Add hover effects to poll view

Closes #503

Tusker/Views/Poll/PollOptionView.swift

@@ -14,6 +14,7 @@ class PollOptionView: UIView {
     private static let minHeight: CGFloat = 35
     private static let cornerRadius = 0.1 * minHeight
     private static let unselectedBackgroundColor = UIColor(white: 0.5, alpha: 0.25)
+    private static let hoveredBackgroundColor = UIColor(white: 0.35, alpha: 0.25)
     
     private(set) var label: EmojiLabel!
     @Lazy private var checkbox: PollOptionCheckboxView = PollOptionCheckboxView().configure {
@@ -33,6 +34,12 @@ class PollOptionView: UIView {
     private var labelLeadingToSelfConstraint: NSLayoutConstraint!
     private var fillViewWidthConstraint: NSLayoutConstraint?
     
+    var hovered: Bool = false {
+        didSet {
+            backgroundColor = hovered ? PollOptionView.hoveredBackgroundColor : PollOptionView.unselectedBackgroundColor
+        }
+    }
+    
     init() {
         super.init(frame: .zero)
         

Tusker/Views/Poll/PollOptionsView.swift

@@ -24,9 +24,10 @@ class PollOptionsView: UIControl {
     private var poll: Poll!
     private var animator: UIViewPropertyAnimator!
     private var currentSelectedOptionIndex: Int?
+    private var currentHoveredOptionIndex: Int?
     
-    private let animationDuration: TimeInterval = 0.1
+    static let animationDuration: TimeInterval = 0.1
-    private let scaledTransform = CGAffineTransform(scaleX: 0.95, y: 0.95)
+    static let scaledTransform = CGAffineTransform(scaleX: 0.95, y: 0.95)
     
     #if !os(visionOS)
     private let generator = UISelectionFeedbackGenerator()
@@ -59,6 +60,8 @@ class PollOptionsView: UIControl {
             stack.topAnchor.constraint(equalTo: topAnchor),
             stack.bottomAnchor.constraint(equalTo: bottomAnchor),
         ])
+        
+        addGestureRecognizer(UIHoverGestureRecognizer(target: self, action: #selector(hoverRecognized)))
     }
     
     required init?(coder: NSCoder) {
@@ -121,6 +124,20 @@ class PollOptionsView: UIControl {
         }
     }
     
+    private func optionView(at point: CGPoint) -> (PollOptionView, Int)? {
+        for (index, view) in options.enumerated() {
+            // don't use view.frame because it changes when a transform is applied
+            var frame = CGRect(x: 0, y: view.center.y - view.bounds.height / 2, width: view.bounds.width, height: view.bounds.height)
+            if index != options.count - 1 {
+                frame = frame.inset(by: UIEdgeInsets(top: 0, left: 0, bottom: -stack.spacing, right: 0))
+            }
+            if frame.contains(point) {
+                return (view, index)
+            }
+        }
+        return nil
+    }
+    
     // MARK: - UIControl
     
     override func beginTracking(_ touch: UITouch, with event: UIEvent?) -> Bool {
@@ -132,8 +149,12 @@ class PollOptionsView: UIControl {
             if view.point(inside: touch.location(in: view), with: event) {
                 currentSelectedOptionIndex = index
                 
-                animator = UIViewPropertyAnimator(duration: animationDuration, curve: .easeInOut) {
+                if animator?.isRunning == true {
-                    view.transform = self.scaledTransform
+                    animator.stopAnimation(true)
+                }
+                animator = UIViewPropertyAnimator(duration: Self.animationDuration, curve: .easeInOut) {
+                    view.transform = Self.scaledTransform
+                    view.hovered = true
                 }
                 animator.startAnimation()
                 
@@ -151,27 +172,21 @@ class PollOptionsView: UIControl {
     
     override func continueTracking(_ touch: UITouch, with event: UIEvent?) -> Bool {
         let location = touch.location(in: self)
-        var newIndex: Int? = nil
+        let newIndex = optionView(at: location)?.1
-        for (index, view) in options.enumerated() {
-            // don't use view.frame because it changes when a transform is applied
-            var frame = CGRect(x: 0, y: view.center.y - view.bounds.height / 2, width: view.bounds.width, height: view.bounds.height)
-            if index != options.count - 1 {
-                frame = frame.inset(by: UIEdgeInsets(top: 0, left: 0, bottom: -stack.spacing, right: 0))
-            }
-            if frame.contains(location) {
-                newIndex = index
-                break
-            }
-        }
         
         if newIndex != currentSelectedOptionIndex {
             currentSelectedOptionIndex = newIndex
             
-            UIView.animate(withDuration: animationDuration, delay: 0, options: .curveEaseInOut) {
+            if animator.isRunning {
+                animator.stopAnimation(true)
+            }
+            animator = UIViewPropertyAnimator(duration: Self.animationDuration, curve: .easeInOut) {
                 for (index, view) in self.options.enumerated() {
-                    view.transform = index == newIndex ? self.scaledTransform : .identity
+                    view.transform = index == newIndex ? Self.scaledTransform : .identity
+                    view.hovered = index == newIndex
                 }
             }
+            animator.startAnimation()
             
             #if !os(visionOS)
             if newIndex != nil {
@@ -190,14 +205,15 @@ class PollOptionsView: UIControl {
         func selectOption() {
             guard let index = currentSelectedOptionIndex else { return }
             let option = options[index]
-            animator = UIViewPropertyAnimator(duration: animationDuration, curve: .easeInOut) {
+            animator = UIViewPropertyAnimator(duration: Self.animationDuration, curve: .easeInOut) {
                 option.transform = .identity
+                option.hovered = false
                 self.selectOption(option)
             }
             animator.startAnimation()
         }
         
-        if animator.isRunning {
+        if animator?.isRunning == true {
             animator.addCompletion { (_) in
                 selectOption()
             }
@@ -208,12 +224,52 @@ class PollOptionsView: UIControl {
     
     override func cancelTracking(with event: UIEvent?) {
         super.cancelTracking(with: event)
-        UIView.animate(withDuration: animationDuration, delay: 0, options: .curveEaseInOut) {
+        if animator?.isRunning == true {
+            animator.stopAnimation(true)
+        }
+        animator = UIViewPropertyAnimator(duration: Self.animationDuration, curve: .easeInOut) {
             for view in self.options {
                 view.transform = .identity
+                view.hovered = false
             }
         }
-
+        animator.startAnimation()
+    }
+    
+    @objc private func hoverRecognized(_ recognizer: UIHoverGestureRecognizer) {
+        guard let (option, index) = optionView(at: recognizer.location(in: self)) else {
+            return
+        }
+        switch recognizer.state {
+        case .began, .changed:
+            if index != currentHoveredOptionIndex {
+                let oldIndex = currentHoveredOptionIndex
+                currentHoveredOptionIndex = index
+                if animator?.isRunning == true {
+                    animator.stopAnimation(true)
+                }
+                animator = UIViewPropertyAnimator(duration: Self.animationDuration, curve: .easeInOut) {
+                    option.hovered = true
+                    if let oldIndex {
+                        self.options[oldIndex].hovered = false
+                    }
+                }
+                animator.startAnimation()
+            }
+        case .ended, .cancelled:
+            if let currentHoveredOptionIndex {
+                self.currentHoveredOptionIndex = nil
+                if animator?.isRunning == true {
+                    animator.stopAnimation(true)
+                }
+                animator = UIViewPropertyAnimator(duration: Self.animationDuration, curve: .easeInOut) {
+                    self.options[currentHoveredOptionIndex].hovered = false
+                }
+                animator.startAnimation()
+            }
+        default:
+            break
+        }
     }
 
 }

Tusker/Views/Poll/StatusPollView.swift

@@ -65,6 +65,7 @@ class StatusPollView: UIView, StatusContentView {
         addSubview(infoLabel)
         
         voteButton = UIButton(configuration: .plain())
+        voteButton.isPointerInteractionEnabled = true
         voteButton.translatesAutoresizingMaskIntoConstraints = false
         voteButton.addTarget(self, action: #selector(votePressed), for: .touchUpInside)
         voteButton.setContentCompressionResistancePriority(.defaultHigh, for: .horizontal)