🖖 Implement MVVM

using classes instead of structs in the model, and giving UnitVM
a function to update any of its SubjectVMs

Graduator/Graduator/MainView.swift

@@ -45,9 +45,14 @@ struct MainView: View {
                 
                 VStack(alignment: .leading) {
                     ForEach(unitsManagerVM.UnitsVM) { unitVM in
-                        NavigationLink(
+                        NavigationLink(destination: UnitView(
-                            destination: UnitView(unitVM: unitVM)) {
+                            unitVM: unitVM,
-                                UnitViewCell(unitVM: unitVM)
+                            unitsManagerVM: unitsManagerVM
+                        )) {
+                                UnitViewCell(
+                                    unitVM: unitVM,
+                                    unitsManagerVM: unitsManagerVM
+                                )
                         }
                     }
                 }
@@ -58,8 +63,13 @@ struct MainView: View {
 }
 
 struct MainView_Previews: PreviewProvider {
+    static var ManagerVMStub: UnitsManagerVM = UnitsManagerVM(
+        unitsManager: UnitsManager(
+            units: Stub.units
+        )
+    )
+
     static var previews: some View {
-        MainView(unitsManagerVM: UnitsManagerVM(unitsManager: UnitsManager(units: Stub.units)))
+        MainView(unitsManagerVM: ManagerVMStub)
     }
 }
-    

Graduator/Graduator/Model/UnitsManager.swift

@@ -11,10 +11,6 @@ struct UnitsManager {
     
     var units: [Unit]
     
-    init(units: [Unit]) {
-        self.units = units
-    }
-    
     func getTotalAverage() -> Double? {
         return getAverage(units: units)
     }
@@ -23,7 +19,7 @@ struct UnitsManager {
         return getAverage(units: units.filter { $0.isProfessional })
     }
     
-    private func getAverage(units: [Unit]) -> Double? {
+    func getAverage(units: [Unit]) -> Double? {
         var totalWeight = 0
         var weightedSum = 0.0
 

Graduator/Graduator/Stub.swift

@@ -97,23 +97,23 @@ struct Stub {
                 ),
                 Subject(
                     id: UUID(),
-                    name: "Économie",
+                    name: "Communication",
                     weight: 4,
-                    grade: 9.5/20.0,
+                    grade: 17.13/20.0,
                     isCalled: false
                 ),
                 Subject(
                     id: UUID(),
-                    name: "Gestion",
+                    name: "Économie",
-                    weight: 3,
+                    weight: 4,
                     grade: 9.5/20.0,
                     isCalled: false
                 ),
                 Subject(
                     id: UUID(),
-                    name: "Communication",
+                    name: "Gestion",
-                    weight: 4,
+                    weight: 3,
-                    grade: 17.13/20.0,
+                    grade: 9.5/20.0,
                     isCalled: false
                 ),
             ]
@@ -195,7 +195,7 @@ struct Stub {
                 ),
                 Subject(
                     id: UUID(),
-                    name: "MAUI",
+                    name: "Xamarin",
                     weight: 5,
                     isCalled: false
                 ),

Graduator/Graduator/View/Cells/SubjectViewCell.swift

@@ -9,6 +9,8 @@ import SwiftUI
 
 struct SubjectViewCell: View {
     @ObservedObject var subjectVM: SubjectVM
+    @ObservedObject var unitVM: UnitVM
+    @ObservedObject var unitsManagerVM: UnitsManagerVM
     
     //TODO also allow using the unitview's navigation bar item "Edit" (makes all subjects editable, and more)
     @State private var isEditable = false    
@@ -20,6 +22,8 @@ struct SubjectViewCell: View {
                     Button(action: {
                         isEditable = false
                         subjectVM.onEdited()
+                        unitVM.updateSubject(subjectVM)
+                        unitsManagerVM.updateUnit(unitVM)
                     }) {
                         Image(systemName: "checkmark.square")
                             .foregroundColor(.green)
@@ -107,7 +111,17 @@ struct SubjectViewCell: View {
 
 
 struct SubjectViewCell_Previews: PreviewProvider {
+    static var ManagerVMStub: UnitsManagerVM = UnitsManagerVM(
+        unitsManager: UnitsManager(
+            units: Stub.units
+        )
+    )
+    
     static var previews: some View {
-        SubjectViewCell(subjectVM: SubjectVM(subject: Stub.units[0].subjects[0]))
+        SubjectViewCell(
+            subjectVM: ManagerVMStub.UnitsVM[0].SubjectsVM[0],
+            unitVM: ManagerVMStub.UnitsVM[0],
+            unitsManagerVM: ManagerVMStub
+        )
     }
 }

