1", "Item 2", "Item 3"]
        tableView.reloadData()
    }
}

extension MainViewController: NSTableViewDataSource, NSTableViewDelegate {
    func numberOfRows(in tableView: NSTableView) -> Int {
        return items.count
    }

    func tableView(_ tableView: NSTableView, viewFor tableColumn: NSTableColumn?, row: Int) -> NSView? {
        let identifier = NSUserInterfaceItemIdentifier("cell")
        var cell = tableView.makeView(withIdentifier: identifier, owner: nil) as? NSTextField

        if cell == nil {
            cell = NSTextField(labelWithString: "")
            cell?.identifier = identifier
        }

        cell?.stringValue = items[row]
        return cell
    }
}
```

---

## Menu Bar Apps

### Status Item

```swift
import Cocoa

class StatusBarController {
    private var statusItem: NSStatusItem?
    private var popover: NSPopover?

    init() {
        setupStatusItem()
        setupPopover()
    }

    private func setupStatusItem() {
        statusItem = NSStatusBar.system.statusItem(withLength: NSStatusItem.variableLength)

        if let button = statusItem?.button {
            button.image = NSImage(systemSymbolName: "star.fill", accessibilityDescription: "App")
            button.action = #selector(togglePopover)
            button.target = self
        }
    }

    private func setupPopover() {
        popover = NSPopover()
        popover?.contentViewController = PopoverViewController()
        popover?.behavior = .transient
    }

    @objc private func togglePopover() {
        guard let button = statusItem?.button, let popover = popover else { return }

        if popover.isShown {
            popover.performClose(nil)
        } else {
            popover.show(relativeTo: button.bounds, of: button, preferredEdge: .minY)
            NSApp.activate(ignoringOtherApps: true)
        }
    }
}

class PopoverViewController: NSViewController {
    override func loadView() {
        view = NSView(frame: NSRect(x: 0, y: 0, width: 300, height: 200))
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        let label = NSTextField(labelWithString: "Menu Bar App Content")
        label.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(label)

        NSLayoutConstraint.activate([
            label.centerXAnchor.constraint(equalTo: view.centerXAnchor),
            label.centerYAnchor.constraint(equalTo: view.centerYAnchor),
        ])
    }
}
```

### Menu Construction

```swift
func setupMainMenu() {
    let mainMenu = NSMenu()

    // App Menu
    let appMenu = NSMenu()
    let appMenuItem = NSMenuItem()
    appMenuItem.submenu = appMenu

    appMenu.addItem(withTitle: "About My App", action: #selector(NSApplication.orderFrontStandardAboutPanel(_:)), keyEquivalent: "")
    appMenu.addItem(NSMenuItem.separator())
    appMenu.addItem(withTitle: "Preferences...", action: #selector(showPreferences), keyEquivalent: ",")
    appMenu.addItem(NSMenuItem.separator())
    appMenu.addItem(withTitle: "Quit My App", action: #selector(NSApplication.terminate(_:)), keyEquivalent: "q")

    mainMenu.addItem(appMenuItem)

    // File Menu
    let fileMenu = NSMenu(title: "File")
    let fileMenuItem = NSMenuItem()
    fileMenuItem.submenu = fileMenu

    fileMenu.addItem(withTitle: "New", action: #selector(newDocument), keyEquivalent: "n")
    fileMenu.addItem(withTitle: "Open...", action: #selector(openDocument), keyEquivalent: "o")
    fileMenu.addItem(NSMenuItem.separator())
    fileMenu.addItem(withTitle: "Save", action: #selector(saveDocument), keyEquivalent: "s")

    mainMenu.addItem(fileMenuItem)

    // Edit Menu
    let editMenu = NSMenu(title: "Edit")
    let editMenuItem = NSMenuItem()
    editMenuItem.submenu = editMenu

    editMenu.addItem(withTitle: "Undo", action: Selector(("undo:")), keyEquivalent: "z")
    editMenu.addItem(withTitle: "Redo", action: Selector(("redo:")), keyEquivalent: "Z")
    editMenu.addItem(NSMenuItem.separator())
    editMenu.addItem(withTitle: "Cut", action: #selector(NSText.cut(_:)), keyEquivalent: "x")
    editMenu.addItem(withTitle: "Copy", action: #selector(NSText.copy(_:)), keyEquivalent: "c")
    editMenu.addItem(withTitle: "Paste", action: #selector(NSText.paste(_:)), keyEquivalent: "v")

    mainMenu.addItem(editMenuItem)

    NSApp.mainMenu = mainMenu
}
```

---

## Document-Based Apps

### Document Controller

```swift
import Cocoa
import UniformTypeIdentifiers

class MyDocument: NSDocument {
    var content: String = ""

    override class var autosavesInPlace: Bool { true }

    override func makeWindowControllers() {
        let storyboard = NSStoryboard(name: "Main", bundle: nil)
        let windowController = storyboard.instantiateController(
            withIdentifier: "Document Window Controller"
        ) a