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comparison Simoleon/Helpers/FavoriteButton.swift @ 53:b0bce2c8e4a9

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Refactor UK spelling to US
author Dennis Concepción Martín <dennisconcepcionmartin@gmail.com>
date Tue, 27 Jul 2021 09:44:51 +0100
parents Simoleon/Helpers/FavouriteButton.swift@7a6a7c677851
children 529feb1fc8d5 501ea028ea5e
comparison
equal deleted inserted replaced
52:3fa127885e60 53:b0bce2c8e4a9
1 //
2 // FavoriteButton.swift
3 // Simoleon
4 //
5 // Created by Dennis Concepción Martín on 19/07/2021.
6 //
7
8 import SwiftUI
9
10 struct FavoriteButton: View {
11 var currencyPair: String
12
13 @Environment(\.managedObjectContext) private var viewContext
14 @FetchRequest(sortDescriptors: []) private var favorite: FetchedResults<Favorite>
15
16 @State private var starSymbol = "star"
17
18 var body: some View {
19 let favoriteCurrencyPairs = favorite.map { $0.currencyPair }
20 Button(action: { favoriteAction(favoriteCurrencyPairs) }) {
21 RoundedRectangle(cornerRadius: 15)
22 .foregroundColor(Color(.secondarySystemBackground))
23 .frame(width: 60, height: 60)
24 .overlay(
25 Image(systemName: generateStar(favoriteCurrencyPairs))
26 .font(.system(size: 28))
27 .foregroundColor(Color(.systemYellow))
28 )
29 }
30 }
31
32 /*
33 If currency pair is favorite:
34 * Button action is to remove from favorites
35 else:
36 * Button action is to add to favorites
37 */
38 private func favoriteAction(_ favoriteCurrencyPairs: [String]) {
39 if favoriteCurrencyPairs.contains(currencyPair) {
40 removeFromFavorites()
41 } else {
42 addToFavorites()
43 }
44
45 simpleSuccess()
46 }
47
48 /*
49 if currency pair is favorite:
50 * Return "star.fill" symbol
51 else:
52 * Return "star"
53 */
54 private func generateStar(_ favoriteCurrencyPairs: [String]) -> String {
55 if favoriteCurrencyPairs.contains(currencyPair) {
56 return "star.fill"
57 } else {
58 return "star"
59 }
60 }
61
62 /*
63 * Get first favorite core data object that matches the specified currency pair
64 * Delete it
65 */
66 private func removeFromFavorites() {
67 withAnimation {
68 let favoriteObject = favorite.first(where: { $0.currencyPair == currencyPair })
69 viewContext.delete(favoriteObject ?? Favorite())
70
71 do {
72 try viewContext.save()
73 } catch {
74 let nsError = error as NSError
75 fatalError("Unresolved error \(nsError), \(nsError.userInfo)")
76 }
77 }
78 }
79
80 /*
81 * Create a favorite core data object
82 * Save it
83 */
84 private func addToFavorites() {
85 withAnimation {
86 let favorite = Favorite(context: viewContext)
87 favorite.currencyPair = currencyPair
88
89 do {
90 try viewContext.save()
91 } catch {
92 let nsError = error as NSError
93 fatalError("Unresolved error \(nsError), \(nsError.userInfo)")
94 }
95 }
96 }
97 }
98
99 struct FavoriteButton_Previews: PreviewProvider {
100 static var previews: some View {
101 FavoriteButton(currencyPair: "USD/GBP")
102 }
103 }