Replaces BrowseCollectionViewCell with AppCardCollectionViewCell

* Handles dynamic screenshot sizes
* Allows swiping through screenshots
* Supports iPhone + iPad screenshots

AltStore/App Detail/Screenshots/AppScreenshotCollectionViewCell.swift

@@ -10,6 +10,20 @@ import UIKit
 
 import AltStoreCore
 
+extension AppScreenshotCollectionViewCell
+{
+    private class ImageView: UIImageView
+    {
+        override func layoutSubviews()
+        {
+            super.layoutSubviews()
+            
+            // Explicitly layout cell to ensure rounded corners are accurate.
+            self.superview?.superview?.setNeedsLayout()
+        }
+    }
+}
+
 class AppScreenshotCollectionViewCell: UICollectionViewCell
 {
     let imageView: UIImageView
@@ -31,21 +45,21 @@ class AppScreenshotCollectionViewCell: UICollectionViewCell
     
     override init(frame: CGRect)
     {
-        self.imageView = UIImageView(frame: .zero)
+        self.imageView = ImageView(frame: .zero)
         self.imageView.clipsToBounds = true
         self.imageView.layer.cornerCurve = .continuous
         self.imageView.layer.borderColor = UIColor.tertiaryLabel.cgColor
-                
+        
         super.init(frame: frame)
         
         self.imageView.translatesAutoresizingMaskIntoConstraints = false
         self.contentView.addSubview(self.imageView)
         
         let widthConstraint = self.imageView.widthAnchor.constraint(equalTo: self.contentView.widthAnchor)
-        widthConstraint.priority = UILayoutPriority(999)
+        widthConstraint.priority = .defaultHigh
         
         let heightConstraint = self.imageView.heightAnchor.constraint(equalTo: self.contentView.heightAnchor)
-        heightConstraint.priority = UILayoutPriority(999)
+        heightConstraint.priority = .defaultHigh
         
         NSLayoutConstraint.activate([
             widthConstraint,
@@ -64,7 +78,7 @@ class AppScreenshotCollectionViewCell: UICollectionViewCell
         fatalError("init(coder:) has not been implemented")
     }
     
-    override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?) 
+    override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?)
     {
         super.traitCollectionDidChange(previousTraitCollection)
         
@@ -75,11 +89,6 @@ class AppScreenshotCollectionViewCell: UICollectionViewCell
     {
         super.layoutSubviews()
         
-        guard self.imageView.bounds.width != 0 else {
-            self.setNeedsLayout()
-            return
-        }
-        
         if self.isRounded
         {
             let cornerRadius = self.imageView.bounds.width / 9.0 // Based on iPhone 15

AltStore/Base.lproj/Main.storyboard

@@ -50,7 +50,7 @@
         <!--Browse-->
         <scene sceneID="rXq-UR-qQp">
             <objects>
-                <collectionViewController id="e3L-BF-iXp" customClass="BrowseViewController" customModule="AltStore" customModuleProvider="target" sceneMemberID="viewController">
+                <collectionViewController storyboardIdentifier="browseViewController" id="e3L-BF-iXp" customClass="BrowseViewController" customModule="AltStore" customModuleProvider="target" sceneMemberID="viewController">
                     <collectionView key="view" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="scaleToFill" dataMode="prototypes" id="CaT-1q-qnx">
                         <rect key="frame" x="0.0" y="0.0" width="375" height="667"/>
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>