Graduator/Graduator/View/Cells/UnitViewCell.swift

@@ -9,6 +9,7 @@ import SwiftUI
 
 struct UnitViewCell: View {
     @ObservedObject var unitVM: UnitVM
+    @ObservedObject var unitsManagerVM: UnitsManagerVM
 
     var body: some View {
         VStack {
@@ -48,7 +49,15 @@ struct UnitViewCell: View {
 }
 
 struct UnitViewCell_Previews: PreviewProvider {
+    static var ManagerVMStub: UnitsManagerVM = UnitsManagerVM(
+        unitsManager: UnitsManager(
+            units: Stub.units
+        )
+    )
     static var previews: some View {
-        UnitViewCell(unitVM: UnitVM(unit: Stub.units[0]))
+        UnitViewCell(
+            unitVM: UnitVM(unit: Stub.units[0]),
+            unitsManagerVM: ManagerVMStub
+        )
     }
 }

Graduator/Graduator/View/Components/NoGradesInfo.swift

@@ -15,3 +15,10 @@ struct NoGradesInfo: View {
         }
     }
 }
+
+
+struct NoGradesInfo_Previews: PreviewProvider {
+    static var previews: some View {
+        NoGradesInfo()
+    }
+}

Graduator/Graduator/View/Views/UnitView.swift

@@ -9,14 +9,21 @@ import SwiftUI
 
 struct UnitView: View {
     @ObservedObject var unitVM: UnitVM
+    @ObservedObject var unitsManagerVM: UnitsManagerVM
 
     var body: some View {
         VStack(alignment: .leading) {
-            Text("Unit title")
+            HStack {
+                Text("UE " + String(unitVM.model.code))
+                Text(unitVM.model.name)
+            }
             .font(.title)
             .padding()
             
-            UnitViewCell(unitVM: unitVM)
+            UnitViewCell(
+                unitVM: unitVM,
+                unitsManagerVM: unitsManagerVM
+            )
             
             Divider()
             
@@ -33,14 +40,18 @@ struct UnitView: View {
             .padding(.horizontal)
 
             ScrollView {
-                ForEach(unitVM.subjectVMs) { subjectVM in
+                ForEach(unitVM.SubjectsVM) { subjectVM in
-                    SubjectViewCell(subjectVM: subjectVM)
+                    SubjectViewCell(
+                        subjectVM: subjectVM,
+                        unitVM: unitVM,
+                        unitsManagerVM: unitsManagerVM
+                    )
                 }
             }
             .navigationBarItems(trailing: Button(action: {
                 // TODO Add action for button. Make editable
-                // * (LATER) unit weight
+                // * (LATER, in UnitViewCell) unit weight
-                // * (LATER) unit description
+                // * (LATER, in UnitViewCell) unit description
                 // * subjects
                 //   * make all fields editable (=> just toggle isEditable is the SubjectCellViews?)
                 //   * create new subject (creation screen with simple form for name, weight, code, isCalled. Of course, will need to deal with adding it to the unitVM, updating the unitVM, and updating the unitsmanagerVM with the new unitVM. Check the result to make sure that the model does get updated by the VM in the end)
@@ -53,7 +64,17 @@ struct UnitView: View {
 }
 
 struct UnitView_Previews: PreviewProvider {
+    
+    static var ManagerVMStub: UnitsManagerVM = UnitsManagerVM(
+        unitsManager: UnitsManager(
+            units: Stub.units
+        )
+    )
+    
     static var previews: some View {
-        UnitView(unitVM: UnitVM(unit: Stub.units[0]))
+        UnitView(
+            unitVM: ManagerVMStub.UnitsVM[0],
+            unitsManagerVM: ManagerVMStub
+        )
     }
 }

Graduator/Graduator/ViewModel/SubjectVM.swift

@@ -16,14 +16,6 @@ extension Subject {
         var isCalled: Bool
     }
     
-    init(subjectData: Subject.Data) {
-        self.id = subjectData.id
-        self.name = subjectData.name
-        self.weight = subjectData.weight
-        self.grade = subjectData.grade
-        self.isCalled = subjectData.isCalled
-    }
-    
     var data: Data {
         Data(
             id: self.id,
@@ -52,7 +44,6 @@ extension Subject {
 class SubjectVM : ObservableObject, Identifiable {
     private var original: Subject
     var id: UUID { original.id }
-    weak var unitVM: UnitVM?
     @Published var model: Subject.Data
     @Published var isEdited: Bool = false
     
