单词列表页导航栏新增刷新按钮，支持随机重排单词顺序

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

LearnEnglish/LearnEnglish/Models/Word.swift

@@ -15,7 +15,7 @@ struct WordCategory: Codable, Identifiable, Hashable {
 
 struct Subcategory: Codable, Hashable {
     let name: String
-    let words: [Word]
+    var words: [Word]
 }
 
 struct Word: Codable, Identifiable, Hashable {

LearnEnglish/LearnEnglish/Views/WordListViewController.swift

@@ -3,14 +3,22 @@ import UIKit
 final class WordListViewController: UIViewController {
     private let category: WordCategory
     private let colorIndex: Int
+    private var words: [Word]
+    private var subcategories: [Subcategory]?
     private let tableView = UITableView(frame: .zero, style: .plain)
     private let ctaBackground = UIVisualEffectView(effect: UIBlurEffect(style: .systemMaterial))
     private let quizButton = UIButton(type: .system)
     private var speechObserver: NSObjectProtocol?
 
+    private var displaySubcategories: [Subcategory]? {
+        subcategories.flatMap { $0.isEmpty ? nil : $0 }
+    }
+
     init(category: WordCategory, colorIndex: Int) {
         self.category = category
         self.colorIndex = colorIndex
+        self.words = category.words
+        self.subcategories = category.subcategories
         super.init(nibName: nil, bundle: nil)
     }
 
@@ -27,6 +35,12 @@ final class WordListViewController: UIViewController {
         super.viewDidLoad()
         title = category.name
         navigationItem.largeTitleDisplayMode = .never
+        navigationItem.rightBarButtonItem = UIBarButtonItem(
+            image: UIImage(systemName: "arrow.triangle.2.circlepath"),
+            style: .plain,
+            target: self,
+            action: #selector(shuffleWords)
+        )
         view.backgroundColor = .systemBackground
 
         tableView.dataSource = self
@@ -119,16 +133,31 @@ final class WordListViewController: UIViewController {
 
     private func startQuiz() {
         Haptics.selection()
-        let words: [Word]
+        let quizWords: [Word]
         if category.id == "numbers" {
-            words = NumberWords.randomWords(count: 50)
+            quizWords = NumberWords.randomWords(count: 50)
         } else {
-            words = category.words
+            quizWords = words
         }
-        let request = QuizSetupRequest(words: words)
+        let request = QuizSetupRequest(words: quizWords)
         navigationController?.pushViewController(QuizSetupViewController(request: request), animated: true)
     }
 
+    @objc private func shuffleWords() {
+        Haptics.selection()
+        if var subs = subcategories {
+            subs = subs.map { sub in
+                var s = sub
+                s.words = sub.words.shuffled()
+                return s
+            }
+            subcategories = subs
+        } else {
+            words.shuffle()
+        }
+        tableView.reloadData()
+    }
+
     private func updateVisibleSpeakers() {
         for cell in tableView.visibleCells.compactMap({ $0 as? WordCardCell }) {
             cell.updateSpeakerState()
@@ -137,32 +166,28 @@ final class WordListViewController: UIViewController {
 }
 
 extension WordListViewController: UITableViewDataSource, UITableViewDelegate {
-    private var sections: [Subcategory]? {
-        category.subcategories.flatMap { $0.isEmpty ? nil : $0 }
-    }
-
     func numberOfSections(in tableView: UITableView) -> Int {
-        sections?.count ?? 1
+        displaySubcategories?.count ?? 1
     }
 
     func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
-        sections?[section].name
+        displaySubcategories?[section].name
     }
 
     func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
-        if let sections {
-            return sections[section].words.count
+        if let subs = displaySubcategories {
+            return subs[section].words.count
         }
-        return category.words.count
+        return words.count
     }
 
     func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
         let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! WordCardCell
         let word: Word
-        if let sections {
-            word = sections[indexPath.section].words[indexPath.row]
+        if let subs = displaySubcategories {
+            word = subs[indexPath.section].words[indexPath.row]
         } else {
-            word = category.words[indexPath.row]
+            word = words[indexPath.row]
         }
         cell.configure(with: word)
         cell.onSpeak = { word in
@@ -179,10 +204,10 @@ extension WordListViewController: UITableViewDataSource, UITableViewDelegate {
     func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
         Haptics.selection()
         let word: Word
-        if let sections {
-            word = sections[indexPath.section].words[indexPath.row]
+        if let subs = displaySubcategories {
+            word = subs[indexPath.section].words[indexPath.row]
         } else {
-            word = category.words[indexPath.row]
+            word = words[indexPath.row]
         }
         let detail = WordDetailViewController(word: word, categoryName: category.name)
         navigationController?.pushViewController(detail, animated: true)