AltStore/Browse/BrowseCollectionViewCell.swift

@@ -1,96 +0,0 @@
-//
-//  BrowseCollectionViewCell.swift
-//  AltStore
-//
-//  Created by Riley Testut on 7/15/19.
-//  Copyright © 2019 Riley Testut. All rights reserved.
-//
-
-import UIKit
-
-import Roxas
-
-import Nuke
-
-@objc class BrowseCollectionViewCell: UICollectionViewCell
-{
-    var imageURLs: [URL] = [] {
-        didSet {
-            self.dataSource.items = self.imageURLs as [NSURL]
-        }
-    }
-    private lazy var dataSource = self.makeDataSource()
-    
-    @IBOutlet var bannerView: AppBannerView!
-    @IBOutlet var subtitleLabel: UILabel!
-    
-    @IBOutlet private(set) var screenshotsCollectionView: UICollectionView!
-    
-    override func awakeFromNib()
-    {
-        super.awakeFromNib()
-        
-        self.contentView.preservesSuperviewLayoutMargins = true
-        
-        // Must be registered programmatically, not in BrowseCollectionViewCell.xib, or else it'll throw an exception 🤷‍♂️.
-        self.screenshotsCollectionView.register(ScreenshotCollectionViewCell.self, forCellWithReuseIdentifier: RSTCellContentGenericCellIdentifier)
-        
-        self.screenshotsCollectionView.delegate = self
-        self.screenshotsCollectionView.dataSource = self.dataSource
-        self.screenshotsCollectionView.prefetchDataSource = self.dataSource
-    }
-}
-
-private extension BrowseCollectionViewCell
-{
-    func makeDataSource() -> RSTArrayCollectionViewPrefetchingDataSource<NSURL, UIImage>
-    {
-        let dataSource = RSTArrayCollectionViewPrefetchingDataSource<NSURL, UIImage>(items: [])
-        dataSource.cellConfigurationHandler = { (cell, screenshot, indexPath) in
-            let cell = cell as! ScreenshotCollectionViewCell
-            cell.imageView.image = nil
-            cell.imageView.isIndicatingActivity = true
-        }
-        dataSource.prefetchHandler = { (imageURL, indexPath, completionHandler) in
-            return RSTAsyncBlockOperation() { (operation) in
-                let request = ImageRequest(url: imageURL as URL)
-                ImagePipeline.shared.loadImage(with: request, progress: nil) { result in
-                    guard !operation.isCancelled else { return operation.finish() }
-                    
-                    switch result
-                    {
-                    case .success(let response): completionHandler(response.image, nil)
-                    case .failure(let error): completionHandler(nil, error)
-                    }
-                }
-            }
-        }
-        dataSource.prefetchCompletionHandler = { (cell, image, indexPath, error) in
-            let cell = cell as! ScreenshotCollectionViewCell
-            cell.imageView.isIndicatingActivity = false
-            cell.imageView.image = image
-            
-            if let error = error
-            {
-                print("Error loading image:", error)
-            }
-        }
-        
-        return dataSource
-    }
-}
-
-extension BrowseCollectionViewCell: UICollectionViewDelegateFlowLayout
-{
-    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize
-    {
-        // Assuming 9.0 / 16.0 ratio for now.
-        let aspectRatio: CGFloat = 9.0 / 16.0
-
-        let itemHeight = collectionView.bounds.height
-        let itemWidth = itemHeight * aspectRatio
-
-        let size = CGSize(width: itemWidth.rounded(.down), height: itemHeight.rounded(.down))
-        return size
-    }
-}