@@ -61,11 +52,6 @@ class SubjectVM : ObservableObject, Identifiable {
         model = original.data
     }
     
-    init(subjectData: Subject.Data) {
-        self.original = Subject(subjectData: subjectData)
-        self.model = subjectData
-    }
-    
     convenience init() {
         self.init(subject: Subject(
             id: UUID(),
@@ -82,14 +68,9 @@ class SubjectVM : ObservableObject, Identifiable {
     
     func onEdited(isCancelled: Bool = false) {
         if(!isCancelled && original.gradeIsValid(model.grade)){
-            if (isEdited) {
             original.update(from: model)
-                unitVM?.updateSubjects()
-            }
         }
-        else {
         model = original.data
-        }
         isEdited = false
     }
 }

Graduator/Graduator/ViewModel/UnitVM.swift

@@ -14,7 +14,7 @@ extension Unit {
         var weight: Int
         var isProfessional: Bool
         var code: Int
-        public var subjects: [Subject.Data] = []
+        var subjects: [Subject.Data] = []
     }
     
     var data: Data {
@@ -51,15 +51,15 @@ class UnitVM : ObservableObject, Identifiable {
     var id: UUID { original.id }
     @Published var model: Unit.Data
     @Published var isEdited: Bool = false
-    @Published var subjectVMs: [SubjectVM]
+    
+    private var subjectsVM: [SubjectVM]
+    
+    public var SubjectsVM: [SubjectVM] { subjectsVM }
     
     init(unit: Unit) {
         original = unit
         model = original.data
-        subjectVMs = unit.subjects.map { SubjectVM(subject: $0) }
+        subjectsVM = unit.subjects.map { SubjectVM(subject: $0) }
-        for subjectVM in subjectVMs {
-            subjectVM.unitVM = self
-        }
     }
     
     convenience init() {
@@ -80,20 +80,16 @@ class UnitVM : ObservableObject, Identifiable {
     
     func onEdited(isCancelled: Bool = false) {
         if(!isCancelled){
-            if (isEdited) {
             original.update(from: model)
-                // TODO unitsManagerVM?.updateUnits()
         }
-        }
-        else {
         model = original.data
-        }
         isEdited = false
     }
     
-    func updateSubjects() {
+    func updateSubject(_ subjectVM: SubjectVM) {
-        // FIXME neither instruction seems to update the model. At least the unitViewCell wtill displays the old average after we update a grade inside
+        guard let index = subjectsVM.firstIndex(where: { $0.id == subjectVM.id }) else { return }
-        objectWillChange.send()
+        let updatedSubject = subjectsVM[index].model
+        original.subjects[index].update(from: updatedSubject)
         model = original.data
     }
     
@@ -102,6 +98,6 @@ class UnitVM : ObservableObject, Identifiable {
     }
 
     var IsCalled: Bool {
-        return model.subjects.allSatisfy { $0.isCalled }
+        return original.subjects.allSatisfy { $0.isCalled }
     }
 }

Graduator/Graduator/ViewModel/UnitsManagerVM.swift

@@ -49,32 +49,23 @@ class UnitsManagerVM : ObservableObject {
 
     private var unitsVM: [UnitVM]
     
-    public var UnitsVM: [UnitVM] {
+    public var UnitsVM: [UnitVM] { unitsVM }
-        unitsVM
-    }
     
     init(unitsManager: UnitsManager) {
         original = unitsManager
         model = original.data
-        unitsVM = unitsManager.units.map {
+        unitsVM = unitsManager.units.map { UnitVM(unit: $0) }
-            UnitVM(unit: $0)
-        }
     }
     
     convenience init() {
         self.init(unitsManager: UnitsManager(units: []))
     }
     
-    func onEditing() {
+    func updateUnit(_ unitVM: UnitVM) {
+        guard let index = unitsVM.firstIndex(where: { $0.id == unitVM.id }) else { return }
+        let updatedUnit = unitsVM[index].model
+        original.units[index].update(from: updatedUnit)
         model = original.data
-        isEdited = true
-    }
-    
-    func onEdited(isCancelled: Bool = false) {
-        if(!isCancelled && isEdited){
-            original.update(from: model)
-        }
-        isEdited = false
     }
     
     var TotalAverage: Double? {