在下面的代码中，我试图构建一个锻炼计划生成器。有些方面仍然缺失，但不幸的是，我的状态不再起作用，可能位于ExerciseSetEntryView 中。当我预览此内容时，只会执行预览中的第一个操作。后续操作（例如在重量和持续时间之间切换）不起作用。
模型是 Objective-C 与 Core Data 交互。
import SwiftUI
import Foundation
struct ExercisePlanDayView: View {
@State var isEditing: Bool
@Binding var selectedDay: Int
@State var exerciseEntries: [ExerciseEntry] = []
@State var exerciseSetEntries: [ExerciseSetEntry] = []
let weekDays = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"]
var body: some View {
VStack {
HStack {
Text(weekDays[selectedDay])
Spacer()
Button(action: {
withAnimation {
isEditing.toggle()
}
//TODO: save stuff
}, label: {
Text(isEditing ? "Save" : "Edit")
})
.buttonStyle(.plain)
}
ForEach($exerciseEntries) { $exerciseEntry in
ExerciseEntryView(exerciseEntry: $exerciseEntry, exerciseSetEntries: $exerciseSetEntries, selectedDay: $selectedDay, isEditing: $isEditing)
}
Button(action: {
withAnimation {
//TODO: add a new exerciseEntry
}
}, label: {
Text("Add Exercise")
})
}
.padding(.horizontal, 5)
}
}
struct ExerciseEntryView: View {
@Binding var exerciseEntry: ExerciseEntry
@Binding var exerciseSetEntries: [ExerciseSetEntry]
@Binding var selectedDay: Int
@Binding var isEditing: Bool
var body: some View {
VStack (spacing: 5) {
HStack (spacing: 5) {
Text(exerciseEntry.exerciseName)
.padding(.horizontal, 10)
.fontWeight(.semibold)
.frame(width: 300, alignment: .leading)
.foregroundStyle(.base)
.background {
Rectangle()
.foregroundStyle(.greenEnd)
.cornerRadius(12)
.frame(height: 30)
}
if (isEditing) {
Button(action: {
withAnimation {
// TODO: remove the sets for this exercise
// TODO: remove Exercise
}
}, label: {
Image(systemName: "minus.circle.fill")
.foregroundStyle(.white, .red)
.frame(height: 30)
})
.buttonStyle(.plain)
}
Spacer()
}
ForEach($exerciseSetEntries.filter({ $0.exerciseID.wrappedValue == exerciseEntry.id.uuidString })) { $exerciseSetEntry in
ExerciseSetEntryView(exerciseSetEntry: $exerciseSetEntry, isEditing: $isEditing)
}
}
}
}
struct ExerciseSetEntryView: View {
@AppStorage("useMetric") var useMetric: Bool = false
@Binding var exerciseSetEntry: ExerciseSetEntry
@Binding var isEditing: Bool
var body: some View{
VStack {
if (isEditing) {
HStack (alignment: .top, spacing: 0) {
Button(action: {
}, label: {
Image(systemName: "minus.circle.fill")
.foregroundStyle(.white, .red)
})
.frame(height: 20)
HStack (alignment: .top, spacing: 0) {
VStack {
Picker("Select Activity Type", selection: $exerciseSetEntry.activityType) {
Text("Weight").tag("weight")
Text("Duration").tag("duration")
}
.pickerStyle(.segmented)
.frame(width: 140)
.padding(.leading, 5)
}
VStack {
if exerciseSetEntry.activityType == "weight" {
// Stepper for repetitions
Stepper(value: $exerciseSetEntry.repetitions, in: 1...500, step: 10) {
Text("\(exerciseSetEntry.repetitions) reps")
.frame(width: 90)
}
// Stepper for weight lifted
Stepper(value: $exerciseSetEntry.weightLifted, in: 1...500, step: 10) {
Text("\(exerciseSetEntry.weightLifted) \(useMetric ? "kg" : "lbs")")
.frame(width: 90)
}
} else if exerciseSetEntry.activityType == "duration" {
// Stepper for duration (in minutes)
Stepper(value: $exerciseSetEntry.duration, in: 1...180, step: 1) {
Text("\(exerciseSetEntry.duration / 60) min")
.frame(width: 90)
}
}
}
.frame(width: 180)
}
.background {
Rectangle()
.foregroundStyle(.clear)
.cornerRadius(12)
.frame(height: 30)
}
}
} else {
HStack (spacing: 0) {
if (isEditing) {
HStack {
if (exerciseSetEntry.repetitions != 0) {
Image(systemName: "repeat")
Text("\(exerciseSetEntry.repetitions) reps")
}
if (exerciseSetEntry.weightLifted != 0) {
Image(systemName: "scalemass.fill")
Text("\(exerciseSetEntry.repetitions) \(useMetric ? "kg" : "lbs")")
}
if (exerciseSetEntry.duration != 0) {
Text("\(exerciseSetEntry.duration / 60) minutes")