AltStore/Browse/BrowseCollectionViewCell.xib

@@ -1,64 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="15400" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES">
-    <device id="retina6_1" orientation="portrait" appearance="light"/>
-    <dependencies>
-        <deployment identifier="iOS"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="15404"/>
-        <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
-    </dependencies>
-    <objects>
-        <placeholder placeholderIdentifier="IBFilesOwner" id="-1" userLabel="File's Owner"/>
-        <placeholder placeholderIdentifier="IBFirstResponder" id="-2" customClass="UIResponder"/>
-        <collectionViewCell opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" insetsLayoutMarginsFromSafeArea="NO" reuseIdentifier="Cell" id="ln4-pC-7KY" customClass="BrowseCollectionViewCell" customModule="AltStore" customModuleProvider="target">
-            <rect key="frame" x="0.0" y="0.0" width="375" height="369"/>
-            <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
-            <view key="contentView" opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" insetsLayoutMarginsFromSafeArea="NO">
-                <rect key="frame" x="0.0" y="0.0" width="375" height="369"/>
-                <autoresizingMask key="autoresizingMask"/>
-                <subviews>
-                    <stackView verifyAmbiguity="off" opaque="NO" contentMode="scaleToFill" ambiguous="YES" axis="vertical" spacing="15" translatesAutoresizingMaskIntoConstraints="NO" id="5gU-g3-Fsy">
-                        <rect key="frame" x="16" y="0.0" width="343" height="369"/>
-                        <subviews>
-                            <view contentMode="scaleToFill" translatesAutoresizingMaskIntoConstraints="NO" id="ziA-mP-AY2" customClass="AppBannerView" customModule="AltStore" customModuleProvider="target">
-                                <rect key="frame" x="0.0" y="0.0" width="343" height="88"/>
-                                <color key="backgroundColor" systemColor="systemBackgroundColor" cocoaTouchSystemColor="whiteColor"/>
-                                <constraints>
-                                    <constraint firstAttribute="height" constant="88" id="z3D-cI-jhp"/>
-                                </constraints>
-                            </view>
-                            <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="Classic Nintendo games in your pocket." textAlignment="center" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" minimumScaleFactor="0.5" translatesAutoresizingMaskIntoConstraints="NO" id="Imx-Le-bcy">
-                                <rect key="frame" x="0.0" y="103" width="343" height="17"/>
-                                <fontDescription key="fontDescription" type="system" pointSize="14"/>
-                                <nil key="textColor"/>
-                                <nil key="highlightedColor"/>
-                            </label>
-                            <collectionView clipsSubviews="YES" multipleTouchEnabled="YES" userInteractionEnabled="NO" contentMode="scaleToFill" scrollEnabled="NO" contentInsetAdjustmentBehavior="never" dataMode="none" translatesAutoresizingMaskIntoConstraints="NO" id="RFs-qp-Ca4">
-                                <rect key="frame" x="0.0" y="135" width="343" height="234"/>
-                                <color key="backgroundColor" white="0.0" alpha="0.0" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
-                                <collectionViewFlowLayout key="collectionViewLayout" minimumLineSpacing="0.0" minimumInteritemSpacing="15" id="jH9-Jo-IHA">
-                                    <size key="itemSize" width="120" height="213"/>
-                                    <size key="headerReferenceSize" width="0.0" height="0.0"/>
-                                    <size key="footerReferenceSize" width="0.0" height="0.0"/>
-                                    <inset key="sectionInset" minX="8" minY="0.0" maxX="8" maxY="0.0"/>
-                                </collectionViewFlowLayout>
-                                <cells/>
-                            </collectionView>
-                        </subviews>
-                    </stackView>
-                </subviews>
-            </view>
-            <constraints>
-                <constraint firstItem="5gU-g3-Fsy" firstAttribute="top" secondItem="ln4-pC-7KY" secondAttribute="top" id="DnT-vq-BOc"/>
-                <constraint firstItem="5gU-g3-Fsy" firstAttribute="leading" secondItem="ln4-pC-7KY" secondAttribute="leadingMargin" id="YPy-xL-iUn"/>
-                <constraint firstAttribute="bottom" secondItem="5gU-g3-Fsy" secondAttribute="bottom" id="gRu-Hz-CNL"/>
-                <constraint firstAttribute="trailingMargin" secondItem="5gU-g3-Fsy" secondAttribute="trailing" id="vf4-ql-4Vq"/>
-            </constraints>
-            <connections>
-                <outlet property="bannerView" destination="ziA-mP-AY2" id="yxo-ar-Cha"/>
-                <outlet property="screenshotsCollectionView" destination="RFs-qp-Ca4" id="xfi-AN-l17"/>
-                <outlet property="subtitleLabel" destination="Imx-Le-bcy" id="JVW-ZZ-51O"/>
-            </connections>
-            <point key="canvasLocation" x="136.95652173913044" y="152.67857142857142"/>
-        </collectionViewCell>
-    </objects>
-</document>

AltStore/Browse/BrowseViewController.swift

@@ -21,7 +21,7 @@ class BrowseViewController: UICollectionViewController, PeekPopPreviewing
     private lazy var dataSource = self.makeDataSource()
     private lazy var placeholderView = RSTPlaceholderView(frame: .zero)
     
