Merge pull request #57 from componentskit/UKBadge

UKBadge

Author: mikhailChelbaev

Examples/DemosApp/DemosApp/ComponentsPreview/PreviewPages/BadgePreview.swift

@@ -9,6 +9,10 @@ struct BadgePreview: View {
 
   var body: some View {
     VStack {
+      PreviewWrapper(title: "UIKit") {
+        UKBadge(model: self.model)
+          .preview
+      }
       PreviewWrapper(title: "SwiftUI") {
         SUBadge(model: self.model)
       }
@@ -28,6 +32,14 @@ struct BadgePreview: View {
           Text("Filled").tag(BadgeVM.Style.filled)
           Text("Light").tag(BadgeVM.Style.light)
         }
+        Picker("Paddings", selection: self.$model.paddings) {
+          Text("8px; 6px")
+            .tag(Paddings(top: 6, leading: 8, bottom: 6, trailing: 8))
+          Text("10px; 8px")
+            .tag(Paddings(top: 8, leading: 10, bottom: 8, trailing: 10))
+          Text("12px; 10px")
+            .tag(Paddings(top: 10, leading: 12, bottom: 10, trailing: 12))
+        }
       }
     }
   }

Sources/ComponentsKit/Components/Badge/Models/BadgeVM.swift

@@ -53,3 +53,12 @@ extension BadgeVM {
     }
   }
 }
+
+// MARK: UIKit Helpers
+
+extension BadgeVM {
+  func shouldUpdateLayout(_ oldModel: Self?) -> Bool {
+    return self.font != oldModel?.font
+    || self.paddings != oldModel?.paddings
+  }
+}

Sources/ComponentsKit/Components/Badge/UKBadge.swift

@@ -0,0 +1,127 @@
+import AutoLayout
+import UIKit
+
+/// A UIKit component that displays a badge.
+open class UKBadge: UIView, UKComponent {
+  // MARK: - Properties
+
+  /// A model that defines the appearance properties.
+  public var model: BadgeVM {
+    didSet {
+      self.update(oldValue)
+    }
+  }
+
+  private var titleLabelConstraints: LayoutConstraints = .init()
+
+  // MARK: - Subviews
+
+  /// A label that displays the title from the model.
+  public var titleLabel = UILabel()
+
+  // MARK: - UIView Properties
+
+  open override var intrinsicContentSize: CGSize {
+    return self.sizeThatFits(UIView.layoutFittingExpandedSize)
+  }
+
+  // MARK: - Initialization
+
+  /// Initializes a new instance of `UKBadge`.
+  /// - Parameter model: A model that defines the appearance properties for the badge.
+  public init(model: BadgeVM = .init()) {
+    self.model = model
+    super.init(frame: .zero)
+
+    self.setup()
+    self.style()
+    self.layout()
+  }
+
+  public required init?(coder: NSCoder) {
+    fatalError("init(coder:) has not been implemented")
+  }
+
+  // MARK: - Setup
+
+  private func setup() {
+    self.addSubview(self.titleLabel)
+  }
+
+  // MARK: - Style
+
+  private func style() {
+    Self.Style.mainView(self, model: self.model)
+    Self.Style.titleLabel(self.titleLabel, model: self.model)
+  }
+
+  // MARK: - Layout
+
+  private func layout() {
+    self.titleLabelConstraints = .merged {
+      self.titleLabel.top(self.model.paddings.top)
+      self.titleLabel.leading(self.model.paddings.leading)
+      self.titleLabel.bottom(self.model.paddings.bottom)
+      self.titleLabel.trailing(self.model.paddings.trailing)
+    }
+
+    self.titleLabelConstraints.allConstraints.forEach { $0?.priority = .defaultHigh }
+  }
+
+  open override func layoutSubviews() {
+    super.layoutSubviews()
+
+    self.layer.cornerRadius = self.model.cornerRadius.value(for: self.bounds.height)
+  }
+
+  // MARK: - Update
+
+  public func update(_ oldModel: BadgeVM) {
+    guard self.model != oldModel else { return }
+
+    self.style()
+    if self.model.shouldUpdateLayout(oldModel) {
+      self.titleLabelConstraints.leading?.constant = self.model.paddings.leading
+      self.titleLabelConstraints.top?.constant = self.model.paddings.top
+      self.titleLabelConstraints.bottom?.constant = -self.model.paddings.bottom
+      self.titleLabelConstraints.trailing?.constant = -self.model.paddings.trailing
+
+      self.invalidateIntrinsicContentSize()
+      self.setNeedsLayout()
+    }
+  }
+
+  // MARK: - UIView Methods
+
+  open override func sizeThatFits(_ size: CGSize) -> CGSize {
+    let contentSize = self.titleLabel.sizeThatFits(size)
+
+    let totalWidthPadding = self.model.paddings.leading + self.model.paddings.trailing
+    let totalHeightPadding = self.model.paddings.top + self.model.paddings.bottom
+
+    let width = contentSize.width + totalWidthPadding
+    let height = contentSize.height + totalHeightPadding
+
+    return CGSize(
+      width: min(width, size.width),
+      height: min(height, size.height)
+    )
+  }
+}
+
+// MARK: - Style Helpers
+
+extension UKBadge {
+  fileprivate enum Style {
+    static func mainView(_ view: UIView, model: BadgeVM) {
+      view.backgroundColor = model.backgroundColor.uiColor
+      view.layer.cornerRadius = model.cornerRadius.value(for: view.bounds.height)
+    }
+    static func titleLabel(_ label: UILabel, model: BadgeVM) {
+      label.textAlignment = .center
+      label.text = model.title
+      label.font = model.font.uiFont
+      label.textColor = model.foregroundColor.uiColor
+    }
+  }
+}