Cleanup and fixes for CollectionViewDriver

- remove hidden supplementary view hacks, close #47 - fix `SupplementaryViewKind` models, close #56 - `RegistrationMethod` --> `ViewRegistrationMethod` (and remove nesting, since this will apply to all cells in #18) - make `kind` a property of `SupplementaryViewInfo` - Remove `typealias Section`, only used in one place and doesn't add any value
plangrid · Jan 25, 2018 · 1c2e8d1 · 1c2e8d1
1 parent 766e31a
commit 1c2e8d1
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Showing 10 changed files with 63 additions and 50 deletions.
diff --git a/Example/CollectionViewController.swift b/Example/CollectionViewController.swift
@@ -83,6 +83,7 @@ extension CollectionViewController {
                 viewInfo: SupplementaryViewInfo(
                     registrationMethod: .nib(name: "CollectionViewHeaderView", bundle: nil),
                     reuseIdentifier: "CollectionViewHeaderView",
+                    kind: .header,
                     accessibilityFormat: "CollectionViewHeaderView"
                 )
             )

diff --git a/ReactiveLists.xcodeproj/project.pbxproj b/ReactiveLists.xcodeproj/project.pbxproj
@@ -36,6 +36,7 @@
 		258E31D41F0D8F3100D6F324 /* SupplementaryViewInfo.swift in Sources */ = {isa = PBXBuildFile; fileRef = 258E31D21F0D8F3100D6F324 /* SupplementaryViewInfo.swift */; };
 		25B1B0B920195F1C0036545F /* CollectionViewDriverDiffingTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 25B1B0B720195F160036545F /* CollectionViewDriverDiffingTests.swift */; };
 		25B1B0BA201A53CF0036545F /* Typealiases.swift in Sources */ = {isa = PBXBuildFile; fileRef = 32124A712019312200EE12FC /* Typealiases.swift */; };
+		32E7A1F4201A7F3500B90EBC /* ViewRegistrationMethod.swift in Sources */ = {isa = PBXBuildFile; fileRef = 32E7A1F3201A7F3500B90EBC /* ViewRegistrationMethod.swift */; };
 		351B0BB920168E2E0034569D /* CollectionViewCells.swift in Sources */ = {isa = PBXBuildFile; fileRef = 351B0BB420168D2E0034569D /* CollectionViewCells.swift */; };
 		351B0BBA20168E2E0034569D /* CollectionViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 351B0BB320168D2E0034569D /* CollectionViewController.swift */; };
 		357B96DA201934C50000443F /* CollectionToolCell.xib in Resources */ = {isa = PBXBuildFile; fileRef = 357B96D9201934C50000443F /* CollectionToolCell.xib */; };
@@ -114,6 +115,7 @@
 		276442FEC917A7E0F32CE5B4 /* Pods-ReactiveLists-ReactiveListsExample.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-ReactiveLists-ReactiveListsExample.debug.xcconfig"; path = "Pods/Target Support Files/Pods-ReactiveLists-ReactiveListsExample/Pods-ReactiveLists-ReactiveListsExample.debug.xcconfig"; sourceTree = "<group>"; };
 		2F35530D29268B112F99A187 /* Pods_ReactiveLists_ReactiveListsExample.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_ReactiveLists_ReactiveListsExample.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		32124A712019312200EE12FC /* Typealiases.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Typealiases.swift; sourceTree = "<group>"; };
+		32E7A1F3201A7F3500B90EBC /* ViewRegistrationMethod.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ViewRegistrationMethod.swift; sourceTree = "<group>"; };
 		351B0BB320168D2E0034569D /* CollectionViewController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = CollectionViewController.swift; sourceTree = "<group>"; };
 		351B0BB420168D2E0034569D /* CollectionViewCells.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = CollectionViewCells.swift; sourceTree = "<group>"; };
 		357B96D9201934C50000443F /* CollectionToolCell.xib */ = {isa = PBXFileReference; lastKnownFileType = file.xib; path = CollectionToolCell.xib; sourceTree = "<group>"; };
@@ -262,6 +264,7 @@
 				258E31AE1F0D8D9C00D6F324 /* TableViewDriver.swift */,
 				258E31AF1F0D8D9C00D6F324 /* TableViewModel.swift */,
 				32124A712019312200EE12FC /* Typealiases.swift */,
+				32E7A1F3201A7F3500B90EBC /* ViewRegistrationMethod.swift */,
 			);
 			path = Sources;
 			sourceTree = "<group>";
@@ -616,6 +619,7 @@
 			files = (
 				2541B73D1F29A13B002C3090 /* Diffing.swift in Sources */,
 				258E31B31F0D8D9C00D6F324 /* TableViewDriver.swift in Sources */,
+				32E7A1F4201A7F3500B90EBC /* ViewRegistrationMethod.swift in Sources */,
 				258E31B11F0D8D9C00D6F324 /* CollectionViewDriver.swift in Sources */,
 				258E31B41F0D8D9C00D6F324 /* TableViewModel.swift in Sources */,
 				258E31D31F0D8F3100D6F324 /* AccessibilityFormats.swift in Sources */,

diff --git a/Sources/AccessibilityFormats.swift b/Sources/AccessibilityFormats.swift
@@ -63,7 +63,7 @@ public struct SupplementaryAccessibilityFormat: ExpressibleByStringLiteral {
         self._format = value
     }
 
