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Marcin Krzyzanowski krzyzanowskim

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krzyzanowskim / PastelColor.swift
Last active Jul 28, 2022
Random pastel colors
View PastelColor.swift
struct ContentView: View {
@State var color: Color = .Pastel.random()
var body: some View {
.onTapGesture {
color = .Pastel.random()
View AppSettings.swift
// Usage
final class AppSettings: ObservableObject {
static let standard = AppSettings()
@Published(preferenceKey: AppSettingsKey.editorHighlightSelectedLine)
var editorHighlightSelectedLine: Bool = true
View STPopUpMenu.swift
import AppKit
import SwiftUI
.popUpMenu {
NSMenuItem(title: "One", action: nil, keyEquivalent: "")
NSMenuItem(title: "Two", action: nil, keyEquivalent: "")
View VisualEffectView.swift
struct VisualEffectView: NSViewRepresentable {
let material: NSVisualEffectView.Material
let blendingMode: NSVisualEffectView.BlendingMode
init(material: NSVisualEffectView.Material, blendingMode: NSVisualEffectView.BlendingMode = .withinWindow) {
self.material = material
self.blendingMode = blendingMode
func makeNSView(context: Context) -> NSVisualEffectView {
View OptionSetIterator.swift
public struct OptionSetIterator<Element: OptionSet>: IteratorProtocol where Element.RawValue == Int {
private let value: Element
init(element: Element) {
self.value = element
private lazy var remainingBits = value.rawValue
private var bitMask = 1
View AsyncWaiter.swift
/// Wait for async operation to return value and call callback with the value
/// This class is intended to workaround/simplify async/await + actors isolation
private class AsyncWaiter<T> {
var didReceiveValue: Bool = false
let value: (T) -> Void
let operation: () async throws -> T
init(_ value: @escaping (T) -> Void, operation: @escaping () async throws -> T) {
self.value = value
View String.stride.swift
extension String {
func stride(by distance: String.IndexDistance, substring: (String.SubSequence) -> Void) {
guard distance > 0, distance < count else {
var i = index(startIndex, offsetBy: distance, limitedBy: endIndex) ?? endIndex
var previ = startIndex
while i < endIndex {
View SharingServicePicker.swift
struct SharingServicePicker: NSViewRepresentable {
@Binding var isPresented: Bool
var items: [Any] = []
func makeNSView(context: Context) -> NSView {
let view = NSView()
view.translatesAutoresizingMaskIntoConstraints = false
return view
krzyzanowskim /
Last active Mar 17, 2022
NSResponder.undoManager is not used (FB9959997)

According to documentation it's enough to override NSResponder.undoManager to provide custom NSUndoManager instance. I found it's not quite working:

  • Xcode Mac application template comes with Undo menu item bind to firstResponder.undo: despite NSResponder has no undo: selector defined. Unless first responder actually respond to undo: the Undo action doesn't work
  • NSFirstResponder.undoManager look up in responder chain and eventually it end up in NSWindow where the only place (that I found) that validate Undo menu item is NSWindow.validateUserInterfaceItem - that one, as turned out, only ever validate undo: action if first responder implements _getUndoManager: selector (quite private, isn't it?) - see attached disassembly

at this point 🤕 I start to think it's either documentation issue, or AppKit implementation issue. Anyway, I didn't found way to enable undo: action unless I implement one of these methods in my NSView. (notice: the view is first responder tha

krzyzanowskim / UTF16_to_bytes.swift
Last active Mar 7, 2022
Creates a string from the given bytes in the UTF16 encoding.
View UTF16_to_bytes.swift
extension Array where Element == UInt16 {
/// Little-Endian UTF16 bytes
var bytes: [UInt8] {
flatMap {
UInt8($0.littleEndian & 0xFF),
UInt8(($0.littleEndian &>> 8) & 0xFF)