拼写改为确认按钮手动提交，点击已填字母可删除重输

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

LearnEnglish/LearnEnglish/Views/SpellingInputView.swift

@@ -1,7 +1,7 @@
 import UIKit
 
 final class SpellingInputView: UIView, UITextFieldDelegate {
-    var onComplete: ((String) -> Void)?
+    var onChange: (() -> Void)?
 
     private let hiddenField = UITextField()
     private let stack = UIStackView()
@@ -9,16 +9,21 @@ final class SpellingInputView: UIView, UITextFieldDelegate {
     private var chars: [String] = []
     private var blankPositions: [Int] = []
     private var filledBlanks: [String] = []
-    private var currentBlankIndex = 0
+    private var cursorIndex = 0
     private var boxViews: [UIView] = []
     private var cursorView: UIView?
     private var inputEnabled = true
 
+    var isComplete: Bool {
+        !filledBlanks.isEmpty && filledBlanks.allSatisfy { !$0.isEmpty }
+    }
+
     override init(frame: CGRect) {
         super.init(frame: frame)
         stack.axis = .horizontal
         stack.spacing = 6
         stack.alignment = .center
+        stack.isUserInteractionEnabled = true
         addSubview(stack)
         stack.translatesAutoresizingMaskIntoConstraints = false
         NSLayoutConstraint.activate([
@@ -47,11 +52,19 @@ final class SpellingInputView: UIView, UITextFieldDelegate {
         chars = blankedWord.map { String($0) }
         self.blankPositions = blankPositions
         filledBlanks = Array(repeating: "", count: blankPositions.count)
-        currentBlankIndex = 0
+        cursorIndex = 0
         inputEnabled = true
         rebuildBoxes()
     }
 
+    func typedWord() -> String {
+        var rebuilt = chars
+        for (i, pos) in blankPositions.enumerated() {
+            rebuilt[pos] = filledBlanks[i]
+        }
+        return rebuilt.joined().lowercased()
+    }
+
     func activate() {
         guard inputEnabled, !hiddenField.isFirstResponder else { return }
         hiddenField.becomeFirstResponder()
@@ -72,22 +85,17 @@ final class SpellingInputView: UIView, UITextFieldDelegate {
     func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
         guard inputEnabled else { return false }
         if string.isEmpty {
-            if currentBlankIndex > 0 {
-                currentBlankIndex -= 1
-                filledBlanks[currentBlankIndex] = ""
+            if cursorIndex > 0 {
+                cursorIndex -= 1
+                filledBlanks[cursorIndex] = ""
                 refreshBoxes()
+                onChange?()
             }
-        } else if let char = string.last, char.isLetter, currentBlankIndex < blankPositions.count {
-            filledBlanks[currentBlankIndex] = String(char).lowercased()
-            currentBlankIndex += 1
+        } else if let char = string.last, char.isLetter, cursorIndex < blankPositions.count {
+            filledBlanks[cursorIndex] = String(char).lowercased()
+            cursorIndex += 1
             refreshBoxes()
-            if currentBlankIndex == blankPositions.count {
-                var rebuilt = chars
-                for (i, pos) in blankPositions.enumerated() {
-                    rebuilt[pos] = filledBlanks[i]
-                }
-                onComplete?(rebuilt.joined().lowercased())
-            }
+            onChange?()
         }
         textField.text = nil
         return false
@@ -99,10 +107,12 @@ final class SpellingInputView: UIView, UITextFieldDelegate {
         stack.arrangedSubviews.forEach { $0.removeFromSuperview() }
         boxViews = chars.enumerated().map { index, ch in
             let box = makeBox()
-            if ch != "_", let label = box.subviews.compactMap({ $0 as? UILabel }).first {
+            box.tag = index
+            if ch != "_", let label = box.viewWithTag(100) as? UILabel {
                 label.text = ch.uppercased()
                 label.isHidden = false
             }
+            box.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(boxTapped(_:))))
             stack.addArrangedSubview(box)
             NSLayoutConstraint.activate([
                 box.widthAnchor.constraint(equalToConstant: 36),
@@ -113,6 +123,20 @@ final class SpellingInputView: UIView, UITextFieldDelegate {
         refreshBoxes()
     }
 
+    @objc private func boxTapped(_ gesture: UITapGestureRecognizer) {
+        guard inputEnabled, let box = gesture.view else { return }
+        let index = box.tag
+        guard chars[index] == "_", let blankIndex = blankPositions.firstIndex(of: index) else {
+            activate()
+            return
+        }
+        filledBlanks[blankIndex] = ""
+        cursorIndex = blankIndex
+        refreshBoxes()
+        onChange?()
+        activate()
+    }
+
     private func makeBox() -> UIView {
         let box = UIView()
         box.backgroundColor = .quaternarySystemFill.withAlphaComponent(0.15)
@@ -147,13 +171,14 @@ final class SpellingInputView: UIView, UITextFieldDelegate {
             label?.text = filled.uppercased()
             label?.isHidden = filled.isEmpty
 
-            let isCurrent = inputEnabled && blankIndex == currentBlankIndex
+            let isCurrent = inputEnabled && blankIndex == cursorIndex
             box.layer.borderColor = isCurrent ? UIColor.tintColor.cgColor : UIColor.separator.cgColor
             box.layer.borderWidth = isCurrent ? 2 : 1
 
             if isCurrent, filled.isEmpty {
                 let cursor = UIView()
                 cursor.backgroundColor = .tintColor
+                cursor.isUserInteractionEnabled = false
                 box.addSubview(cursor)
                 cursor.translatesAutoresizingMaskIntoConstraints = false
                 NSLayoutConstraint.activate([