I'm using Swift UI . I'm using async and await to handle the concurrency. I am trying to display list of product record .I have 30 record into json here is the json link https://dummyjson.com/products. and I got the 30 record when I debug it but when I run the app , It only displaying one record only . I am wondering where is mistake or changes , I need to make .
Here is my model ..
import Foundation
// MARK: - Welcome
struct ProductData: Codable, Hashable {
let products: [Product]
}
// MARK: - Product
struct Product: Codable, Hashable {
let id: Int
let title, description: String
let price: Int
let discountPercentage, rating: Double
let stock: Int
let brand, category: String
let thumbnail: String
let images: [String]
}
Here is my view model code ..
@MainActor
final class ProductListViewModel {
@Published private(set) var productLists: [ProductData] = []
@Published private(set) var customError: NetworkError?
@Published private(set) var refreshing = true
@Published var isErrorOccured = false
private let repository: ProductRepository
init(repository: ProductRepository) {
self.repository = repository
}
}
extension ProductListViewModel: ProductListViewModelAction {
func getProductList(urlStr: String) async {
refreshing = true
guard let url = URL(string: urlStr) else {
self.customError = NetworkError.invalidURL
refreshing = false
isErrorOccured = false
return
}
do {
let lists = try await repository.getList(for: url)
refreshing = false
isErrorOccured = false
productLists = [lists]
} catch {
refreshing = false
isErrorOccured = true
customError = error as? NetworkError
}
}
}
Here is my view ..
import SwiftUI
struct ProductListView: View {
@StateObject var viewModel = ProductListViewModel(repository: ProductRepositoryImplementation(networkManager: NetworkManager()))
var body: some View {
NavigationStack {
VStack {
if viewModel.customError != nil && !viewModel.refreshing {
alertView()
} else {
if viewModel.refreshing {
progressView()
}
if viewModel.productLists.count > 0 && !viewModel.refreshing {
List(viewModel.productLists, id: \.self) { product in
ProductListViewCell(productData: product)
} .listStyle(.grouped)
}
}
}
.toolbar {
ToolbarItem(placement: .navigationBarTrailing) {
getToolBarView()
}
}
.navigationTitle(Text("Product List"))
}.task{
await getDataFromAPI()
}
.refreshable {
await getDataFromAPI()
}
}
func getDataFromAPI() async {
await viewModel.getProductList(urlStr: NetworkURL.productUrl)
}
@ViewBuilder
func getToolBarView() -> some View {
Button {
Task{
await getDataFromAPI()
}
} label: {
HStack {
Image(systemName: "arrow.clockwise")
.padding(.all, 10.0)
}.fixedSize()
}
.cornerRadius(5.0)
}
@ViewBuilder
func progressView() -> some View {
VStack{
RoundedRectangle(cornerRadius: 15)
.fill(.white)
.frame(height: 180)
.overlay {
VStack {
ProgressView().padding(50)
Text("Please Wait Message").font(.headline)
}
}
}
}
@ViewBuilder
func alertView() -> some View {
Text("").alert(isPresented: $viewModel.isErrorOccured) {
Alert(title: Text("General_Error"), message: Text(viewModel.customError?.localizedDescription ?? ""),dismissButton: .default(Text("Okay")))
}
}
}
Here is my cell view ..
import SwiftUI
struct ProductListViewCell: View {
let productData: ProductData
var body: some View {
HStack {
if let url = URL(string: productData.products.first?.thumbnail ?? ""){
ProductAsyncImageView(url: url)
.frame(width: 150, height: 150)
.mask(RoundedRectangle(cornerRadius: 16))
}
VStack(alignment: .leading,spacing: 5){
Text("Product Name: " + (productData.products.first?.title ?? ""))
.frame(maxWidth: .infinity, alignment: .leading)
.font(.headline)
Text("Product Description: " + (productData.products.first?.description ?? ""))
.frame(maxWidth: .infinity, alignment: .leading)
Text("Product Price: " + String(productData.products.first?.price ?? 0))
.frame(maxWidth: .infinity, alignment: .leading)
.font(.subheadline)
}
}
}
}
Here is the result in the debug ..
Here is the screenshot..Only one record is displayed.
The productLists = [lists]
creates an array with one item in it. Now, that ProductData
might have thirty products in it, but ProductListViewCell
then creates a cell for only the first product in that ProductData
. Thus, only one item will be shown.
I would suggest product list view model should probably just take an array of products:
final class ProductListViewModel: ObservableObject {
@Published private(set) var products: [Product] = [] // an array of products
…
}
extension ProductListViewModel {
func getProductList(urlStr: String) async {
refreshing = true
guard let url = URL(string: urlStr) else { … }
do {
let productList = try await repository.getList(for: url)
refreshing = false
isErrorOccured = false
products = productList.products // get the list of products
} catch {
…
}
}
}
The then the ProductListView
would show this array of Product
:
struct ProductListView: View {
@StateObject var viewModel = …
var body: some View {
NavigationStack {
VStack {
…
if viewModel.products.count > 0 && !viewModel.refreshing {
List(viewModel.products, id: \.self) { product in
ProductListViewCell(product: product)
} .listStyle(.grouped)
}
}
}
The cell then just takes a Product
:
struct ProductListViewCell: View {
let product: Product
var body: some View {
HStack {
if let url = URL(string: product.thumbnail) { … }
VStack(alignment: .leading, spacing: 5) {
Text("Product Name: \(product.title)")
.frame(maxWidth: .infinity, alignment: .leading)
.font(.headline)
Text("Product Description: \(product.description)")
.frame(maxWidth: .infinity, alignment: .leading)
Text("Product Price: \(product.price)")
.frame(maxWidth: .infinity, alignment: .leading)
.font(.subheadline)
}
}
}
}
Yielding:
Now, there are lots of ways of skinning the cat: You can use your ProductData
if you want. But the key take-home message is that ProductListViewCell
is for showing a single Product
so it does not make sense to give it a whole ProductData
and only access the first
product in that array of 30 products contained within the ProductData
.