Add swipe gestures to Anki-Mode

ios/AnswerTextField.swift

@@ -53,4 +53,19 @@ class AnswerTextField: UITextField {
     }
     return super.textInputMode
   }
+
+  // Add a property to toggle interaction. Doing this will allow the textfield to process events,
+  // which is impossible when simply set to disabled.
+  var isInteractive: Bool = true {
+    didSet {
+      // Dismiss the keyboard if the field is no longer interactive
+      if !isInteractive && isFirstResponder {
+        resignFirstResponder()
+      }
+    }
+  }
+
+  override func becomeFirstResponder() -> Bool {
+    isInteractive ? super.becomeFirstResponder() : false
+  }
 }

ios/ReviewSettingsViewController.swift

@@ -185,6 +185,18 @@ class ReviewSettingsViewController: UITableViewController, TKMViewController {
     ankiModeCombineReadingMeaningIndexPath = model.add(ankiModeCombineReadingMeaning,
                                                        hidden:!Settings.ankiMode)
 
+    let ankiModeSwipeGestures = SwitchModelItem(style: .subtitle,
+                                                title: "Enable swipe gestures",
+                                                subtitle: "Use swipes for marking reviews with Anki mode enabled",
+                                                on: Settings
+                                                  .ankiModeEnableSwipeGestures) { [
+      unowned self
+    ] in
+      ankiModeSwipeGesturesSwitchChanged($0)
+    }
+    ankiModeCombineReadingMeaningIndexPath = model.add(ankiModeSwipeGestures,
+                                                       hidden:!Settings.ankiMode)
+
     model.add(section: "Audio")
     model.add(SwitchModelItem(style: .subtitle,
                               title: "Play audio automatically",
@@ -354,6 +366,10 @@ class ReviewSettingsViewController: UITableViewController, TKMViewController {
     Settings.ankiModeCombineReadingMeaning = switchView.isOn
   }
 
+  private func ankiModeSwipeGesturesSwitchChanged(_ switchView: UISwitch) {
+    Settings.ankiModeEnableSwipeGestures = switchView.isOn
+  }
+
   private func playAudioAutomaticallySwitchChanged(_ switchView: UISwitch) {
     Settings.playAudioAutomatically = switchView.isOn
   }

ios/ReviewViewController.swift

@@ -159,7 +159,8 @@ protocol ReviewViewControllerDelegate: AnyObject {
                                        menuButton: UIButton)
 }
 
-class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelegate {
+class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelegate,
+  SwipeableContainerDelegate {
   private var kanaInput: TKMKanaInput!
   private let hapticGenerator = UIImpactFeedbackGenerator(style: UIImpactFeedbackGenerator
     .FeedbackStyle.light)
@@ -185,6 +186,8 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
 
   private var isPracticeSession = false
 
+  private var swipeContainer: SwipeableContainer!
+
   // These are set to match the keyboard animation.
   private var animationDuration: Double = kDefaultAnimationDuration
   private var animationCurve: UIView.AnimationCurve = kDefaultAnimationCurve
@@ -302,21 +305,40 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
 
     questionLabel.isUserInteractionEnabled = false
 
-    let shortPressRecognizer =
-      UITapGestureRecognizer(target: self, action: #selector(didShortPressQuestionLabel))
-    questionBackground.addGestureRecognizer(shortPressRecognizer)
+    // set up swipe gestures for answering
+    swipeContainer = SwipeableContainer()
+    swipeContainer.delegate = self
+    swipeContainer.translatesAutoresizingMaskIntoConstraints = false
+    view.insertSubview(swipeContainer, belowSubview: promptBackground)
+
+    // Add constraints to match question background
+    NSLayoutConstraint.activate([
+      swipeContainer.leadingAnchor.constraint(equalTo: questionBackground.leadingAnchor),
+      swipeContainer.trailingAnchor.constraint(equalTo: questionBackground.trailingAnchor),
+      swipeContainer.topAnchor.constraint(equalTo: questionBackground.topAnchor),
+      swipeContainer.bottomAnchor.constraint(equalTo: questionBackground.bottomAnchor),
+    ])
+
+    // font cycling tap recognizers
+    func setupTapQuestionRecognizer(numberOfTapsRequired: Int = 1) -> UITapGestureRecognizer {
+      let tapRecognizer = UITapGestureRecognizer(target: self,
+                                                 action: #selector(didTapQuestionView))
+      swipeContainer.addGestureRecognizer(tapRecognizer)
+      tapRecognizer.numberOfTapsRequired = numberOfTapsRequired
+      return tapRecognizer
+    }
+
+    let singleTapRecognizer = setupTapQuestionRecognizer()
+    let doubleTapRecognizer = setupTapQuestionRecognizer(numberOfTapsRequired: 2)
+    let tripleTapRecognizer = setupTapQuestionRecognizer(numberOfTapsRequired: 3)
 