}
}
.padding(.horizontal, 10)
.frame(height: 30, alignment: .leading)
.background {
Rectangle()
.foregroundStyle(.orange)
.cornerRadius(12)
.frame(height: 30)
}
}
Button(action: {
}, label: {
Image(systemName: "minus.circle.fill")
.foregroundStyle(.white, .red)
})
.frame(height: 20)
.padding(.leading, 5)
Spacer()
}
}
}
}
}
struct ExercisePlanDayView_Previews: PreviewProvider {
static var previews: some View {
let uuid1 = UUID()
let uuid2 = UUID()
let uuid3 = UUID()
let exerciseEntries: [ExerciseEntry] = [
ExerciseEntry(id: uuid1, day: 1, exerciseOrder: 1, exerciseName: "Push-ups"),
ExerciseEntry(id: uuid2, day: 1, exerciseOrder: 2, exerciseName: "Sit-ups"),
ExerciseEntry(id: uuid3, day: 1, exerciseOrder: 3, exerciseName: "Squats"),
]
let exerciseSetEntries: [ExerciseSetEntry] = [
ExerciseSetEntry(id: UUID(), exerciseID: uuid1.uuidString, activityType: "weight", setOrder: 1, repetitions: 10, duration: 0, weightLifted: 210),
ExerciseSetEntry(id: UUID(), exerciseID: uuid1.uuidString, activityType: "weight", setOrder: 2, repetitions: 15, duration: 0, weightLifted: 150),
ExerciseSetEntry(id: UUID(), exerciseID: uuid2.uuidString, activityType: "duration", setOrder: 1, repetitions: 0, duration: 360, weightLifted: 0),
ExerciseSetEntry(id: UUID(), exerciseID: uuid3.uuidString, activityType: "weight", setOrder: 1, repetitions: 10, duration: 0, weightLifted: 210),
]
return ExercisePlanDayView(exerciseViewModel: ExerciseViewModel(), isEditing: true, selectedDay: .constant(1), exerciseEntries: exerciseEntries, exerciseSetEntries: exerciseSetEntries)
}
}
import Foundation
import CoreData
@objc(ExerciseEntry)
public class ExerciseEntry: NSManagedObject, Identifiable {
@NSManaged public var id: UUID
@NSManaged public var day: Int16
@NSManaged public var exerciseOrder: Int16
@NSManaged public var exerciseName: String
convenience init(
id: UUID,
day: Int16,
exerciseOrder: Int16,
exerciseName: String
) {
let entityName = "ExerciseEntry" // Set the entity name here
guard let entity = NSEntityDescription.entity(forEntityName: entityName, in: PersistenceController.shared.container.viewContext) else {
fatalError("Failed to initialize ExerciseEntry entity")
}
self.init(entity: entity, insertInto: PersistenceController.shared.container.viewContext)
self.id = id
self.day = day
self.exerciseOrder = exerciseOrder
self.exerciseName = exerciseName
}
}
@objc(ExerciseSetEntry)
public class ExerciseSetEntry: NSManagedObject, Identifiable {
@NSManaged public var id: UUID
@NSManaged public var exerciseID: String
@NSManaged public var activityType: String
@NSManaged public var setOrder: Int16
@NSManaged public var repetitions: Int16
@NSManaged public var duration: Int16
@NSManaged public var weightLifted: Int16
convenience init(
id: UUID,
exerciseID: String,
activityType: String,
setOrder: Int16,
repetitions: Int16,
duration: Int16,
weightLifted: Int16
) {
let entity = PersistenceController.shared.getExerciseSetEntry()
self.init(entity: entity, insertInto: nil)
self.id = id
self.exerciseID = exerciseID
self.activityType = activityType
self.setOrder = setOrder
self.repetitions = repetitions
self.duration = duration
self.weightLifted = weightLifted
}
}
我尝试从 ChatGPT 中反驳问题，对 ForEach 进行了自己的研究，研究了状态性等。我尝试了一些示例视图，但似乎没有一个真正解决了我的首要问题。
对于 SwiftUI 中的 CoreData，不要使用
@State@FetchRequest@ObservedObjectstruct ExercisePlanDayView: View {
@FetchRequest(
sortDescriptors: [NSSortDescriptor(keyPath: \ ExerciseEntry.timestamp, ascending: true)],
animation: .default)
private var exerciseEntries: FetchedResults<ExerciseEntry>
var body: some View {
...
ForEach(exerciseEntries) { exerciseEntry in
ExerciseEntryView(exerciseEntry: exerciseEntry)
struct ExerciseEntryView: View {
@ObservedObject var exerciseEntry: ExerciseEntry