单词列表卡片增加学习按钮，点击跳转拼写练习

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

LearnEnglish/LearnEnglish/Models/Quiz.swift

@@ -70,9 +70,9 @@ enum QuizGenerator {
     private static func blankWord(_ word: String) -> String {
         let chars = Array(word)
         let letterPositions = chars.indices.filter { chars[$0].isLetter }
-        guard letterPositions.count > 2 else { return String(repeating: "_", count: chars.count) }
+        guard !letterPositions.isEmpty else { return word }
-        let blanks = max(1, Int(Double(letterPositions.count) * 0.4))
+        let blankCount = min(letterPositions.count - 1, Int(ceil(Double(letterPositions.count) * 0.4)))
-        let indices = Set(letterPositions.shuffled().prefix(blanks))
+        let indices = Set(letterPositions.shuffled().prefix(blankCount))
         return chars.enumerated().map { indices.contains($0.offset) ? "_" : String($0.element) }.joined()
     }
 }

LearnEnglish/LearnEnglish/Views/QuizViewController.swift

@@ -21,9 +21,11 @@ final class QuizViewController: UIViewController {
     private let spellingHintLabel = UILabel()
     private let resultLabel = UILabel()
     private let resultPhoneticLabel = UILabel()
+    private let countdownLabel = UILabel()
     private let nextButton = UIButton(type: .system)
     private var optionButtons: [UIButton] = []
     private var optionIcons: [UIImageView] = []
+    private var countdownTimer: Timer?
 
     private let promptStack = UIStackView()
     private let inputStack = UIStackView()
@@ -48,6 +50,10 @@ final class QuizViewController: UIViewController {
     @available(*, unavailable)
     required init?(coder: NSCoder) { fatalError() }
 
+    deinit {
+        countdownTimer?.invalidate()
+    }
+
     override func viewDidLoad() {
         super.viewDidLoad()
         view.backgroundColor = .systemBackground
@@ -135,7 +141,11 @@ final class QuizViewController: UIViewController {
 
         resultStack.axis = .vertical
         resultStack.spacing = 12
-        [resultLabel, resultPhoneticLabel, nextButton].forEach { resultStack.addArrangedSubview($0) }
+        countdownLabel.font = .preferredFont(forTextStyle: .caption1)
+        countdownLabel.textColor = .tertiaryLabel
+        countdownLabel.textAlignment = .center
+        countdownLabel.isHidden = true
+        [resultLabel, resultPhoneticLabel, countdownLabel, nextButton].forEach { resultStack.addArrangedSubview($0) }
 
         let mainStack = UIStackView(arrangedSubviews: [headerStack, promptStack, inputStack, resultStack, UIView()])
         mainStack.axis = .vertical
@@ -358,6 +368,18 @@ final class QuizViewController: UIViewController {
         if config.isStudyMode {
             nextButton.isHidden = true
             let delay: TimeInterval = correct ? 1.0 : 3.0
+            countdownLabel.text = "\(Int(delay)) 秒后继续"
+            countdownLabel.isHidden = false
+            countdownTimer?.invalidate()
+            var remaining = Int(delay)
+            countdownTimer = Timer.scheduledTimer(withTimeInterval: 1, repeats: true) { [weak self] timer in
+                remaining -= 1
+                if remaining > 0 {
+                    self?.countdownLabel.text = "\(remaining) 秒后继续"
+                } else {
+                    timer.invalidate()
+                }
+            }
             DispatchQueue.main.asyncAfter(deadline: .now() + delay) { [weak self] in
                 self?.restart()
             }
@@ -440,6 +462,8 @@ final class QuizViewController: UIViewController {
     }
 
     private func restart() {
+        countdownTimer?.invalidate()
+        countdownLabel.isHidden = true
         view.subviews.compactMap { $0 as? QuizResultView }.forEach { $0.removeFromSuperview() }
         questions = QuizGenerator.makeQuestions(mode: config.mode, words: config.words)
         currentIndex = 0

LearnEnglish/LearnEnglish/Views/WordCardCell.swift

@@ -5,10 +5,12 @@ final class WordCardCell: UITableViewCell {
     private let wordLabel = UILabel()
     private let phoneticLabel = UILabel()
     private let meaningLabel = UILabel()
+    private let learnButton = UIButton(type: .system)
     private let speakerButton = UIButton(type: .system)
     private var word: Word?
 
     var onSpeak: ((Word) -> Void)?
+    var onLearn: ((Word) -> Void)?
 
     var zoomSourceView: UIView { cardView }
 
@@ -39,6 +41,15 @@ final class WordCardCell: UITableViewCell {
         textStack.axis = .vertical
         textStack.spacing = 8
 
+        learnButton.setImage(UIImage(systemName: "book",
+                                     withConfiguration: UIImage.SymbolConfiguration(pointSize: 15, weight: .medium)),
+                             for: .normal)
+        learnButton.tintColor = Theme.Color.accent
+        learnButton.addAction(UIAction { [weak self] _ in
+            guard let self, let word else { return }
+            onLearn?(word)
+        }, for: .touchUpInside)
+
         speakerButton.tintColor = Theme.Color.accent
         speakerButton.addAction(UIAction { [weak self] _ in
             guard let self, let word else { return }
@@ -46,7 +57,7 @@ final class WordCardCell: UITableViewCell {
         }, for: .touchUpInside)
         speakerButton.setContentHuggingPriority(.required, for: .horizontal)
 
-        let row = UIStackView(arrangedSubviews: [textStack, speakerButton])
+        let row = UIStackView(arrangedSubviews: [textStack, learnButton, speakerButton])
         row.axis = .horizontal
         row.alignment = .center
         row.spacing = 8
@@ -57,6 +68,8 @@ final class WordCardCell: UITableViewCell {
             row.leadingAnchor.constraint(equalTo: cardView.leadingAnchor, constant: 14),
             row.trailingAnchor.constraint(equalTo: cardView.trailingAnchor, constant: -8),
             row.bottomAnchor.constraint(equalTo: cardView.bottomAnchor, constant: -10),
+            learnButton.widthAnchor.constraint(equalToConstant: 44),
+            learnButton.heightAnchor.constraint(equalToConstant: 44),
             speakerButton.widthAnchor.constraint(equalToConstant: 44),
             speakerButton.heightAnchor.constraint(equalToConstant: 44)
         ])

LearnEnglish/LearnEnglish/Views/WordListViewController.swift

@@ -148,6 +148,11 @@ extension WordListViewController: UITableViewDataSource, UITableViewDelegate {
         cell.onSpeak = { word in
             SpeechService.shared.speak(word.word)
         }
+        cell.onLearn = { [weak self] word in
+            guard let self else { return }
+            let config = QuizConfig(mode: .spelling, words: [word], isStudyMode: true)
+            navigationController?.pushViewController(QuizViewController(config: config), animated: true)
+        }
         return cell
     }