-    private let prototypeCell = BrowseCollectionViewCell.instantiate(with: BrowseCollectionViewCell.nib!)!
+    private let prototypeCell = AppCardCollectionViewCell(frame: .zero)
     
     private var loadingState: LoadingState = .loading {
         didSet {
@@ -56,7 +56,7 @@ class BrowseViewController: UICollectionViewController, PeekPopPreviewing
         
         self.prototypeCell.contentView.translatesAutoresizingMaskIntoConstraints = false
         
-        self.collectionView.register(BrowseCollectionViewCell.nib, forCellWithReuseIdentifier: RSTCellContentGenericCellIdentifier)
+        self.collectionView.register(AppCardCollectionViewCell.self, forCellWithReuseIdentifier: RSTCellContentGenericCellIdentifier)
         
         self.collectionView.dataSource = self.dataSource
         self.collectionView.prefetchDataSource = self.dataSource
@@ -123,14 +123,11 @@ private extension BrowseViewController
         let context = self.source?.managedObjectContext ?? DatabaseManager.shared.viewContext
         let dataSource = RSTFetchedResultsCollectionViewPrefetchingDataSource<StoreApp, UIImage>(fetchRequest: fetchRequest, managedObjectContext: context)
         dataSource.cellConfigurationHandler = { (cell, app, indexPath) in
-            let cell = cell as! BrowseCollectionViewCell
+            let cell = cell as! AppCardCollectionViewCell
             cell.layoutMargins.left = self.view.layoutMargins.left
             cell.layoutMargins.right = self.view.layoutMargins.right
             
-            cell.subtitleLabel.text = app.subtitle
-            cell.imageURLs = Array(app.screenshotURLs.prefix(2))
-            
-            cell.bannerView.configure(for: app)
+            cell.configure(for: app)
             
             cell.bannerView.iconImageView.image = nil
             cell.bannerView.iconImageView.isIndicatingActivity = true
@@ -190,7 +187,7 @@ private extension BrowseViewController
             }
         }
         dataSource.prefetchCompletionHandler = { (cell, image, indexPath, error) in
-            let cell = cell as! BrowseCollectionViewCell
+            let cell = cell as! AppCardCollectionViewCell
             cell.bannerView.iconImageView.isIndicatingActivity = false
             cell.bannerView.iconImageView.image = image
             
@@ -369,21 +366,18 @@ extension BrowseViewController: UICollectionViewDelegateFlowLayout
     func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize
     {
         let item = self.dataSource.item(at: indexPath)
+        let itemID = item.globallyUniqueID ?? item.bundleIdentifier
 
-        if let previousSize = self.cachedItemSizes[item.bundleIdentifier]
+        if let previousSize = self.cachedItemSizes[itemID]
         {
             return previousSize
         }
-
-        let maxVisibleScreenshots = 2 as CGFloat
-        let aspectRatio: CGFloat = 16.0 / 9.0
         
-        let layout = self.prototypeCell.screenshotsCollectionView.collectionViewLayout as! UICollectionViewFlowLayout
-        let padding = (layout.minimumInteritemSpacing * (maxVisibleScreenshots - 1)) + layout.sectionInset.left + layout.sectionInset.right
-
         self.dataSource.cellConfigurationHandler(self.prototypeCell, item, indexPath)
+        
+        let insets = (self.view.layoutMargins.left + self.view.layoutMargins.right)
 
-        let widthConstraint = self.prototypeCell.contentView.widthAnchor.constraint(equalToConstant: collectionView.bounds.width)
+        let widthConstraint = self.prototypeCell.contentView.widthAnchor.constraint(equalToConstant: collectionView.bounds.width - insets)
         widthConstraint.isActive = true
         defer { widthConstraint.isActive = false }
 
@@ -391,17 +385,8 @@ extension BrowseViewController: UICollectionViewDelegateFlowLayout
         self.prototypeCell.frame.size.width = widthConstraint.constant
         self.prototypeCell.layoutIfNeeded()
         
-        let collectionViewWidth = self.prototypeCell.screenshotsCollectionView.bounds.width
-        let screenshotWidth = ((collectionViewWidth - padding) / maxVisibleScreenshots).rounded(.down)
-        let screenshotHeight = screenshotWidth * aspectRatio
-
-        let heightConstraint = self.prototypeCell.screenshotsCollectionView.heightAnchor.constraint(equalToConstant: screenshotHeight)
-        heightConstraint.priority = .defaultHigh // Prevent temporary unsatisfiable constraints error.
-        heightConstraint.isActive = true
-        defer { heightConstraint.isActive = false }
-
         let itemSize = self.prototypeCell.contentView.systemLayoutSizeFitting(UIView.layoutFittingCompressedSize)
-        self.cachedItemSizes[item.bundleIdentifier] = itemSize
+        self.cachedItemSizes[itemID] = itemSize
         return itemSize
     }
     
