Mark items as read

Reader/Screens/Home/HomeCollectionViewCell.swift

@@ -11,10 +11,11 @@ class HomeCollectionViewCell: UICollectionViewListCell {
     
     override func updateConfiguration(using state: UICellConfigurationState) {
         var backgroundConfig = UIBackgroundConfiguration.listGroupedCell().updated(for: state)
-        if !state.isHighlighted && !state.isSelected {
+        if state.isHighlighted || state.isSelected {
+            backgroundConfig.backgroundColor = .appCellHighlightBackground
+        } else {
             backgroundConfig.backgroundColor = .appBackground
         }
-        // todo: this breaks the deselection animation
         self.backgroundConfiguration = backgroundConfig
     }
     

Reader/Screens/Items/ItemCollectionViewCell.swift

@@ -8,11 +8,20 @@
 import UIKit
 import SwiftSoup
 
+protocol ItemCollectionViewCellDelegate: AnyObject {
+    func itemCellSelected(item: Item)
+}
+
 class ItemCollectionViewCell: UICollectionViewListCell {
     
+    weak var delegate: ItemCollectionViewCellDelegate?
+    
     private let titleLabel = UILabel()
     private let feedTitleLabel = UILabel()
     private let contentLabel = UILabel()
+    private var shouldHighlight = true
+    
+    private var item: Item!
     
     override init(frame: CGRect) {
         super.init(frame: frame)
@@ -24,10 +33,8 @@ class ItemCollectionViewCell: UICollectionViewListCell {
         titleLabel.numberOfLines = 0
         
         feedTitleLabel.font = UIFont(descriptor: .preferredFontDescriptor(withTextStyle: .subheadline), size: 0)
-        feedTitleLabel.textColor = .tintColor
         
         contentLabel.font = UIFont(descriptor: .preferredFontDescriptor(withTextStyle: .body).withDesign(.serif)!, size: 0)
-        contentLabel.textColor = .appContentPreviewLabel
         contentLabel.numberOfLines = 0
         
         let stack = UIStackView(arrangedSubviews: [
@@ -46,6 +53,14 @@ class ItemCollectionViewCell: UICollectionViewListCell {
             stack.bottomAnchor.constraint(equalTo: bottomAnchor, constant: -8),
             separatorLayoutGuide.leadingAnchor.constraint(equalTo: stack.leadingAnchor),
         ])
+        
+        let doubleTap = DoubleTapRecognizer(target: self, action: #selector(cellDoubleTapped))
+        doubleTap.onTouchesBegan = highlightCell
+        addGestureRecognizer(doubleTap)
+        
+        let singleTap = UITapGestureRecognizer(target: self, action: #selector(cellSingleTapped))
+        singleTap.require(toFail: doubleTap)
+        addGestureRecognizer(singleTap)
     }
     
     required init?(coder: NSCoder) {
@@ -53,6 +68,8 @@ class ItemCollectionViewCell: UICollectionViewListCell {
     }
     
