iOS15+Firestore点赞按钮实现取消点赞（-1）功能求助

此前已解决点赞数正常更新的问题，但当前存在新问题：点击点赞按钮时点赞数会+1，但再次点击仍持续+1，需要实现再次点击时点赞数-1的功能。尝试使用.disabled(islike)会直接禁止再次点击按钮，使用Firebase Firestore、iOS15，求实现方案。

代码实现 #

CellLike.swift #

import SwiftUI
import Firebase
import FirebaseFirestoreSwift

struct CellLike: View {
    
    @Binding var isLike: Bool
    @State private var animate = false
    private let animationDuration: Double = 0.1
    private var animationScale: CGFloat {
        isLike ? 0.7 : 1.3
    }
    @ObservedObject var data = getData()
    let timer = Timer.publish(every: 1, on: .current, in: .common).autoconnect()
    
    var body: some View {
        
        VStack {
            
            if self.data.data != nil {
                
                HStack {
                    Button {
                        self.animate = true
                        /// Add +1 Like
                        Firestore.firestore().collection("Like").document("Option").updateData(["ss" : FieldValue.increment(1.0) ])
                        DispatchQueue.main.asyncAfter(deadline: .now() + self.animationDuration) {
                            self.animate = false
                            self.isLike.toggle()
                        }
                    } label: {
                        Image(systemName: isLike ? "heart.fill" : "heart")
                            .resizable()
                            .aspectRatio(contentMode: .fit)
                            .frame(width: 60)
                            .foregroundColor(isLike ? .red : .gray)
                    }
                    .scaleEffect(animate ? animationScale : 1)
                    .animation(.easeIn(duration: animationDuration), value: animate)
//                    .disabled(isLike)
                    /// Number like
                    Text("\(self.data.data.like)")
                        .font(.system(size: 40))
                        .fontWeight(.black)
                        .onReceive(timer) { update in
                            self.data.updateData()
                        }
                }
            }
        }
    }
}

DataManager.swift #

import Foundation
import Firebase

struct Datas {
    var like: Int
}

class getData: ObservableObject {
    @Published var data: Datas!
    
    init() {
        updateData()
    }
    
    func updateData() {
        let db = Firestore.firestore()
        
        db.collection("Like").document("Option").getDocument { (snap, err) in
            
            if err != nil {
                print((err?.localizedDescription)!)
                return
            }
            
            let like = snap?.get("ss") as! Int
            
            DispatchQueue.main.async {
                self.data = Datas(like: like)
            }
        }
    }
}

LikeButtonView.swift #

struct LikeButtonView: View {
    @AppStorage("isLike") private var isLike = false
    var body: some View {
        CellLike(isLike: $isLike)
    }
}

相关截图 #

• Firestore数据库集合：
  

• 当前点击效果：
  

内容的提问来源于stack exchange，提问作者Denis