@@ -438,3 +423,16 @@ extension BrowseViewController: UIViewControllerPreviewingDelegate
         self.navigationController?.pushViewController(viewControllerToCommit, animated: true)
     }
 }
+
+@available(iOS 17, *)
+#Preview(traits: .portrait) {
+    DatabaseManager.shared.startForPreview()
+   
+    let storyboard = UIStoryboard(name: "Main", bundle: .main)
+    let browseViewController = storyboard.instantiateViewController(identifier: "browseViewController") { coder in
+        BrowseViewController(source: nil, coder: coder)
+    }
+    
+    let navigationController = UINavigationController(rootViewController: browseViewController)
+    return navigationController
+}

AltStore/Components/AppCardCollectionViewCell.swift

@@ -0,0 +1,276 @@
+//
+//  AppCardCollectionViewCell.swift
+//  AltStore
+//
+//  Created by Riley Testut on 10/13/23.
+//  Copyright © 2023 Riley Testut. All rights reserved.
+//
+
+import UIKit
+
+import AltStoreCore
+import Roxas
+
+import Nuke
+
+private let minimumItemSpacing = 8.0
+
+class AppCardCollectionViewCell: UICollectionViewCell
+{
+    let bannerView: AppBannerView
+    
+    private let screenshotsCollectionView: UICollectionView
+    private let stackView: UIStackView
+    
+    private lazy var dataSource = self.makeDataSource()
+    
+    private var screenshots: [AppScreenshot] = [] {
+        didSet {
+            self.dataSource.items = self.screenshots
+        }
+    }
+    
+    override init(frame: CGRect)
+    {
+        self.bannerView = AppBannerView(frame: .zero)
+        
+        self.screenshotsCollectionView = UICollectionView(frame: .zero, collectionViewLayout: UICollectionViewFlowLayout())
+        self.screenshotsCollectionView.backgroundColor = nil
+        self.screenshotsCollectionView.alwaysBounceVertical = false
+        self.screenshotsCollectionView.alwaysBounceHorizontal = true
+        self.screenshotsCollectionView.showsHorizontalScrollIndicator = false
+        self.screenshotsCollectionView.showsVerticalScrollIndicator = false
+        
+        self.stackView = UIStackView(arrangedSubviews: [self.bannerView, self.screenshotsCollectionView])
+        self.stackView.translatesAutoresizingMaskIntoConstraints = false
+        self.stackView.spacing = 0
+        self.stackView.axis = .vertical
+        self.stackView.alignment = .fill
+        self.stackView.distribution = .equalSpacing
+        
+        super.init(frame: frame)
+        
+        self.contentView.clipsToBounds = true
+        self.contentView.layer.cornerCurve = .continuous
+        
+        self.contentView.addSubview(self.bannerView.backgroundEffectView, pinningEdgesWith: .zero)
+        self.contentView.addSubview(self.stackView, pinningEdgesWith: .zero)
+        
+        self.screenshotsCollectionView.collectionViewLayout = self.makeLayout()
+        self.screenshotsCollectionView.dataSource = self.dataSource
+        self.screenshotsCollectionView.prefetchDataSource = self.dataSource
+        
+        // Adding screenshotsCollectionView's gesture recognizers to self.contentView breaks paging,
+        // so instead we intercept taps and pass them onto delegate.
+        let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(AppCardCollectionViewCell.handleTapGesture(_:)))
+        tapGestureRecognizer.cancelsTouchesInView = false
+        tapGestureRecognizer.delaysTouchesBegan = false
+        tapGestureRecognizer.delaysTouchesEnded = false
+        self.screenshotsCollectionView.addGestureRecognizer(tapGestureRecognizer)
+        
+        self.screenshotsCollectionView.register(AppScreenshotCollectionViewCell.self, forCellWithReuseIdentifier: RSTCellContentGenericCellIdentifier)
+        
+        let inset = 14.0 //TODO: Assign from bannerView's layoutMargins
+        self.stackView.isLayoutMarginsRelativeArrangement = true
+        self.stackView.layoutMargins.bottom = inset
+        
+        self.contentView.preservesSuperviewLayoutMargins = true
+        self.screenshotsCollectionView.directionalLayoutMargins = NSDirectionalEdgeInsets(top: 0, leading: inset, bottom: 0, trailing: inset)
+        
+        // Aspect ratio constraint to fit exactly 3 modern portrait iPhone screenshots side-by-side (with spacing).
