Toggle UIButton based on Model.selected value

RxCollectionViewTester.xcodeproj/project.pbxproj

@@ -8,6 +8,7 @@
 
 /* Begin PBXBuildFile section */
 		72C204D821E0E021003F09A4 /* ViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 72C204D721E0E021003F09A4 /* ViewModel.swift */; };
+		B330E16621EE6E7400CB161E /* Repository.swift in Sources */ = {isa = PBXBuildFile; fileRef = B330E16521EE6E7300CB161E /* Repository.swift */; };
 		B3C3512521DEB56F009AC5A3 /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = B3C3512421DEB56F009AC5A3 /* AppDelegate.swift */; };
 		B3C3512721DEB56F009AC5A3 /* ViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = B3C3512621DEB56F009AC5A3 /* ViewController.swift */; };
 		B3C3512A21DEB56F009AC5A3 /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = B3C3512821DEB56F009AC5A3 /* Main.storyboard */; };
@@ -20,6 +21,7 @@
 		72C204D721E0E021003F09A4 /* ViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ViewModel.swift; sourceTree = "<group>"; };
 		972E1ADCA05CCA7395450042 /* Pods_RxCollectionViewTester.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_RxCollectionViewTester.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		9782C688C2D76C1E1D0AB269 /* Pods-RxCollectionViewTester.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-RxCollectionViewTester.debug.xcconfig"; path = "Pods/Target Support Files/Pods-RxCollectionViewTester/Pods-RxCollectionViewTester.debug.xcconfig"; sourceTree = "<group>"; };
+		B330E16521EE6E7300CB161E /* Repository.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Repository.swift; sourceTree = "<group>"; };
 		B3C3512121DEB56F009AC5A3 /* RxCollectionViewTester.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = RxCollectionViewTester.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		B3C3512421DEB56F009AC5A3 /* AppDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
 		B3C3512621DEB56F009AC5A3 /* ViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ViewController.swift; sourceTree = "<group>"; };
@@ -72,12 +74,13 @@
 			isa = PBXGroup;
 			children = (
 				B3C3512421DEB56F009AC5A3 /* AppDelegate.swift */,
+				B330E16521EE6E7300CB161E /* Repository.swift */,
 				B3C3512621DEB56F009AC5A3 /* ViewController.swift */,
 				72C204D721E0E021003F09A4 /* ViewModel.swift */,
-				B3C3512821DEB56F009AC5A3 /* Main.storyboard */,
 				B3C3512B21DEB570009AC5A3 /* Assets.xcassets */,
-				B3C3512D21DEB570009AC5A3 /* LaunchScreen.storyboard */,
 				B3C3513021DEB570009AC5A3 /* Info.plist */,
+				B3C3512D21DEB570009AC5A3 /* LaunchScreen.storyboard */,
+				B3C3512821DEB56F009AC5A3 /* Main.storyboard */,
 			);
 			path = RxCollectionViewTester;
 			sourceTree = "<group>";
@@ -224,6 +227,7 @@
 				B3C3512721DEB56F009AC5A3 /* ViewController.swift in Sources */,
 				72C204D821E0E021003F09A4 /* ViewModel.swift in Sources */,
 				B3C3512521DEB56F009AC5A3 /* AppDelegate.swift in Sources */,
+				B330E16621EE6E7400CB161E /* Repository.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

RxCollectionViewTester/Repository.swift

@@ -0,0 +1,29 @@
+//
+//  Repository.swift
+//  RxCollectionViewTester
+//
+//  Created by Rui Rodrigues on 15/01/2019.
+//  Copyright © 2019 brownie. All rights reserved.
+//
+
+import Foundation
+
+struct Model {
+    let id = UUID()
+    var value: Int
+    var selected: Bool = Bool.random()
+
+    init(_ v: Int) {
+        self.value = v
+    }
+}
+
+class Repository {
+
+    func refreshValues() -> [Model] {
+        return (0..<20)
+            .map { _ in Int.random(in: 0..<100) }
+            .map { Model($0) }
+    }
+
+}

RxCollectionViewTester/ViewController.swift

@@ -32,6 +32,8 @@ class ViewController: UIViewController {
 
     let bag = DisposeBag()
 
+    let repository = Repository()
+
     let generateButton = UIButton.withTitle("Generate")
     let showAllButton = UIButton.withTitle("Show All")
     let removeAllButton = UIButton.withTitle("Remove All")
@@ -45,6 +47,7 @@ class ViewController: UIViewController {
     }()
 
     let value = PublishSubject<(id: UUID, value: Int)>()
+    let selectedChanged = PublishSubject<(id: UUID, selected: Bool)>()
     let delete = PublishSubject<UUID>()
 
     override func viewDidLoad() {
@@ -83,23 +86,30 @@ class ViewController: UIViewController {
         // the two lines below are so we can avoid dealing with self in the closure.
         let value = self.value
         let delete = self.delete
-
+        let selectedChanged = self.selectedChanged
+
         let input = Input(
             value: value,
+            selectedChanged: selectedChanged,
             add: generateButton.rx.tap.asObservable(),
             delete: delete
         )
-        let viewModel = ViewModel(input, initialValues: [])
+        let viewModel = ViewModel(input, refreshTask: self.repository.refreshValues)
 
