如何在自定义TableViewCell添加收藏按钮并保存至UserDefaults实现收藏列表？

Got it, let's break this down into actionable steps to get your favorite button and filter working properly:

First, add a favorite button to your custom cell (either via Storyboard/XIB or programmatically). Here's the updated cell code with button handling:

import UIKit

class ErgWorkoutCell: UITableViewCell {
    @IBOutlet weak var ergWorkoutTitle: UILabel!
    @IBOutlet weak var favoriteButton: UIButton!
    
    // Closure to pass tap events back to the view controller
    var favoriteTapped: ((_ isFavorite: Bool) -> Void)?
    
    // Track if the current workout is favorited
    private var isFavorited = false
    
    override func awakeFromNib() {
        super.awakeFromNib()
        setupFavoriteButton()
    }
    
    private func setupFavoriteButton() {
        // Set initial button image (adjust the image names to match your assets)
        favoriteButton.setImage(UIImage(systemName: "star"), for: .normal)
        favoriteButton.setImage(UIImage(systemName: "star.fill"), for: .selected)
    }
    
    // Call this from the VC to set the button state
    func configure(isFavorited: Bool) {
        self.isFavorited = isFavorited
        favoriteButton.isSelected = isFavorited
    }
    
    @IBAction func favoriteButtonTapped(_ sender: UIButton) {
        isFavorited.toggle()
        sender.isSelected = isFavorited
        favoriteTapped?(isFavorited)
    }
}

Don't forget to connect the favoriteButton outlet and its IBAction in your Storyboard/XIB!

To keep your code clean, create a simple helper to manage saving/retrieving favorite workout IDs. First, make sure your workoutList model has a unique identifier (like id: String or id: Int — using titles can cause conflicts, so a unique ID is better):

// Create a helper struct to handle UserDefaults operations
struct FavoriteManager {
    private static let favoritesKey = "ErgWorkoutFavorites"
    
    static func getFavoriteWorkoutIDs() -> Set<String> {
        return Set(UserDefaults.standard.stringArray(forKey: favoritesKey) ?? [])
    }
    
    static func toggleFavorite(workoutID: String) {
        var favorites = getFavoriteWorkoutIDs()
        if favorites.contains(workoutID) {
            favorites.remove(workoutID)
        } else {
            favorites.insert(workoutID)
        }
        UserDefaults.standard.set(Array(favorites), forKey: favoritesKey)
    }
    
    static func isWorkoutFavorited(workoutID: String) -> Bool {
        return getFavoriteWorkoutIDs().contains(workoutID)
    }
}

Now modify your view controller to handle the favorite button taps and filter for favorites:

First, Update cellForRowAt #

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let selectedGroup = selectedWorkoutGroup(libraryFilter: libraryFilter, jsonErgWorkouts: jsonErgWorkouts, workoutGroupBox: workoutGroupBox)
    let cell = tableView.dequeueReusableCell(withIdentifier: "ergWorkoutCell") as! ErgWorkoutCell
    
    let workout = selectedGroup[indexPath.row]
    cell.ergWorkoutTitle.text = workout.title
    
    // Configure favorite button state
    let isFavorited = FavoriteManager.isWorkoutFavorited(workoutID: workout.id) // Replace `workout.id` with your actual unique identifier
    cell.configure(isFavorited: isFavorited)
    
    // Handle favorite button tap
    cell.favoriteTapped = { [weak self] isFavorited in
        FavoriteManager.toggleFavorite(workoutID: workout.id)
        // If we're on the Favorites tab, refresh the table to remove the workout if needed
        if self?.libraryFilter == 3 {
            tableView.reloadData()
        }
    }
    
    return cell
}

Then, Fix the selectedWorkoutGroup Method #

Update the libraryFilter == 3 case to filter for favorited workouts:

func selectedWorkoutGroup(libraryFilter: Int, jsonErgWorkouts:[workoutList], workoutGroupBox: UITextField) -> [workoutList] {
    var selectedGroup = [workoutList]()
    let favoriteIDs = FavoriteManager.getFavoriteWorkoutIDs()
    
    switch libraryFilter {
    case 0:
        // Segmented Control #1 (Plan)
        selectedGroup = jsonErgWorkouts.filter { $0.group == workoutGroupBox.text }
    case 1:
        // Add your Tag filtering logic here
        selectedGroup = jsonErgWorkouts.filter { /* Your tag condition */ }
    case 2:
        // Add your Duration filtering logic here
        selectedGroup = jsonErgWorkouts.filter { /* Your duration condition */ }
    case 3:
        // Filter for favorited workouts
        selectedGroup = jsonErgWorkouts.filter { favoriteIDs.contains($0.id) } // Again, use your workout's unique ID
    default:
        selectedGroup = jsonErgWorkouts
    }
    return selectedGroup
}

Make sure your segmented control's value changed event triggers a table reload. Add this action to your segmented control (connect it in Storyboard or add programmatically):

@IBAction func libraryFilterChanged(_ sender: UISegmentedControl) {
    libraryFilter = sender.selectedSegmentIndex
    tableView.reloadData()
}

Quick Notes: #

• Replace workout.id with the actual unique identifier from your workoutList model (if you don't have one, consider adding a uuid property to each workout in your JSON or model).
• Adjust the favorite button images (the SF Symbols "star" and "star.fill" are used here, but you can use custom assets if needed).
• UserDefaults is perfect for small datasets like favorites, but if you expect a large number of favorites, consider using Core Data instead.

内容的提问来源于stack exchange，提问作者app4g