+        let multiplier = (AppScreenshot.defaultAspectRatio.width * 3) / AppScreenshot.defaultAspectRatio.height
+        let spacing = (inset * 2) + (minimumItemSpacing * 2)
+        let aspectRatioConstraint = self.screenshotsCollectionView.widthAnchor.constraint(equalTo: self.screenshotsCollectionView.heightAnchor, multiplier: multiplier, constant: spacing)
+        
+        NSLayoutConstraint.activate([
+            aspectRatioConstraint,
+            self.bannerView.heightAnchor.constraint(equalToConstant: 88)
+        ])
+    }
+    
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+    
+    override func layoutSubviews()
+    {
+        super.layoutSubviews()
+        
+        self.contentView.layer.cornerRadius = self.bannerView.layer.cornerRadius
+    }
+}
+
+private extension AppCardCollectionViewCell
+{
+    func makeLayout() -> UICollectionViewCompositionalLayout
+    {
+        let layoutConfig = UICollectionViewCompositionalLayoutConfiguration()
+        layoutConfig.contentInsetsReference = .layoutMargins
+        
+        let layout = UICollectionViewCompositionalLayout(sectionProvider: { [weak self] (sectionIndex, layoutEnvironment) -> NSCollectionLayoutSection? in
+            guard let self else { return nil }
+            
+            var contentWidth = 0.0
+            var numberOfVisibleScreenshots = 0
+            
+            for screenshot in self.screenshots
+            {
+                var aspectRatio = screenshot.aspectRatio
+                if aspectRatio.width > aspectRatio.height
+                {
+                    switch screenshot.deviceType
+                    {
+                    case .iphone:
+                        // Always rotate landscape iPhone screenshots
+                        aspectRatio = CGSize(width: aspectRatio.height, height: aspectRatio.width)
+                        
+                    case .ipad:
+                        // Never rotate iPad screenshots
+                        break
+                        
+                    default: break
+                    }
+                }
+                
+                let screenshotWidth = (layoutEnvironment.container.effectiveContentSize.height * (aspectRatio.width / aspectRatio.height)).rounded(.up) // Round to ensure we over-estimate contentWidth.
+                
+                let totalContentWidth = contentWidth + (screenshotWidth + minimumItemSpacing)
+                if totalContentWidth > layoutEnvironment.container.effectiveContentSize.width
+                {
+                    // totalContentWidth is larger than visible width.
+                    break
+                }
+                
+                contentWidth = totalContentWidth
+                numberOfVisibleScreenshots += 1
+            }
+            
+            // Use .estimated(1) to ensure we don't over-estimate widths, which can cause incorrect layouts for the last group.
+            let itemSize = NSCollectionLayoutSize(widthDimension: .estimated(1), heightDimension: .fractionalHeight(1.0))
+            
+            let item = NSCollectionLayoutItem(layoutSize: itemSize)
+            item.edgeSpacing = NSCollectionLayoutEdgeSpacing(leading: .flexible(0), top: nil, trailing: nil, bottom: nil)
+            
+            let groupItem = NSCollectionLayoutItem(layoutSize: itemSize)
+            let trailingGroup = NSCollectionLayoutGroup.horizontal(layoutSize: itemSize, subitems: [groupItem])
+            trailingGroup.edgeSpacing = NSCollectionLayoutEdgeSpacing(leading: nil, top: nil, trailing: .flexible(0), bottom: nil)
+            
+            let groupSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1.0), heightDimension: .fractionalHeight(1.0))
+            let group = NSCollectionLayoutGroup.horizontal(layoutSize: groupSize, subitems: [item, trailingGroup])
+            group.interItemSpacing = .fixed(minimumItemSpacing)
+            
+            if numberOfVisibleScreenshots < self.screenshots.count
+            {
+                // There are more screenshots than what is displayed, so no need to manually center them.
+            }
+            else
+            {
+                // We're showing all screenshots initially, so make sure they're centered.
+                
