onevcat

import SwiftUI

struct ContentView: View {
    
    @State var offset: CGFloat = 0.0
    @State var previousOffset: CGFloat = 0.0
    
    init() {
        let appearance = UINavigationBarAppearance()

onevcat

```swift
actor GiftCache {
  private(set) var cachedGifts: [GiftId: CachedGift] = [:]
  
  // this method would be caller by other parts
  func add(gift: CachedGift) {
    cachedGifts[gift.giftId] = gift
    //...
  }
  

onevcat

// https://github.com/pointfreeco/swift-composable-architecture/discussions/488#discussioncomment-591715

@propertyWrapper
public struct CoW<T> {
  private final class Ref {
    var val: T
    init(_ v: T) { val = v }
  }
  private var ref: Ref

onevcat

protocol P: AnyObject { }
class A: P {}

Runtime.classes(conformTo: P.Type.self) // [MyApp.A]

class Runtime {

    public static func allClasses() -> [AnyClass] {
        let numberOfClasses = Int(objc_getClassList(nil, 0))
        if numberOfClasses > 0 {

onevcat

import UIKit

protocol DefaultValue {
    associatedtype Value: Decodable
    static var defaultValue: Value { get }
}

@propertyWrapper
struct Default<T: DefaultValue> {
    var wrappedValue: T.Value

onevcat

//: A UIKit based Playground for presenting user interface
  
import UIKit
import PlaygroundSupport

public protocol TrafficLightOption {
    associatedtype Value

    /// 默认的选项值
    static var defaultValue: Value { get }

onevcat

import Combine
import Foundation

extension Publishers {
    struct ZipAll<Collection: Swift.Collection>: Publisher
    where Collection.Element: Publisher
    {
        typealias Output = [Collection.Element.Output]
        typealias Failure = Collection.Element.Failure

onevcat

用户体验和布局进阶

PokeMaster app 现在已经是一个具有完整功能的 SwiftUI app 了。麻雀虽小，五脏俱全，在这个示例 app 里，我们涉及到了一个一般性的 iOS app 所需要的大部分内容：

• 如何构建内容展示的列表
• 如何构建用户交互的表单
• 如何进行网络请求并把内容展示出来
• 如何响应用户的手势
• 如何在不同页面之间进行导航
• 以及，如何通过一定的架构将所有上面的内容整合起来

onevcat

class CabalInstall < Formula
  desc "Command-line interface for Cabal and Hackage"
  homepage "https://www.haskell.org/cabal/"
  url "https://hackage.haskell.org/package/cabal-install-2.4.1.0/cabal-install-2.4.1.0.tar.gz"
  sha256 "69bcb2b54a064982412e1587c3c5c1b4fada3344b41b568aab25730034cb21ad"
  head "https://github.com/haskell/cabal.git", :branch => "2.4"

  bottle do
    cellar :any_skip_relocation
    sha256 "4c9ad9914b483ffb64f4449bd6446cb8c0ddfeeff42eddde9137884af3471825" => :mojave

onevcat

import Foundation
import Combine

protocol Resumable {
    func resume()
}

extension Subscribers {
    class ResumableSink<Input, Failure: Error>: Subscriber, Cancellable, Resumable {
        let receiveCompletion: (Subscribers.Completion<Failure>) -> Void