added NewCommonCollectionViewHandler that uses diffable data source

Author: danny

OnoKit.xcodeproj/project.pbxproj

@@ -7,6 +7,7 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		76FBC99427D7B864005FE78E /* NewCommonCollectionViewHandler.swift in Sources */ = {isa = PBXBuildFile; fileRef = 76FBC99327D7B864005FE78E /* NewCommonCollectionViewHandler.swift */; };
 		770456EC251522F1006CC071 /* Common.h in Headers */ = {isa = PBXBuildFile; fileRef = 770456EA251522F1006CC071 /* Common.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		7704570525152373006CC071 /* UINavigationControllerExtension.swift in Sources */ = {isa = PBXBuildFile; fileRef = 770456F625152372006CC071 /* UINavigationControllerExtension.swift */; };
 		7704570625152373006CC071 /* UIButtonExtension.swift in Sources */ = {isa = PBXBuildFile; fileRef = 770456F725152372006CC071 /* UIButtonExtension.swift */; };
@@ -83,6 +84,7 @@
 		55A9E3F1689CD6C95BE0112C /* Pods_OnoKit.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_OnoKit.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		678736D52C2FCD745E0D3315 /* Pods-OnoKit.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-OnoKit.debug.xcconfig"; path = "Target Support Files/Pods-OnoKit/Pods-OnoKit.debug.xcconfig"; sourceTree = "<group>"; };
 		7020874F68DD9D1C4D9477CE /* Pods-OnoKit.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-OnoKit.release.xcconfig"; path = "Target Support Files/Pods-OnoKit/Pods-OnoKit.release.xcconfig"; sourceTree = "<group>"; };
+		76FBC99327D7B864005FE78E /* NewCommonCollectionViewHandler.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NewCommonCollectionViewHandler.swift; sourceTree = "<group>"; };
 		770456E7251522F1006CC071 /* OnoKit.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = OnoKit.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		770456EA251522F1006CC071 /* Common.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = Common.h; sourceTree = "<group>"; };
 		770456EB251522F1006CC071 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
@@ -226,6 +228,7 @@
 				77045716251523BD006CC071 /* CommonButton.swift */,
 				77045718251523BD006CC071 /* CommonCollectionView.swift */,
 				77045717251523BD006CC071 /* CommonCollectionViewHandler.swift */,
+				76FBC99327D7B864005FE78E /* NewCommonCollectionViewHandler.swift */,
 				7704571D251523BD006CC071 /* CommonDateFormatter.swift */,
 				7704571C251523BD006CC071 /* CommonImageView.swift */,
 				7704571F251523BE006CC071 /* CommonLabel.swift */,
@@ -503,6 +506,7 @@
 				7704571125152373006CC071 /* UILabelExtension.swift in Sources */,
 				774D019B251B0541005F35B2 /* UIFontExtension.swift in Sources */,
 				77045726251523BE006CC071 /* CommonTextField.swift in Sources */,
+				76FBC99427D7B864005FE78E /* NewCommonCollectionViewHandler.swift in Sources */,
 				776F6E75251ACE6200C1A84B /* CommonFontManager.swift in Sources */,
 				77E9AEEF25198A7E002A8538 /* ExampleViewModel.swift in Sources */,
 				7704575625152523006CC071 /* CommonViewModel.swift in Sources */,

OnoKit/Classes/NewCommonCollectionViewHandler.swift

@@ -0,0 +1,69 @@
+//
+//  NewCommonCollectionViewHandler.swift
+//  OnoKit
+//
+//  Created by Danny on 3/7/22.
+//
+
+import UIKit
+
+open class NewCommonCollectionViewHandler: NSObject, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout {
+    private lazy var dataSource = makeDataSource()
+
+    typealias DataSource = UICollectionViewDiffableDataSource<AnyHashable, AnyHashable>
+    typealias Snapshot = NSDiffableDataSourceSnapshot<AnyHashable, AnyHashable>
+
+    let collectionView: UICollectionView
+
+    init(_ collectionView: UICollectionView) {
+        self.collectionView = collectionView
+        super.init()
+
+        collectionView.delegate = self
+    }
+
+    open func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
+        return .zero
+    }
+
+    open func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
+        return .zero
+    }
+
+    // needs overridden by subclass
+    open func collectionViewHandler(cellForItemAt indexPath: IndexPath, itemIdentifier: AnyHashable) -> UICollectionViewCell? {
+        return nil
+    }
+
+    open func collectionViewHandlerSections() -> [AnyHashable] {
+        return []
+    }
+
+    open func collectionViewHandler(itemIdentifiersFor section: AnyHashable) -> [AnyHashable] {
+        return []
+    }
+
+    private func makeDataSource() -> DataSource {
+        let dataSource = DataSource(collectionView: collectionView) { _, indexPath, itemIdentifer in
+            let cell = self.collectionViewHandler(cellForItemAt: indexPath, itemIdentifier: itemIdentifer)
+
+            return cell
+        }
+
+        return dataSource
+    }
+
+    public func applySnapshot(animatingDifferences: Bool) {
+        var snapshot = Snapshot()
+
+        let sections = self.collectionViewHandlerSections()
+        snapshot.appendSections(sections)
+
+        for section in sections {
+            let identifiers = self.collectionViewHandler(itemIdentifiersFor: section)
+            snapshot.appendItems(identifiers, toSection: section)
+        }
+
+        dataSource.apply(snapshot, animatingDifferences: animatingDifferences)
+    }
+}

OnoKit/Extensions/UICollectionViewExtension.swift

@@ -10,6 +10,7 @@ public extension UICollectionView {
 
     // MARK: - Common Creators
 
+    @available(*, deprecated, message: "Use NewCommonCollectionViewHandler instead.")
     convenience init(_ superview: UIView, _ direction: UICollectionView.ScrollDirection, _ handler: CommonCollectionViewHandler, _ identifiers: [String]) {
 
         let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
@@ -41,4 +42,30 @@ public extension UICollectionView {
 
     }
 
+    convenience init(_ superview: UIView, _ direction: UICollectionView.ScrollDirection, _ identifiers: [String]) {
+        
+        let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
+        layout.scrollDirection = direction
+        
+        self.init(frame: .zero, collectionViewLayout: layout)
+        
+        self.backgroundColor = .clear
+        
+        self.showsVerticalScrollIndicator = false
+        self.showsHorizontalScrollIndicator = false
+        
+        self.isPagingEnabled = true
+        self.bounces = false
+        
+        for identifier in identifiers {
+            if let projectName = Bundle.main.infoDictionary!["CFBundleExecutable"] as? String {
+                let namespace = projectName.replacingOccurrences(of: "-", with: "_")
+                if let anyClass: AnyClass = NSClassFromString("\(namespace).\(identifier)") {
+                    self.register(anyClass, forCellWithReuseIdentifier: identifier)
+                }
+            }
+        }
+        
+        superview.addSubview(self)
+    }
 }