Initial commit

.gitignore

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+.DS_Store
+/.build
+/Packages
+/*.xcodeproj
+xcuserdata/
+DerivedData/
+.swiftpm/config/registries.json
+.swiftpm/xcode/package.xcworkspace/contents.xcworkspacedata
+.netrc
+

LICENSE

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+MIT License
+
+Copyright (c) 2024 Colin O'Brien
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

Package.swift

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+// swift-tools-version: 5.7
+import PackageDescription
+
+let package = Package(
+  name: "TypewriterCarouselView",
+  platforms: [
+    .iOS(.v16)
+  ],
+  products: [
+    .library(
+      name: "TypewriterCarouselView",
+      targets: ["TypewriterCarouselView"]
+    )
+  ],
+  dependencies: [],
+  targets: [
+    .target(
+      name: "TypewriterCarouselView",
+      dependencies: []
+    )
+  ]
+)

Sources/TypewriterCarouselView/TypewriterCarouselView.swift

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+//
+//  TypewriterView.swift
+//
+//
+//  Created by Colin O'Brien on 4/04/24.
+//
+
+import SwiftUI
+
+struct TypewriterCarouselView: View {
+
+  @State var text: [String]
+  @State private var currentText: String?
+  @State private var cursor: Int = -1
+
+  var typingDelay: Duration = .milliseconds(50)
+  var onWritingFinishedDelay: Duration = .seconds(5)
+  var onDeletingFinishedDelay: Duration = .seconds(1)
+  var mode: TypewriterView.Mode = .writeAndDelete
+
+  var body: some View {
+    TypewriterView(
+      text: currentText,
+      typingDelay: typingDelay,
+      onTypingFinished: {
+        cursor += 1
+        currentText = text[cursor % text.count]
+      },
+      onWritingFinishedDelay: onWritingFinishedDelay,
+      onDeletingFinishedDelay: onDeletingFinishedDelay,
+      mode: mode
+    )
+    .font(.title)
+    .padding()
+  }
+}
+
+#Preview {
+  TypewriterCarouselView(text: ["Hello", "World!"])
+}

Sources/TypewriterCarouselView/TypewriterView.swift

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+//
+//  TypewriterView.swift
+//
+//
+//  Created by Colin O'Brien on 4/04/24.
+//
+
+import SwiftUI
+
+struct TypewriterView: View {
+
+  enum Mode {
+    case write, writeAndDelete
+  }
+
+  var text: String?
+  var typingDelay: Duration = .milliseconds(50)
+  var onTypingFinished: (() -> Void) = {}
+  var onWritingFinishedDelay: Duration = .seconds(5)
+  var onDeletingFinishedDelay: Duration = .seconds(1)
+  var mode: Mode = .writeAndDelete
+
+  @State private var animatedText: AttributedString = ""
+  @State private var typingTask: Task<Void, Error>?
+
+  var body: some View {
+    Text(animatedText)
+      .onChange(of: text, perform: { _ in animateText() })
+      .onAppear { animateText() }
+  }
+
+  private func animateText() {
+    typingTask?.cancel()
+
+    guard let text = text else {
+      onTypingFinished()
+      return
+    }
+
+    typingTask = Task {
+      let defaultAttributes = AttributeContainer()
+      animatedText = AttributedString(
+        text,
+        attributes: defaultAttributes.foregroundColor(.clear)
+      )
+
+      var index = animatedText.startIndex
+      while index < animatedText.endIndex {
+        try Task.checkCancellation()
+
+        // Update the style
+        animatedText[animatedText.startIndex...index]
+          .setAttributes(defaultAttributes)
+
+        // Wait
+        try await Task.sleep(for: typingDelay)
+
+        // Advance the index, character by character
+        index = animatedText.index(afterCharacter: index)
+      }
+
+      // Wait
+      try await Task.sleep(for: onWritingFinishedDelay)
+
+      switch mode {
+      case .write: onTypingFinished()
+
+      case .writeAndDelete:
+        index = animatedText.endIndex
+
+        while index > animatedText.startIndex {
+          try Task.checkCancellation()
+
+          animatedText[index..<animatedText.endIndex]
+            .setAttributes(defaultAttributes.foregroundColor(.clear))
+
+          try await Task.sleep(for: typingDelay)
+
+          index = animatedText.index(beforeCharacter: index)
+        }
+
+        animatedText.setAttributes(defaultAttributes.foregroundColor(.clear))
+
+        try await Task.sleep(for: onDeletingFinishedDelay)
+
+        onTypingFinished()
+      }
+    }
+  }
+}
+
+#Preview {
+  TypewriterView(text: "Hello World!")
+}