         viewModel.counters
             .bind(to: collectionView.rx.items(cellIdentifier: CollectionViewCell.identifier, cellType: CollectionViewCell.self)) { index, element, cell in
                 cell.configure(with: { input in
-                    let vm = CellViewModel(input, initialValue: element.value)
+                    let vm = CellViewModel(input, initialValue: element)
                     // Remember the value property tracks the current value of the counter
                     vm.value
                         .map { (id: element.id, value: $0) } // tell the main view model which counter's value this is
                         .bind(to: value)
                         .disposed(by: cell.bag)
+
+                    vm.selectedChanged
+                        .map { (id: element.id, selected: $0)}
+                        .bind(to: selectedChanged)
+                        .disposed(by: cell.bag)
 
                     vm.delete
                         .map { element.id } // tell the main view model which counter should be deleted
@@ -189,6 +199,7 @@ class CollectionViewCell: UICollectionViewCell {
         let input = CellInput(
             plus: plus.rx.tap.asObservable(),
             minus: minus.rx.tap.asObservable(),
+            select: check.rx.tap.asObservable(),
             delete: delete.rx.tap.asObservable()
         )
         // create the view model from the factory
@@ -197,6 +208,10 @@ class CollectionViewCell: UICollectionViewCell {
         viewModel.label
             .bind(to: label.rx.text)
             .disposed(by: bag)
+
+        viewModel.selected
+            .bind(to: check.rx.isSelected)
+            .disposed(by: bag)
     }
 
     override func prepareForReuse() {

RxCollectionViewTester/ViewModel.swift

@@ -11,37 +11,43 @@ import RxSwift
 
 struct Input {
 	let value: Observable<(id: UUID, value: Int)>
+    let selectedChanged: Observable<(id: UUID, selected: Bool)>
 	let add: Observable<Void>
 	let delete: Observable<UUID>
 }
 
 struct ViewModel {
-	let counters: Observable<[(id: UUID, value: Int)]>
+	let counters: Observable<[Model]>
 }
 
 extension ViewModel {
 	private enum Action {
 		case add
 		case value(id: UUID, value: Int)
+        case selectedChanged(id: UUID, selected: Bool)
 		case delete(id: UUID)
 	}
 
-	init(_ input: Input, initialValues: [(id: UUID, value: Int)]) {
+	init(_ input: Input, refreshTask: @escaping () -> [Model]) {
 		let addAction = input.add.map { Action.add }
 		let valueAction = input.value.map(Action.value)
+        let selectedChangedAction = input.selectedChanged.map(Action.selectedChanged)
 		let deleteAction = input.delete.map(Action.delete)
-		counters = Observable.merge(addAction, valueAction, deleteAction)
+
+		counters = Observable.merge(addAction, valueAction, selectedChangedAction, deleteAction)
             .startWith(.add)
-			.scan(into: initialValues) { model, new in
+			.scan(into: []) { model, new in
 				switch new {
 				case .add:
-                    model = (0..<20)
-                        .map { _ in Int.random(in: 0..<100) }
-                        .map { (UUID(), $0) }
+                    model = refreshTask()
 				case .value(let id, let value):
 					if let index = model.index(where: { $0.id == id }) {
 						model[index].value = value
 					}
+                case .selectedChanged(let id, let selected):
+                    if let index = model.index(where: { $0.id == id }) {
+                        model[index].selected = selected
+                    }
 				case .delete(let id):
 					if let index = model.index(where: { $0.id == id }) {
 						model.remove(at: index)
@@ -54,26 +60,35 @@ extension ViewModel {
 struct CellInput {
     let plus: Observable<Void>
     let minus: Observable<Void>
+    let select: Observable<Void>
     let delete: Observable<Void>
 }
 
 struct CellViewModel {
     let label: Observable<String>
+    let selected: Observable<Bool>
+
+    let selectedChanged: Observable<Bool>
     let value: Observable<Int>
     let delete: Observable<Void>
 }
 
 extension CellViewModel {
-    init(_ input: CellInput, initialValue: Int) {
+    init(_ input: CellInput, initialValue: Model) {
         let add = input.plus.map { 1 } // plus adds one to the value
         let subtract = input.minus.map { -1 } // minus subtracts one
 
+        selectedChanged = input.select
+            .scan(initialValue.selected, accumulator: { val, _ in !val })
+        selected = selectedChanged
+            .startWith(initialValue.selected)
+
         value = Observable.merge(add, subtract)
-            .scan(initialValue, accumulator: +) // the logic is here
+            .scan(initialValue.value, accumulator: +) // the logic is here
 
-        label = value
-            .startWith(initialValue)
-            .map { "number is \($0)" } // create the string from the value
+        label = Observable.combineLatest(value, selectedChanged)
+            .startWith((initialValue.value, initialValue.selected))
+            .map { "number is \($0) | selected \($1)" } // create the string from the value
         delete = input.delete // delete is just a passthrough in this case
     }
 }