-    let leftSwipeRecognizer = UISwipeGestureRecognizer(target: self,
-                                                       action: #selector(didSwipeQuestionLabel))
-    leftSwipeRecognizer.direction = .left
-    questionBackground.addGestureRecognizer(leftSwipeRecognizer)
-    let rightSwipeRecognizer = UISwipeGestureRecognizer(target: self,
-                                                        action: #selector(didSwipeQuestionLabel))
-    rightSwipeRecognizer.direction = .right
-    questionBackground.addGestureRecognizer(rightSwipeRecognizer)
+    // make sure to fail the tap gesture recognizers with less taps
+    singleTapRecognizer.require(toFail: doubleTapRecognizer)
+    doubleTapRecognizer.require(toFail: tripleTapRecognizer)
 
-    leftSwipeRecognizer.require(toFail: shortPressRecognizer)
-    rightSwipeRecognizer.require(toFail: shortPressRecognizer)
+    // add a tap gesture for the answer bar for submitting in anki mode
+    let tapRecognizer = UITapGestureRecognizer(target: self, action: #selector(didTapAnswerBar))
+    answerField.addGestureRecognizer(tapRecognizer)
 
     resizeViewsForFontSize()
     viewDidLayoutSubviews()
@@ -728,6 +750,7 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
         submitButton.isHidden = false
       }
     }
+    updateSwipeConfiguration()
 
     // Change the submit button icon.
     let submitButtonImage = shown ? forwardArrowImage :
@@ -760,7 +783,7 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
     // Enable/disable the answer field, and set its first responder status.
     // This makes the keyboard appear or disappear immediately.  We need this animation to happen
     // here so it's in sync with the others.
-    answerField.isEnabled = !shown && !Settings.ankiMode
+    answerField.isInteractive = !shown && !Settings.ankiMode
     if updateFirstResponder {
       if !shown {
         answerField.becomeFirstResponder()
@@ -814,6 +837,8 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
       }
     }
 
+    updateSwipeConfiguration()
+
     // This makes sure taps are still processed and not ignored, even when the closing animation
     // after a button press was not completed
     if Settings.ankiMode, ankiModeCachedSubmit { submit() }
@@ -896,19 +921,12 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
     questionLabel.font = UIFont(name: fontName, size: questionLabelFontSize())
   }
 
-  @objc func didShortPressQuestionLabel(_: UITapGestureRecognizer) {
-    toggleFont()
-    if Settings.ankiMode {
-      if !isAnimatingSubjectDetailsView { submit() }
-      else { ankiModeCachedSubmit = true }
-    }
-  }
-
-  @objc func didSwipeQuestionLabel(_ sender: UISwipeGestureRecognizer) {
-    if sender.direction == .left {
-      showNextCustomFont()
-    } else if sender.direction == .right {
-      showPreviousCustomFont()
+  @objc func didTapQuestionView(_ sender: UITapGestureRecognizer) {
+    switch sender.numberOfTapsRequired {
+    case 1: toggleFont()
+    case 2: showNextCustomFont()
+    case 3: showPreviousCustomFont()
+    default: break
     }
   }
 
@@ -944,6 +962,7 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
   }
 
   func quickSettingsChanged() {
+    updateSwipeConfiguration()
     if subjectDetailsView.isHidden {
       updateViewForCurrentTask(updateFirstResponder: false)
     }
@@ -1006,7 +1025,7 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
       markAnswer(.AskAgainLater)
       return
     }
-    if !answerField.isEnabled, !Settings.ankiMode {
+    if !answerField.isInteractive, !Settings.ankiMode {
       if !subjectDetailsView.isHidden {
         subjectDetailsView.saveStudyMaterials()
       }
@@ -1020,7 +1039,7 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
   @objc func backspaceKeyPressed() {
     answerField.text = nil
     answerField.textColor = TKMStyle.Color.label
-    answerField.isEnabled = true
+    answerField.isInteractive = true
     answerField.becomeFirstResponder()
   }
 
@@ -1144,7 +1163,7 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
       UIView.animate(withDuration: animationDuration,
                      animations: {
                        self.answerField.textColor = .systemRed
-                       self.answerField.isEnabled = false
+                       self.answerField.isInteractive = false
                        self.revealAnswerButton.alpha = 1.0
                        self.submitButton.setImage(self.forwardArrowImage, for: .normal)
                      })
@@ -1170,6 +1189,13 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
                               updateFirstResponder: true)
   }
 
+  @objc func didTapAnswerBar(_: UITapGestureRecognizer) {
+    if Settings.ankiMode {
+      if !isAnimatingSubjectDetailsView { submit() }
+      else { ankiModeCachedSubmit = true }
+    }
+  }
+
   // MARK: - Ignoring incorrect answers
 
   @IBAction func addSynonymButtonPressed(_: Any) {
@@ -1183,7 +1209,7 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
 
     c.addAction(UIAlertAction(title: "My answer was correct",
                               style: .default,
-                              handler: { _ in self.markCorrect() }))
+                              handler: { _ in self.markOverrideCorrect() }))
     if Settings.ankiMode {
       c.addAction(UIAlertAction(title: "My answer was incorrect",
                                 style: .default,
@@ -1203,7 +1229,7 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
     present(c, animated: true, completion: nil)
   }
 