-    public func accessibilityIdentifierForSection(_ section: Section) -> String {
+    public func accessibilityIdentifierForSection(_ section: Int) -> String {
         return self._format.replacingOccurrences(of: "%{section}", with: String(section))
     }
 }
diff --git a/Sources/CollectionViewDriver.swift b/Sources/CollectionViewDriver.swift
@@ -57,7 +57,6 @@ public class CollectionViewDriver: NSObject, UICollectionViewDataSource, UIColle
     private var _shouldDeselectUponSelection: Bool
     private var _collectionViewDiffer: CollectionViewDiffCalculator<DiffingKey, DiffingKey>?
     private var _didReceiveFirstNonNilValue = false
-    private static let _hiddenSupplementaryViewIdentifier = "hidden-supplementary-view"
 
     /// Initializes a data source that drives a `UICollectionView` based on a `CollectionViewModel`.
     ///
@@ -131,7 +130,6 @@ public class CollectionViewDriver: NSObject, UICollectionViewDataSource, UIColle
 
     private func _collectionViewModelDidChange() {
         self._registerSupplementaryViews()
-        self._registerHiddenSupplementaryViews()
 
         guard let newModel = self.collectionViewModel else {
             self.refreshViews()
@@ -196,10 +194,10 @@ public class CollectionViewDriver: NSObject, UICollectionViewDataSource, UIColle
             view = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: identifier, for: indexPath)
             viewModel.applyViewModelToView(view)
             view.accessibilityIdentifier = viewModel.viewInfo?.accessibilityFormat.accessibilityIdentifierForSection(section)
-        } else {
-            view = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: CollectionViewDriver._hiddenSupplementaryViewIdentifier, for: indexPath)
+            return view
         }
-        return view
+
+        fatalError("Invalid supplementary view and layout configuration")
     }
 
     public func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
@@ -254,16 +252,6 @@ public class CollectionViewDriver: NSObject, UICollectionViewDataSource, UIColle
         }
     }
 
-    private func _registerHiddenSupplementaryViews() {
-        // A blank header/footer view class must be registered because `viewForSupplementaryElementOfKind` returns
-        // a non-optional view and yet the `collectionViewModel` may not specify some headers and footers
-        [UICollectionElementKindSectionHeader, UICollectionElementKindSectionFooter].forEach {
-            collectionView.register(UICollectionReusableView.self,
-                                     forSupplementaryViewOfKind: $0,
-                                     withReuseIdentifier: CollectionViewDriver._hiddenSupplementaryViewIdentifier)
-        }
-    }
-
     private func _sizeForSupplementaryViewOfKind(_ elementKind: SupplementaryViewKind, inSection section: Int, collectionViewLayout: UICollectionViewLayout) -> CGSize {
         guard let sectionModel = self.collectionViewModel?[section] else {
             return CGSize.zero

diff --git a/Sources/SupplementaryViewInfo.swift b/Sources/SupplementaryViewInfo.swift
@@ -18,37 +18,24 @@ import Foundation
 import UIKit
 
 public struct SupplementaryViewInfo {
-    /// The method for registering the supplementary view
-    public enum RegistrationMethod: Equatable {
-        /// Class-based views
-        case viewClass(AnyClass)
-        /// Nib-based views
-        case nib(name: String, bundle: Bundle?)
 
-        public static func == (lhs: RegistrationMethod, rhs: RegistrationMethod) -> Bool {
-            switch (lhs, rhs) {
-            case let (.viewClass(lhsClass), .viewClass(rhsClass)):
-                return lhsClass == rhsClass
-            case let (.nib(lhsName, lhsBundle), .nib(rhsName, rhsBundle)):
-                return lhsName == rhsName && lhsBundle == rhsBundle
-            default:
-                return false
-            }
-        }
-    }
+    public let registrationMethod: ViewRegistrationMethod
+
+    public let reuseIdentifier: String
+
+    public let kind: SupplementaryViewKind
 
-    let registrationMethod: RegistrationMethod
-    let reuseIdentifier: String
-    /// `TableViewDataSource` and `CollectionViewDataSource` will automatically apply an `accessibilityIdentifier` to the supplementary view based on this format
-    let accessibilityFormat: SupplementaryAccessibilityFormat
+    /// `TableViewDataSource` and `CollectionViewDataSource` will automatically apply
+    /// an `accessibilityIdentifier` to the supplementary view based on this format
+    public let accessibilityFormat: SupplementaryAccessibilityFormat
 
-    public init(
-        registrationMethod: RegistrationMethod,
-        reuseIdentifier: String,
-        accessibilityFormat: SupplementaryAccessibilityFormat
-    ) {
+    public init(registrationMethod: ViewRegistrationMethod,
+                reuseIdentifier: String,
+                kind: SupplementaryViewKind,
+                accessibilityFormat: SupplementaryAccessibilityFormat) {
         self.registrationMethod = registrationMethod
         self.reuseIdentifier = reuseIdentifier
+        self.kind = kind
         self.accessibilityFormat = accessibilityFormat
     }
 }

diff --git a/Sources/Typealiases.swift b/Sources/Typealiases.swift
@@ -16,8 +16,6 @@
 
 import Foundation
 
-public typealias Section = Int
-
 public typealias CommitEditingStyleClosure = (UITableViewCellEditingStyle) -> Void
 public typealias DidSelectClosure = () -> Void
 public typealias DidDeleteClosure = () -> Void

diff --git a/Sources/ViewRegistrationMethod.swift b/Sources/ViewRegistrationMethod.swift
@@ -0,0 +1,38 @@
+//
+//  PlanGrid
+//  https://www.plangrid.com
+//  https://medium.com/plangrid-technology
+//
+//  Documentation
+//  https://plangrid.github.io/ReactiveLists
+//
+//  GitHub
+//  https://github.com/plangrid/ReactiveLists
+//
+//  License
+//  Copyright © 2018-present PlanGrid, Inc.
+//  Released under an MIT license: https://opensource.org/licenses/MIT
+// 
+
+import Foundation
+
+/// The method for registering cells and supplementary views
+public enum ViewRegistrationMethod {
+    /// Class-based views
+    case viewClass(AnyClass)
+    /// Nib-based views
+    case nib(name: String, bundle: Bundle?)
+}
+
+extension ViewRegistrationMethod: Equatable {
+    public static func == (lhs: ViewRegistrationMethod, rhs: ViewRegistrationMethod) -> Bool {
+        switch (lhs, rhs) {
+        case let (.viewClass(lhsClass), .viewClass(rhsClass)):
+            return lhsClass == rhsClass
+        case let (.nib(lhsName, lhsBundle), .nib(rhsName, rhsBundle)):
+            return lhsName == rhsName && lhsBundle == rhsBundle
+        default:
+            return false
+        }
+    }
+}
diff --git a/Tests/CollectionView/CollectionViewDriverTests.swift b/Tests/CollectionView/CollectionViewDriverTests.swift
@@ -62,16 +62,11 @@ final class CollectionViewDriverTests: XCTestCase {
 
         // Test that header and footer view classes explicitly provided in the view model are registered
         let registerCalls = self._collectionView.callsToRegisterClass
-        XCTAssertEqual(registerCalls.count, 6)
+        XCTAssertEqual(registerCalls.count, 4)
         self._testRegisterClassCallInfo(registerCalls[0], viewClass: HeaderView.self, kind: .header, identifier: "reuse_header+A")
         self._testRegisterClassCallInfo(registerCalls[1], viewClass: FooterView.self, kind: .footer, identifier: "reuse_footer+A")
         self._testRegisterClassCallInfo(registerCalls[2], viewClass: HeaderView.self, kind: .header, identifier: "reuse_header+D")
         self._testRegisterClassCallInfo(registerCalls[3], viewClass: FooterView.self, kind: .footer, identifier: "reuse_footer+D")
-
-        // Test that the a blank header and footer view class is registered for hidden headers and footers
-        // Used for headers and footers that are not explicitly provided in the view model
-        self._testRegisterClassCallInfo(registerCalls[4], viewClass: UICollectionReusableView.self, kind: .header, identifier: "hidden-supplementary-view")
-        self._testRegisterClassCallInfo(registerCalls[5], viewClass: UICollectionReusableView.self, kind: .footer, identifier: "hidden-supplementary-view")
     }
 
     func testCollectionViewSections() {

diff --git a/Tests/Fixtures/TestCollectionViewModels.swift b/Tests/Fixtures/TestCollectionViewModels.swift
@@ -50,6 +50,7 @@ struct TestCollectionViewSupplementaryViewModel: CollectionViewSupplementaryView
         self.viewInfo = SupplementaryViewInfo(
             registrationMethod: .viewClass(viewKind == .header ? HeaderView.self : FooterView.self),
             reuseIdentifier: "reuse_\(kindString)+\(sectionLabel)", // e.g. reuse_header+A
+            kind: viewKind,
             accessibilityFormat: SupplementaryAccessibilityFormat("access_\(kindString)+%{section}")) // e.g. access_header+%{section}
     }
 

diff --git a/Tests/Fixtures/TestTableViewModels.swift b/Tests/Fixtures/TestTableViewModels.swift
@@ -99,6 +99,7 @@ struct TestHeaderFooterViewModel: TableViewSectionHeaderFooterViewModel {
         self.viewInfo = SupplementaryViewInfo(
             registrationMethod: .viewClass(viewKind == .header ? HeaderView.self : FooterView.self),
             reuseIdentifier: "reuse_\(kindString)+\(label)", // e.g. reuse_header_3
+            kind: viewKind,
             accessibilityFormat: SupplementaryAccessibilityFormat("access_\(kindString)+%{section}")) // e.g. access_header+%{section}
     }