Merge pull request #60 from componentskit/UKAvatar

UKAvatar

Author: mikhailChelbaev

Examples/DemosApp/DemosApp/ComponentsPreview/PreviewPages/AvatarPreview.swift

@@ -9,6 +9,10 @@ struct AvatarPreview: View {
 
   var body: some View {
     VStack {
+      PreviewWrapper(title: "UIKit") {
+        UKAvatar(model: self.model)
+          .preview
+      }
       PreviewWrapper(title: "SwiftUI") {
         SUAvatar(model: self.model)
       }

Sources/ComponentsKit/Components/Avatar/Helpers/AvatarImageManager.swift

@@ -0,0 +1,57 @@
+import SwiftUI
+import UIKit
+
+final class AvatarImageManager: ObservableObject {
+  @Published var avatarImage: UIImage
+
+  private var model: AvatarVM
+  private static var remoteImagesCache = NSCache<NSString, UIImage>()
+
+  init(model: AvatarVM) {
+    self.model = model
+
+    let size = model.preferredSize
+    switch model.imageSrc {
+    case .remote(let url):
+      self.avatarImage = model.placeholderImage(for: size)
+      self.downloadImage(url: url)
+    case let .local(name, bundle):
+      self.avatarImage = UIImage(named: name, in: bundle, compatibleWith: nil) ?? model.placeholderImage(for: size)
+    case .none:
+      self.avatarImage = model.placeholderImage(for: size)
+    }
+  }
+
+  func update(model: AvatarVM, size: CGSize) {
+    self.model = model
+
+    switch model.imageSrc {
+    case .remote(let url):
+      if let image = Self.remoteImagesCache.object(forKey: url.absoluteString as NSString) {
+        self.avatarImage = image
+      } else {
+        self.avatarImage = model.placeholderImage(for: size)
+        self.downloadImage(url: url)
+      }
+    case let .local(name, bundle):
+      self.avatarImage = UIImage(named: name, in: bundle, compatibleWith: nil) ?? model.placeholderImage(for: size)
+    case .none:
+      self.avatarImage = model.placeholderImage(for: size)
+    }
+  }
+
+  private func downloadImage(url: URL) {
+    Task { @MainActor in
+      let request = URLRequest(url: url)
+      guard let (data, _) = try? await URLSession.shared.data(for: request),
+            let image = UIImage(data: data)
+      else { return }
+
+      Self.remoteImagesCache.setObject(image, forKey: url.absoluteString as NSString)
+
+      if url == self.model.imageURL {
+        self.avatarImage = image
+      }
+    }
+  }
+}

Sources/ComponentsKit/Components/Avatar/Helpers/ImageLoader.swift

@@ -7,7 +7,8 @@ public struct SUAvatar: View {
   /// A model that defines the appearance properties.
   public var model: AvatarVM
 
-  @State private var loadedImage: (url: URL, image: UIImage)?
+  @StateObject private var imageManager: AvatarImageManager
+  @Environment(\.colorScheme) private var colorScheme
 
   // MARK: - Initialization
 
@@ -16,71 +17,29 @@ public struct SUAvatar: View {
   ///   - model: A model that defines the appearance properties.
   public init(model: AvatarVM) {
     self.model = model
+    self._imageManager = StateObject(
+      wrappedValue: AvatarImageManager(model: model)
+    )
   }
 
   // MARK: - Body
 
   public var body: some View {
-    Group {
-      switch self.model.imageSrc {
-      case .remote:
-        if let loadedImage {
-          Image(uiImage: loadedImage.image)
-            .resizable()
-            .transition(.opacity)
-        } else {
-          self.placeholder
-        }
-      case let .local(name, bundle):
-        Image(name, bundle: bundle)
-          .resizable()
-      case .none:
-        self.placeholder
-      }
-    }
-    .aspectRatio(contentMode: .fill)
-    .frame(
-      width: self.model.preferredSize.width,
-      height: self.model.preferredSize.height
-    )
-    .clipShape(
-      RoundedRectangle(cornerRadius: self.model.cornerRadius.value())
-    )
-    .onAppear {
-      if let imageURL = self.model.imageURL {
-        self.downloadImage(url: imageURL)
-      }
-    }
-    .onChange(of: self.model.imageSrc) { newValue in
-      switch newValue {
-      case .remote(let url):
-        self.downloadImage(url: url)
-      case .local, .none:
-        break
-      }
-    }
-  }
-
-  // MARK: - Subviews
-
-  private var placeholder: some View {
-    Image(uiImage: self.model.placeholderImage(
-      for: self.model.preferredSize
-    ))
+    Image(uiImage: self.imageManager.avatarImage)
       .resizable()
-  }
-
-  // MARK: - Helpers
-
-  private func downloadImage(url: URL) {
-    guard self.loadedImage?.url != url else { return }
-
-    self.loadedImage = nil
-    Task { @MainActor in
-      guard let image = await ImageLoader.download(url: url) else { return }
-      withAnimation {
-        self.loadedImage = (url, image)
+      .aspectRatio(contentMode: .fill)
+      .frame(
+        width: self.model.preferredSize.width,
+        height: self.model.preferredSize.height
+      )
+      .clipShape(
+        RoundedRectangle(cornerRadius: self.model.cornerRadius.value())
+      )
+      .onChange(of: self.model) { newValue in
+        self.imageManager.update(model: newValue, size: newValue.preferredSize)
+      }
+      .onChange(of: self.colorScheme) { _ in
+        self.imageManager.update(model: self.model, size: self.model.preferredSize)
       }
-    }
   }
 }

