swiftui-dateformat-fix.swift

test-app.swift

// Run any SwiftUI view as a Mac app.

import Cocoa
import SwiftUI
import Foundation

public extension Date
{
    static let shortDateFormatter: DateFormatter = {
        let dateFormatter = DateFormatter()
        dateFormatter.dateStyle = .short
        dateFormatter.timeStyle = .none
        return dateFormatter
    }()

    static let mediumDateFormatter: DateFormatter = {
        let dateFormatter = DateFormatter()
        dateFormatter.dateStyle = .medium
        dateFormatter.timeStyle = .none
        return dateFormatter
    }()

    func numberOfCalendarDays(since date: Date) -> Int
    {
        let today = Calendar.current.startOfDay(for: self)
        let previousDay = Calendar.current.startOfDay(for: date)

        let components = Calendar.current.dateComponents([.day], from: previousDay, to: today)
        return components.day!
    }

    func relativeDateString(since date: Date, dateFormatter: DateFormatter? = nil) -> String
    {
        let dateFormatter = dateFormatter ?? Date.mediumDateFormatter
        let numberOfDays = self.numberOfCalendarDays(since: date)

        switch numberOfDays
        {
        case 0: return NSLocalizedString("Today", comment: "")
        case 1: return NSLocalizedString("Yesterday", comment: "")
        default: return dateFormatter.string(from: date)
        }
    }
}

let twoDaysAgo = Date.now.addingTimeInterval(-1 * 2 * 24 * 60 * 60)
let currentDate = Date()
let numberOfDays = max(twoDaysAgo.numberOfCalendarDays(since: currentDate), 0)
let numberOfDaysText: String

if numberOfDays == 1
{
    numberOfDaysText = NSLocalizedString("1 day", comment: "")
}
else
{
    numberOfDaysText = String(format: NSLocalizedString("%@ days", comment: ""), NSNumber(value: numberOfDays))
}

NSApplication.shared.run {
    VStack {
        Text(numberOfDaysText)
        	.padding()
            .background(Capsule().fill(Color.blue))
            .padding()
    }
    .frame(maxWidth: .infinity, maxHeight: .infinity)

}

extension NSApplication {
    public func run<V: View>(@ViewBuilder view: () -> V) {
        let appDelegate = AppDelegate(view())
        NSApp.setActivationPolicy(.regular)
        mainMenu = customMenu
        delegate = appDelegate
        run()
    }
}

// Inspired by https://www.cocoawithlove.com/2010/09/minimalist-cocoa-programming.html

extension NSApplication {
    var customMenu: NSMenu {
        let appMenu = NSMenuItem()
        appMenu.submenu = NSMenu()
        let appName = ProcessInfo.processInfo.processName
        appMenu.submenu?.addItem(NSMenuItem(title: "About \(appName)", action: #selector(NSApplication.orderFrontStandardAboutPanel(_:)), keyEquivalent: ""))
        appMenu.submenu?.addItem(NSMenuItem.separator())
        let services = NSMenuItem(title: "Services", action: nil, keyEquivalent: "")
        self.servicesMenu = NSMenu()
        services.submenu = self.servicesMenu
        appMenu.submenu?.addItem(services)
        appMenu.submenu?.addItem(NSMenuItem.separator())
        appMenu.submenu?.addItem(NSMenuItem(title: "Hide \(appName)", action: #selector(NSApplication.hide(_:)), keyEquivalent: "h"))
        let hideOthers = NSMenuItem(title: "Hide Others", action: #selector(NSApplication.hideOtherApplications(_:)), keyEquivalent: "h")
        hideOthers.keyEquivalentModifierMask = [.command, .option]
        appMenu.submenu?.addItem(hideOthers)
        appMenu.submenu?.addItem(NSMenuItem(title: "Show All", action: #selector(NSApplication.unhideAllApplications(_:)), keyEquivalent: ""))
        appMenu.submenu?.addItem(NSMenuItem.separator())
        appMenu.submenu?.addItem(NSMenuItem(title: "Quit \(appName)", action: #selector(NSApplication.terminate(_:)), keyEquivalent: "q"))

        let windowMenu = NSMenuItem()
        windowMenu.submenu = NSMenu(title: "Window")
        windowMenu.submenu?.addItem(NSMenuItem(title: "Minmize", action: #selector(NSWindow.miniaturize(_:)), keyEquivalent: "m"))
        windowMenu.submenu?.addItem(NSMenuItem(title: "Zoom", action: #selector(NSWindow.performZoom(_:)), keyEquivalent: ""))
        windowMenu.submenu?.addItem(NSMenuItem.separator())
        windowMenu.submenu?.addItem(NSMenuItem(title: "Show All", action: #selector(NSApplication.arrangeInFront(_:)), keyEquivalent: "m"))

        let mainMenu = NSMenu(title: "Main Menu")
        mainMenu.addItem(appMenu)
        mainMenu.addItem(windowMenu)
        return mainMenu
    }
}

class AppDelegate<V: View>: NSObject, NSApplicationDelegate, NSWindowDelegate {
    init(_ contentView: V) {
        self.contentView = contentView

    }
    var window: NSWindow!
    var hostingView: NSView?
    var contentView: V

    func applicationDidFinishLaunching(_ notification: Notification) {
        window = NSWindow(
            contentRect: NSRect(x: 0, y: 0, width: 480, height: 300),
            styleMask: [.titled, .closable, .miniaturizable, .resizable, .fullSizeContentView],
            backing: .buffered, defer: false)
        window.center()
        window.setFrameAutosaveName("Main Window")
        hostingView = NSHostingView(rootView: contentView)
        window.contentView = hostingView
        window.makeKeyAndOrderFront(nil)
        window.delegate = self
        NSApp.activate(ignoringOtherApps: true)
    }
}