-  @objc func markCorrect() {
+  @objc func markOverrideCorrect() {
     markAnswer(.OverrideAnswerCorrect)
   }
 
@@ -1229,6 +1255,54 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
     super.canPerformAction(action, withSender: sender)
   }
 
+  // MARK: - Swipe Gesture Delegate
+
+  func containerDidSwipeRight(_: SwipeableContainer) {
+    // Handle correct answer
+    if !subjectDetailsView.isHidden {
+      // call the same function that is used by the synonyms menu to mark correct
+      markOverrideCorrect()
+    } else {
+      // use the marking function for outside the details view
+      markAnswer(.Correct)
+    }
+  }
+
+  func containerDidSwipeLeft(_: SwipeableContainer) {
+    if subjectDetailsView.isHidden {
+      _ = session.markAnswer(.Incorrect, isPracticeSession: isPracticeSession)
+    }
+    randomTask()
+  }
+
+  func containerDidSwipeDown(_: SwipeableContainer) {
+    // Skip question
+    if Settings.allowSkippingReviews {
+      markAnswer(.AskAgainLater)
+      return
+    }
+  }
+
+  func containerDidSwipeUp(_: SwipeableContainer) {
+    submit()
+  }
+
+  private func updateSwipeConfiguration() {
+    var config = SwipeableContainer.SwipeConfiguration()
+
+    guard Settings.ankiMode,
+          Settings.ankiModeEnableSwipeGestures else {
+      swipeContainer.updateSwipeConfiguration(config)
+      return
+    }
+
+    config.isRightEnabled = true
+    config.isLeftEnabled = true
+    config.isDownEnabled = Settings.allowSkippingReviews
+    config.isUpEnabled = subjectDetailsView.isHidden
+    swipeContainer.updateSwipeConfiguration(config)
+  }
+
   // MARK: - SubjectDelegate
 
   func didTapSubject(_ subject: TKMSubject) {
@@ -1252,7 +1326,7 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
                                           discoverabilityTitle: "Continue")
     var keyCommands: [UIKeyCommand] = []
 
-    if !answerField.isEnabled, subjectDetailsView.isHidden {
+    if !answerField.isInteractive, subjectDetailsView.isHidden {
       // Continue when a wrong answer has been entered but the subject details view is hidden.
       keyCommands.append(contentsOf: [UIKeyCommand(input: "\u{8}",
                                                    modifierFlags: [],
@@ -1276,11 +1350,11 @@ class ReviewViewController: UIViewController, UITextFieldDelegate, SubjectDelega
                                                    discoverabilityTitle: "Ask again later"),
                                       UIKeyCommand(input: "c",
                                                    modifierFlags: [.command],
-                                                   action: #selector(markCorrect),
+                                                   action: #selector(markOverrideCorrect),
                                                    discoverabilityTitle: "Mark correct"),
                                       UIKeyCommand(input: "c",
                                                    modifierFlags: [.control],
-                                                   action: #selector(markCorrect)),
+                                                   action: #selector(markOverrideCorrect)),
                                       UIKeyCommand(input: "i",
                                                    modifierFlags: [.command],
                                                    action: #selector(markIncorrect),

ios/Settings.swift

@@ -203,6 +203,8 @@ protocol SettingProtocol {
   @Setting(false, #keyPath(ankiMode)) static var ankiMode: Bool
   @Setting(false,
            #keyPath(ankiModeCombineReadingMeaning)) static var ankiModeCombineReadingMeaning: Bool
+  @Setting(false,
+           #keyPath(ankiModeEnableSwipeGestures)) static var ankiModeEnableSwipeGestures: Bool
   @Setting(true, #keyPath(showPreviousLevelGraph)) static var showPreviousLevelGraph: Bool
   @Setting(true, #keyPath(showKanaOnlyVocab)) static var showKanaOnlyVocab: Bool
 

ios/Style.swift

@@ -77,6 +77,14 @@ class TKMStyle: NSObject {
   static let explosionColor2 = UIColor(red: 230.0 / 255, green: 57.0 / 255, blue: 91.0 / 255,
                                        alpha: 1.0)
 
+  static let incorrectAnswerColor: UIColor = .init(red: 234.0 / 255, green: 51.0 / 255,
+                                                   blue: 61.0 / 255,
+                                                   alpha: 1.0) // also srsLevelDownColor
+  static let correctAnswerColor: UIColor = .init(red: 151.0 / 255, green: 202.0 / 255,
+                                                 blue: 62.0 / 255, alpha: 1.0)
+  static let srsLevelUpColor: UIColor = .init(red: 91.0 / 255, green: 168.0 / 255, blue: 51.0 / 255,
+                                              alpha: 1.0)
+
   static var radicalGradient: [CGColor] { [radicalColor1.cgColor, radicalColor2.cgColor] }
   static var kanjiGradient: [CGColor] { [kanjiColor1.cgColor, kanjiColor2.cgColor] }
   static var vocabularyGradient: [CGColor] { [vocabularyColor1.cgColor, vocabularyColor2.cgColor] }