+                let insetWidth = (layoutEnvironment.container.effectiveContentSize.width - contentWidth) / 2.0
+                group.contentInsets.leading = (insetWidth - 1).rounded(.down) // Subtract 1 to avoid overflowing/clipping
+            }
+            
+            let layoutSection = NSCollectionLayoutSection(group: group)
+            layoutSection.orthogonalScrollingBehavior = .groupPagingCentered
+            layoutSection.interGroupSpacing = self.screenshotsCollectionView.directionalLayoutMargins.leading + self.screenshotsCollectionView.directionalLayoutMargins.trailing
+            return layoutSection
+        }, configuration: layoutConfig)
+        
+        return layout
+    }
+    
+    func makeDataSource() -> RSTArrayCollectionViewPrefetchingDataSource<AppScreenshot, UIImage>
+    {
+        let dataSource = RSTArrayCollectionViewPrefetchingDataSource<AppScreenshot, UIImage>(items: [])
+        dataSource.cellConfigurationHandler = { (cell, screenshot, indexPath) in
+            let cell = cell as! AppScreenshotCollectionViewCell
+            cell.imageView.image = nil
+            cell.imageView.isIndicatingActivity = true
+            
+            var aspectRatio = screenshot.aspectRatio
+            if aspectRatio.width > aspectRatio.height
+            {
+                switch screenshot.deviceType
+                {
+                case .iphone:
+                    // Always rotate landscape iPhone screenshots
+                    aspectRatio = CGSize(width: aspectRatio.height, height: aspectRatio.width)
+                    
+                case .ipad:
+                    // Never rotate iPad screenshots
+                    break
+                    
+                default: break
+                }
+            }
+            
+            cell.aspectRatio = aspectRatio
+        }
+        dataSource.prefetchHandler = { (screenshot, indexPath, completionHandler) in
+            let imageURL = screenshot.imageURL
+            return RSTAsyncBlockOperation() { (operation) in
+                let request = ImageRequest(url: imageURL)
+                ImagePipeline.shared.loadImage(with: request, progress: nil) { result in
+                    guard !operation.isCancelled else { return operation.finish() }
+                    
+                    switch result
+                    {
+                    case .success(let response): completionHandler(response.image, nil)
+                    case .failure(let error): completionHandler(nil, error)
+                    }
+                }
+            }
+        }
+        dataSource.prefetchCompletionHandler = { (cell, image, indexPath, error) in
+            let cell = cell as! AppScreenshotCollectionViewCell
+            cell.imageView.isIndicatingActivity = false
+            cell.setImage(image)
+            
+            if let error = error
+            {
+                print("Error loading image:", error)
+            }
+        }
+        
+        return dataSource
+    }
+    
+    @objc func handleTapGesture(_ tapGesture: UITapGestureRecognizer)
+    {
+        var superview: UIView? = self.superview
+        var collectionView: UICollectionView? = nil
+        
+        while case let view? = superview
+        {
+            if let cv = view as? UICollectionView
+            {
+                collectionView = cv
+                break
+            }
+            
+            superview = view.superview
+        }
+        
+        if let collectionView, let indexPath = collectionView.indexPath(for: self)
+        {
+            collectionView.delegate?.collectionView?(collectionView, didSelectItemAt: indexPath)
+        }
+    }
+}
+
+extension AppCardCollectionViewCell
+{
+    func configure(for storeApp: StoreApp)
+    {
+        self.screenshots = storeApp.preferredScreenshots()
+        
+        self.bannerView.tintColor = storeApp.tintColor
+        self.bannerView.configure(for: storeApp)
+        
+        self.bannerView.subtitleLabel.numberOfLines = 1
+        self.bannerView.subtitleLabel.lineBreakMode = .byTruncatingTail
+        self.bannerView.subtitleLabel.minimumScaleFactor = 0.8
+        self.bannerView.subtitleLabel.text = storeApp.subtitle ?? storeApp.developerName
+    }
+}