     func updateUI(item: Item) {
+        self.item = item
+        
         titleLabel.text = item.title
         feedTitleLabel.text = item.feed!.title ?? item.feed!.url?.host
         if let content = item.content {
@@ -62,6 +79,66 @@ class ItemCollectionViewCell: UICollectionViewListCell {
             contentLabel.text = ""
         }
         contentLabel.isHidden = contentLabel.text?.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty ?? true
+        
+        setColors()
+    }
+    
+    private func setColors() {
+        if item.read {
+            titleLabel.textColor = .secondaryLabel
+            feedTitleLabel.textColor = .secondaryLabel
+            contentLabel.textColor = .secondaryLabel
+        } else {
+            titleLabel.textColor = .label
+            feedTitleLabel.textColor = .tintColor
+            contentLabel.textColor = .appContentPreviewLabel
+        }
+    }
+    
+    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
+        highlightCell()
+    }
+    
+    @objc private func highlightCell() {
+        guard shouldHighlight else { return }
+        shouldHighlight = false
+        UIView.animateKeyframes(withDuration: 0.4, delay: 0, options: .allowUserInteraction) {
+            UIView.addKeyframe(withRelativeStartTime: 0, relativeDuration: 0.5) {
+                self.backgroundColor = .appCellHighlightBackground
+            }
+            UIView.addKeyframe(withRelativeStartTime: 0.5, relativeDuration: 0.5) {
+                self.backgroundColor = nil
+            }
+        }
+    }
+    
+    @objc private func cellDoubleTapped() {
+        self.item.read = !self.item.read
+        // i don't know why .transition works but .animate doesn't
+        UIView.transition(with: self, duration: 0.2, options: .transitionCrossDissolve) {
+            self.setColors()
+        }
+        shouldHighlight = true
+    }
+    
+    @objc private func cellSingleTapped() {
+        delegate?.itemCellSelected(item: item)
+        shouldHighlight = true
     }
 
 }
+
+private class DoubleTapRecognizer: UITapGestureRecognizer {
+    var onTouchesBegan: (() -> Void)!
+    
+    override init(target: Any?, action: Selector?) {
+        super.init(target: target, action: action)
+        numberOfTapsRequired = 2
+        delaysTouchesBegan = true
+    }
+    
+    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
+        super.touchesBegan(touches, with: event)
+        onTouchesBegan()
+    }
+}

Reader/Screens/Items/ItemsViewController.swift

@@ -35,7 +35,6 @@ class ItemsViewController: UIViewController {
         configuration.backgroundColor = .appBackground
         let layout = UICollectionViewCompositionalLayout.list(using: configuration)
         collectionView = UICollectionView(frame: view.bounds, collectionViewLayout: layout)
-        collectionView.delegate = self
         collectionView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
         collectionView.register(ItemCollectionViewCell.self, forCellWithReuseIdentifier: "itemCell")
         view.addSubview(collectionView)
@@ -53,8 +52,9 @@ class ItemsViewController: UIViewController {
     }
     
     private func createDataSource() -> UICollectionViewDiffableDataSource<Section, Item> {
-        let itemCell = UICollectionView.CellRegistration<ItemCollectionViewCell, Item> { cell, indexPath, item in
+        let itemCell = UICollectionView.CellRegistration<ItemCollectionViewCell, Item> { [unowned self] cell, indexPath, item in
             cell.updateUI(item: item)
+            cell.delegate = self
         }
         let dataSource = UICollectionViewDiffableDataSource<Section, Item>(collectionView: collectionView) { collectionView, indexPath, item in
             return collectionView.dequeueConfiguredReusableCell(using: itemCell, for: indexPath, item: item)
@@ -80,12 +80,8 @@ extension ItemsViewController: NSFetchedResultsControllerDelegate {
     }
 }
 
-extension ItemsViewController: UICollectionViewDelegate {
-    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
-        guard let item = dataSource.itemIdentifier(for: indexPath) else {
-            return
-        }
-        let vc = ReadViewController(item: item, fervorController: fervorController)
-        show(vc, sender: nil)
+extension ItemsViewController: ItemCollectionViewCellDelegate {
+    func itemCellSelected(item: Item) {
+        show(ReadViewController(item: item, fervorController: fervorController), sender: nil)
     }
 }

Reader/UIColor+App.swift

@@ -20,6 +20,17 @@ extension UIColor {
         }
     }
     
+    static let appCellHighlightBackground = UIColor { traitCollection in
+        switch traitCollection.userInterfaceStyle {
+        case .dark:
+            return UIColor(white: 0.15, alpha: 1)
+        case .unspecified, .light:
+            fallthrough
+        @unknown default:
+            return UIColor(white: 0.9, alpha: 1)
+        }
+    }
+    
     static let appContentPreviewLabel = UIColor { traitCollection in
         switch traitCollection.userInterfaceStyle {
         case .dark: