[Image Feed UI] Load Feed Logic/UX (MVC implementation)

EssentialFeed/EssentialFeed.xcodeproj/project.pbxproj

@@ -50,6 +50,11 @@
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 		EDF8FE522AE2470300605C5C /* FeedCachePolicy.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDF8FE512AE2470300605C5C /* FeedCachePolicy.swift */; };
+		EDFBE2402B10409C00EFB793 /* FeedViewControllerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDFBE23F2B10409C00EFB793 /* FeedViewControllerTests.swift */; };
+		EDFBE2422B1046C600EFB793 /* EssentialFeed.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 1438189629A135C0005B41C9 /* EssentialFeed.framework */; platformFilter = ios; };
+		EDFBE2432B1046C600EFB793 /* EssentialFeed.framework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = 1438189629A135C0005B41C9 /* EssentialFeed.framework */; platformFilter = ios; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
+		EDFBE2472B1048CF00EFB793 /* XCTTestCase + MemoryLeakTracking.swift in Sources */ = {isa = PBXBuildFile; fileRef = ED3FD1222A267833006299CD /* XCTTestCase + MemoryLeakTracking.swift */; };
+		EDFBE2492B10534300EFB793 /* FeedViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDFBE2482B10534300EFB793 /* FeedViewController.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -81,8 +86,29 @@
 			remoteGlobalIDString = 1438189529A135C0005B41C9;
 			remoteInfo = EssentialFeed;
 		};
+		EDFBE2442B1046C600EFB793 /* PBXContainerItemProxy */ = {
+			isa = PBXContainerItemProxy;
+			containerPortal = 1438188D29A135C0005B41C9 /* Project object */;
+			proxyType = 1;
+			remoteGlobalIDString = 1438189529A135C0005B41C9;
+			remoteInfo = EssentialFeed;
+		};
 /* End PBXContainerItemProxy section */
 
+/* Begin PBXCopyFilesBuildPhase section */
+		EDFBE2462B1046C700EFB793 /* Embed Frameworks */ = {
+			isa = PBXCopyFilesBuildPhase;
+			buildActionMask = 2147483647;
+			dstPath = "";
+			dstSubfolderSpec = 10;
+			files = (
+				EDFBE2432B1046C600EFB793 /* EssentialFeed.framework in Embed Frameworks */,
+			);
+			name = "Embed Frameworks";
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+/* End PBXCopyFilesBuildPhase section */
+
 /* Begin PBXFileReference section */
 		1438189629A135C0005B41C9 /* EssentialFeed.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = EssentialFeed.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		1438189929A135C0005B41C9 /* EssentialFeed.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = EssentialFeed.h; sourceTree = "<group>"; };
@@ -95,7 +121,7 @@
 		ED01EC782B01C5E900B405F4 /* EssentialFeedCacheIntegrationTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = EssentialFeedCacheIntegrationTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
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 		ED01EC822B01C70700B405F4 /* EssentialFeedCacheIntegrationTests.xctestplan */ = {isa = PBXFileReference; lastKnownFileType = text; path = EssentialFeedCacheIntegrationTests.xctestplan; sourceTree = SOURCE_ROOT; };
-		ED0EDEB52B0FAD55004857B7 /* EssentialFeedEndToEndTests.xctestplan */ = {isa = PBXFileReference; lastKnownFileType = file; path = EssentialFeedEndToEndTests.xctestplan; sourceTree = SOURCE_ROOT; };
+		ED0EDEB52B0FAD55004857B7 /* EssentialFeedEndToEndTests.xctestplan */ = {isa = PBXFileReference; lastKnownFileType = text; path = EssentialFeedEndToEndTests.xctestplan; sourceTree = SOURCE_ROOT; };
 		ED0EDEBB2B0FB680004857B7 /* EssentialFeediOS.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = EssentialFeediOS.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		ED0EDEC22B0FB681004857B7 /* EssentialFeediOSTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = EssentialFeediOSTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		ED0EDED02B0FB781004857B7 /* EssentialFeediOS.xctestplan */ = {isa = PBXFileReference; lastKnownFileType = text; path = EssentialFeediOS.xctestplan; sourceTree = "<group>"; };
@@ -131,6 +157,8 @@
 		EDF8FE4D2AE2389D00605C5C /* FeedCacheTestHelpers.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FeedCacheTestHelpers.swift; sourceTree = "<group>"; };
 		EDF8FE4F2AE2390B00605C5C /* SharedTestHelpers.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SharedTestHelpers.swift; sourceTree = "<group>"; };
 		EDF8FE512AE2470300605C5C /* FeedCachePolicy.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FeedCachePolicy.swift; sourceTree = "<group>"; };
+		EDFBE23F2B10409C00EFB793 /* FeedViewControllerTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FeedViewControllerTests.swift; sourceTree = "<group>"; };
+		EDFBE2482B10534300EFB793 /* FeedViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FeedViewController.swift; sourceTree = "<group>"; };
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 /* Begin PBXFrameworksBuildPhase section */
@@ -161,6 +189,7 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				EDFBE2422B1046C600EFB793 /* EssentialFeed.framework in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -194,6 +223,7 @@
 				ED0EDEBC2B0FB681004857B7 /* EssentialFeediOS */,
 				ED0EDEC62B0FB681004857B7 /* EssentialFeediOSTests */,
 				1438189729A135C0005B41C9 /* Products */,
+				EDFBE2412B1046C600EFB793 /* Frameworks */,
 			);
 			sourceTree = "<group>";
 		};
@@ -264,13 +294,15 @@
 		ED0EDEBC2B0FB681004857B7 /* EssentialFeediOS */ = {
 			isa = PBXGroup;
 			children = (
+				EDFBE2482B10534300EFB793 /* FeedViewController.swift */,
 			);
 			path = EssentialFeediOS;
 			sourceTree = "<group>";
 		};
 		ED0EDEC62B0FB681004857B7 /* EssentialFeediOSTests */ = {
 			isa = PBXGroup;
 			children = (
+				EDFBE23F2B10409C00EFB793 /* FeedViewControllerTests.swift */,
 			);
 			path = EssentialFeediOSTests;
 			sourceTree = "<group>";
@@ -380,6 +412,13 @@
 			path = FeedCache;
 			sourceTree = "<group>";
 		};
+		EDFBE2412B1046C600EFB793 /* Frameworks */ = {
+			isa = PBXGroup;
+			children = (
+			);
+			name = Frameworks;
+			sourceTree = "<group>";
+		};
 /* End PBXGroup section */
 
 /* Begin PBXHeadersBuildPhase section */
@@ -463,10 +502,12 @@
 				ED0EDEB72B0FB680004857B7 /* Sources */,
 				ED0EDEB82B0FB680004857B7 /* Frameworks */,
 				ED0EDEB92B0FB680004857B7 /* Resources */,
+				EDFBE2462B1046C700EFB793 /* Embed Frameworks */,
 			);
 			buildRules = (
 			);
 			dependencies = (
+				EDFBE2452B1046C600EFB793 /* PBXTargetDependency */,
 			);
 			name = EssentialFeediOS;
 			productName = EssentialFeediOS;
@@ -530,9 +571,11 @@
 					};
 					ED0EDEBA2B0FB680004857B7 = {
 						CreatedOnToolsVersion = 14.3.1;
+						LastSwiftMigration = 1430;
 					};
 					ED0EDEC12B0FB681004857B7 = {
 						CreatedOnToolsVersion = 14.3.1;
+						LastSwiftMigration = 1430;
 					};
 					ED555CD12A50045300447E9B = {
 						CreatedOnToolsVersion = 14.3;
@@ -669,13 +712,16 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				EDFBE2492B10534300EFB793 /* FeedViewController.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
 		ED0EDEBE2B0FB681004857B7 /* Sources */ = {
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				EDFBE2472B1048CF00EFB793 /* XCTTestCase + MemoryLeakTracking.swift in Sources */,
+				EDFBE2402B10409C00EFB793 /* FeedViewControllerTests.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -711,6 +757,12 @@
 			target = 1438189529A135C0005B41C9 /* EssentialFeed */;
 			targetProxy = ED555CD72A50045300447E9B /* PBXContainerItemProxy */;
 		};
+		EDFBE2452B1046C600EFB793 /* PBXTargetDependency */ = {
+			isa = PBXTargetDependency;
+			platformFilter = ios;
+			target = 1438189529A135C0005B41C9 /* EssentialFeed */;
+			targetProxy = EDFBE2442B1046C600EFB793 /* PBXContainerItemProxy */;
+		};
 /* End PBXTargetDependency section */
 
 /* Begin XCBuildConfiguration section */
@@ -861,6 +913,7 @@
 					"@executable_path/../Frameworks",
 					"@loader_path/Frameworks",
 				);
+				MACOSX_DEPLOYMENT_TARGET = 12.4;
 				MARKETING_VERSION = 1.0;
 				MODULE_VERIFIER_SUPPORTED_LANGUAGES = "objective-c objective-c++";
 				MODULE_VERIFIER_SUPPORTED_LANGUAGE_STANDARDS = "gnu11 gnu++20";
@@ -895,6 +948,7 @@
 					"@executable_path/../Frameworks",
 					"@loader_path/Frameworks",
 				);
+				MACOSX_DEPLOYMENT_TARGET = 12.4;
 				MARKETING_VERSION = 1.0;
 				MODULE_VERIFIER_SUPPORTED_LANGUAGES = "objective-c objective-c++";
 				MODULE_VERIFIER_SUPPORTED_LANGUAGE_STANDARDS = "gnu11 gnu++20";
@@ -980,6 +1034,7 @@
 		ED0EDECB2B0FB681004857B7 /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_STYLE = Automatic;
 				CURRENT_PROJECT_VERSION = 1;
 				DEFINES_MODULE = YES;
@@ -1005,6 +1060,7 @@
 				SDKROOT = iphoneos;
 				SKIP_INSTALL = YES;
 				SWIFT_EMIT_LOC_STRINGS = YES;
+				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
 				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};
@@ -1013,6 +1069,7 @@
 		ED0EDECC2B0FB681004857B7 /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_STYLE = Automatic;
 				CURRENT_PROJECT_VERSION = 1;
 				DEFINES_MODULE = YES;
@@ -1047,6 +1104,8 @@
 		ED0EDECE2B0FB681004857B7 /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
+				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_STYLE = Automatic;
 				CURRENT_PROJECT_VERSION = 1;
 				DEVELOPMENT_TEAM = WNFP74LNV2;
@@ -1057,6 +1116,7 @@
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = iphoneos;
 				SWIFT_EMIT_LOC_STRINGS = NO;
+				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
 				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};
@@ -1065,6 +1125,8 @@
 		ED0EDECF2B0FB681004857B7 /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
+				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_STYLE = Automatic;
 				CURRENT_PROJECT_VERSION = 1;
 				DEVELOPMENT_TEAM = WNFP74LNV2;

EssentialFeed/EssentialFeediOS/FeedViewController.swift

@@ -0,0 +1,33 @@
+//
+//  FeedViewController.swift
+//  EssentialFeediOS
+//
+//  Created by Oluwaseun Adebanwo on 24/11/2023.
+//
+
+import UIKit
+import EssentialFeed
+
+final public class FeedViewController: UITableViewController {
+    private var loader: FeedLoader?
+
+    public convenience init(loader: FeedLoader) {
+        self.init()
+        self.loader = loader
+    }
+
+    public override func viewDidLoad() {
+        super.viewDidLoad()
+
+        refreshControl = UIRefreshControl()
+        refreshControl?.addTarget(self, action: #selector(load), for: .valueChanged)
+        load()
+    }
+
+    @objc private func load() {
+        refreshControl?.beginRefreshing()
+        loader?.load { [weak self] _ in
+            self?.refreshControl?.endRefreshing()
+        }
+    }
+}

EssentialFeed/EssentialFeediOSTests/FeedViewControllerTests.swift

@@ -0,0 +1,93 @@
+//
+//  FeedViewControllerTests.swift
+//  EssentialFeediOSTests
+//
+//  Created by Oluwaseun Adebanwo on 24/11/2023.
+//
+
+import XCTest
+import UIKit
+import EssentialFeed
+import EssentialFeediOS
+
+final class FeedViewControllerTests: XCTestCase {
+
+    func test_loadFeedActions_requestFeedFromLoader() {
+        let (sut, loader) = makeSUT()
+
+        XCTAssertEqual(loader.loadCallCount, 0, "Expected no loading requests before view is loaded")
+
+        sut.loadViewIfNeeded()
+
+        XCTAssertEqual(loader.loadCallCount, 1, "Expected a loading request once view is loaded")
+
+        sut.simulateUserInitiatedFeedReload()
+        XCTAssertEqual(loader.loadCallCount, 2, "Expected another loading request once user initiates a reload")
+
+        sut.simulateUserInitiatedFeedReload()
+        XCTAssertEqual(loader.loadCallCount, 3, "Expected yet another loading request once user initiates another reload")
+    }
+
+    func test_loadingFeedIndicator_isVisibleWhileLoadingFeed() {
+        let (sut, loader) = makeSUT()
+
+        sut.loadViewIfNeeded()
+        XCTAssertTrue(sut.isShowingLoadingIndicator, "Expected loading indicator once view is loaded")
+
+        loader.completeFeedLoading(at: 0)
+        XCTAssertFalse(sut.isShowingLoadingIndicator, "Expected no loading indicator once loading is completed")
+
+        sut.simulateUserInitiatedFeedReload()
+        XCTAssertTrue(sut.isShowingLoadingIndicator, "Expected loading indicator once user initiates a reload")
+
+        loader.completeFeedLoading(at: 1)
+        XCTAssertFalse(sut.isShowingLoadingIndicator, "Expected no loading indicator once user initiated loading is completed")
+    }
+
+    // MARK: - Helpers
+
+    private func makeSUT(file: StaticString = #file, line: UInt = #line) -> (sut: FeedViewController, loader: LoaderSpy) {
+        let loader = LoaderSpy()
+        let sut = FeedViewController(loader: loader)
+        trackForMemoryLeaks(loader, file: file, line: line)
+        trackForMemoryLeaks(sut, file: file, line: line)
+        return (sut, loader)
+    }
+
+    class LoaderSpy: FeedLoader {
+        private var completions = [(FeedLoader.Result) -> Void]()
+
+        var loadCallCount: Int {
+            return completions.count
+        }
+
+        func load(completion: @escaping (FeedLoader.Result) -> Void) {
+            completions.append(completion)
+        }
+
+        func completeFeedLoading(at index: Int) {
+            completions[index](.success([]))
+        }
+    }
+
+}
+
+private extension FeedViewController {
+    func simulateUserInitiatedFeedReload() {
+        refreshControl?.simulatePullToRefresh()
+    }
+
+    var isShowingLoadingIndicator: Bool {
+        return refreshControl?.isRefreshing == true
+    }
+}
+
+private extension UIRefreshControl {
+    func simulatePullToRefresh() {
+        allTargets.forEach { target in
+            actions(forTarget: target, forControlEvent: .valueChanged)?.forEach {
+                (target as NSObject).perform(Selector($0))
+            }
+        }
+    }
+}

Prototype/Prototype/Base.lproj/Main.storyboard

@@ -115,6 +115,7 @@ Location</string>
                                 </tableViewCellContentView>
                                 <connections>
                                     <outlet property="descriptionLabel" destination="yO0-i3-0sk" id="Glw-Ya-AzV"/>
+                                    <outlet property="feedImageContainer" destination="QIx-nZ-8ow" id="lq9-sx-Anm"/>
                                     <outlet property="feedImageView" destination="XIW-mQ-UHo" id="EqY-bf-evu"/>
                                     <outlet property="locationContainer" destination="zi1-l0-PUS" id="Sty-bL-VKV"/>
                                     <outlet property="locationLabel" destination="cec-Ly-ymI" id="UZI-cm-cVC"/>
@@ -127,6 +128,12 @@ Location</string>
                         </connections>
                     </tableView>
                     <navigationItem key="navigationItem" title="My Feed" id="Y8p-eb-UyB"/>
+                    <refreshControl key="refreshControl" opaque="NO" multipleTouchEnabled="YES" contentMode="center" insetsLayoutMarginsFromSafeArea="NO" enabled="NO" contentHorizontalAlignment="center" contentVerticalAlignment="center" id="mu9-S9-Yda">
+                        <autoresizingMask key="autoresizingMask"/>
+                        <connections>
+                            <action selector="refresh" destination="zKj-AM-8g9" eventType="valueChanged" id="wjp-V2-Xel"/>
+                        </connections>
+                    </refreshControl>
                 </tableViewController>
                 <placeholder placeholderIdentifier="IBFirstResponder" id="bm8-KC-aUT" userLabel="First Responder" customClass="UIResponder" sceneMemberID="firstResponder"/>
             </objects>