Sources/ComponentsKit/Components/Avatar/SUAvatar.swift

@@ -0,0 +1,118 @@
+import Combine
+import UIKit
+
+/// A UIKit component that displays a profile picture, initials or fallback icon for a user.
+open class UKAvatar: UIImageView, UKComponent {
+  // MARK: - Properties
+
+  /// A model that defines the appearance properties.
+  public var model: AvatarVM {
+    didSet {
+      self.update(oldValue)
+    }
+  }
+
+  private let imageManager: AvatarImageManager
+  private var cancellable: AnyCancellable?
+
+  // MARK: - UIView Properties
+
+  open override var intrinsicContentSize: CGSize {
+    return self.model.preferredSize
+  }
+
+  // MARK: - Initialization
+
+  /// Initializer.
+  /// - Parameters:
+  ///   - model: A model that defines the appearance properties.
+  public init(model: AvatarVM = .init()) {
+    self.model = model
+    self.imageManager = AvatarImageManager(model: model)
+
+    super.init(frame: .zero)
+
+    self.setup()
+    self.style()
+  }
+
+  public required init?(coder: NSCoder) {
+    fatalError("init(coder:) has not been implemented")
+  }
+
+  // MARK: - Deinitialization
+
+  deinit {
+    self.cancellable?.cancel()
+    self.cancellable = nil
+  }
+
+  // MARK: - Setup
+
+  private func setup() {
+    self.cancellable = self.imageManager.$avatarImage
+      .receive(on: DispatchQueue.main)
+      .sink { self.image = $0 }
+
+    if #available(iOS 17.0, *) {
+      self.registerForTraitChanges([UITraitUserInterfaceStyle.self]) { (view: Self, _: UITraitCollection) in
+        view.handleTraitChanges()
+      }
+    }
+  }
+
+  // MARK: - Style
+
+  private func style() {
+    self.contentMode = .scaleToFill
+    self.clipsToBounds = true
+  }
+
+  // MARK: - Update
+
+  public func update(_ oldModel: AvatarVM) {
+    guard self.model != oldModel else { return }
+
+    self.imageManager.update(model: self.model, size: self.bounds.size)
+
+    if self.model.cornerRadius != oldModel.cornerRadius {
+      self.layer.cornerRadius = self.model.cornerRadius.value(for: self.bounds.height)
+    }
+    if self.model.size != oldModel.size {
+      self.setNeedsLayout()
+      self.invalidateIntrinsicContentSize()
+    }
+  }
+
+  // MARK: - Layout
+
+  open override func layoutSubviews() {
+    super.layoutSubviews()
+
+    self.layer.cornerRadius = self.model.cornerRadius.value(for: self.bounds.height)
+
+    self.imageManager.update(model: self.model, size: self.bounds.size)
+  }
+
+  // MARK: - UIView Methods
+
+  open override func sizeThatFits(_ size: CGSize) -> CGSize {
+    let minProvidedSide = min(size.width, size.height)
+    let minPreferredSide = min(self.model.preferredSize.width, self.model.preferredSize.height)
+    let side = min(minProvidedSide, minPreferredSide)
+    return CGSize(width: side, height: side)
+  }
+
+  open override func traitCollectionDidChange(
+    _ previousTraitCollection: UITraitCollection?
+  ) {
+    super.traitCollectionDidChange(previousTraitCollection)
+    self.handleTraitChanges()
+  }
+
+  // MARK: Helpers
+
+  @objc private func handleTraitChanges() {
+    self.imageManager.update(model: self.model, size: self.bounds.size)
+  }
+}

Sources/ComponentsKit/Components/Avatar/UKAvatar.swift

@@ -32,7 +32,7 @@ open class UKDivider: UIView, UKComponent {
     fatalError("init(coder:) has not been implemented")
   }
 
-  // MARK: - Setup
+  // MARK: - Style
 
   private func style() {
     self.backgroundColor = self.model.lineColor.uiColor