拼写学习模式改用键盘完成键提交，移除玻璃按钮

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

LearnEnglish/LearnEnglish/Views/SpellingInputView.swift

@@ -3,7 +3,6 @@ import UIKit
 final class SpellingInputView: UIView, UITextFieldDelegate {
     var onChange: (() -> Void)?
     var onSubmit: (() -> Void)?
-    private(set) var confirmButton: UIButton?
 
     private let hiddenField = UITextField()
     private let stack = UIStackView()
@@ -55,39 +54,10 @@ final class SpellingInputView: UIView, UITextFieldDelegate {
         hiddenField.autocapitalizationType = .none
         hiddenField.spellCheckingType = .no
         hiddenField.keyboardType = .asciiCapable
+        hiddenField.returnKeyType = .done
         hiddenField.frame = .zero
         addSubview(hiddenField)
 
-        let accessory = UIView()
-        accessory.frame = CGRect(x: 0, y: 0, width: 0, height: 74)
-        accessory.autoresizingMask = .flexibleWidth
-        accessory.backgroundColor = .clear
-
-        var glassConfig = UIButton.Configuration.glass()
-        glassConfig.title = "确认"
-        glassConfig.cornerStyle = .fixed
-        glassConfig.background.cornerRadius = 25
-        glassConfig.baseForegroundColor = .label
-        glassConfig.titleTextAttributesTransformer = UIConfigurationTextAttributesTransformer { incoming in
-            var outgoing = incoming
-            outgoing.font = .systemFont(ofSize: 16, weight: .semibold)
-            return outgoing
-        }
-        let glassButton = UIButton(configuration: glassConfig)
-        confirmButton = glassButton
-        glassButton.addAction(UIAction { [weak self] _ in
-            self?.onSubmit?()
-        }, for: .touchUpInside)
-        glassButton.translatesAutoresizingMaskIntoConstraints = false
-        accessory.addSubview(glassButton)
-        NSLayoutConstraint.activate([
-            glassButton.trailingAnchor.constraint(equalTo: accessory.trailingAnchor, constant: -15),
-            glassButton.topAnchor.constraint(equalTo: accessory.topAnchor, constant: 12),
-            glassButton.widthAnchor.constraint(equalToConstant: 80),
-            glassButton.heightAnchor.constraint(equalToConstant: 50)
-        ])
-        hiddenField.inputAccessoryView = accessory
-
         addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(reactivate)))
     }
 
@@ -127,11 +97,6 @@ final class SpellingInputView: UIView, UITextFieldDelegate {
         refreshBoxes()
     }
 
-    func hideAccessoryView() {
-        confirmButton?.isHidden = true
-        hiddenField.inputAccessoryView = nil
-    }
-
     func showResultState(correct: Bool) {
         let color = correct ? Theme.Color.correct : Theme.Color.wrong
         for position in blankPositions {
@@ -178,6 +143,12 @@ final class SpellingInputView: UIView, UITextFieldDelegate {
         return false
     }
 
+    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
+        guard isComplete else { return false }
+        onSubmit?()
+        return false
+    }
+
     // MARK: - Boxes
 
     private func rebuildBoxes() {