Add conditional onСhange.

Author: bullinnyc

.github/workflows/build-and-test.yml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        xcode: ['14.3']
+        xcode: ['15.0.1']
         macos: ['macos-13']
         scheme: ['CachedAsyncImage']
         command: ['test']

Examples/ContentView.swift

@@ -85,7 +85,7 @@ struct ContentView: View {
                                     )
                             )
                             .clipped()
-                            .cornerRadius(20)
+                            .clipShape(RoundedRectangle(cornerRadius: 20))
                             .padding([.leading, .trailing], Self.paddingStandart)
                         }
                     }

Sources/CachedAsyncImage/Extensions/Extension + View.swift

@@ -14,12 +14,12 @@ extension View {
     /// Used, e.g. to use the if #available statement.
     ///
     ///     .conditional { view in
-    ///         if #available(iOS 16.0, *) {
+    ///         if #available(iOS 15.0, macOS 12.0, *) {
     ///             view
-    ///                 .tint(cursorColor)
+    ///                 .foregroundStyle(.red)
     ///         } else {
     ///             view
-    ///                 .accentColor(cursorColor)
+    ///                 .foregroundColor(.red)
     ///         }
     ///
     /// - Parameter transform: The transform to apply to the source `View`.

Sources/CachedAsyncImage/Modifiers/OnChange.swift

@@ -0,0 +1,57 @@
+//
+//  OnChange.swift
+//  CachedAsyncImage
+//
+//  Created by Dmitry Kononchuk on 23.11.2023.
+//  Copyright © 2023 Dmitry Kononchuk. All rights reserved.
+//
+
+import SwiftUI
+
+struct OnChange<Value>: ViewModifier where Value: Equatable {
+    // MARK: - Public Properties
+    
+    let value: Value
+    let isInitial: Bool
+    let action: (_ oldValue: Value?, _ newValue: Value) -> Void
+    
+    // MARK: - Body Method
+    
+    func body(content: Content) -> some View {
+        if #available(iOS 17.0, macOS 14.0, *) {
+            content
+                .onChange(of: value, initial: isInitial) { oldValue, newValue in
+                    action(oldValue, newValue)
+                }
+        } else {
+            content
+                .onChange(of: value) { newValue in
+                    action(nil, newValue)
+                }
+        }
+    }
+}
+
+// MARK: - Ext. View
+
+extension View {
+    /// Method overloading – onChange(of:initial:_:).
+    /// Adds a modifier for this view that fires an action when a specific value changes.
+    ///
+    /// - Parameters:
+    ///   - value: The value to check against when determining whether to run the closure.
+    ///   - isInitial: Whether the action should be run when this view initially appears.
+    ///   - action: A closure to run when the value changes.
+    ///   - oldValue: The old value that failed the comparisoncheck
+    ///   (or the initial value when requested).
+    ///   - newValue: The new value that failed the comparison check.
+    ///
+    /// - Returns: A view that fires an action when the specified value changes.
+    func onChange<Value>(
+        of value: Value,
+        isInitial: Bool = false,
+        action: @escaping (_ oldValue: Value?, _ newValue: Value) -> Void
+    ) -> some View where Value: Equatable {
+        modifier(OnChange(value: value, isInitial: isInitial, action: action))
+    }
+}

Sources/CachedAsyncImage/Views/CachedAsyncImage.swift

@@ -32,7 +32,9 @@ public struct CachedAsyncImage: View {
                 errorOrPlaceholder
             }
         }
-        .onChange(of: url, perform: { imageLoader.fetchImage(from: $0) })
+        .onChange(of: url) { _, newValue in
+            imageLoader.fetchImage(from: newValue)
+        }
         .onAppear {
             imageLoader.fetchImage(from: url)
         }
@@ -57,8 +59,8 @@ public struct CachedAsyncImage: View {
         self.image = image
         self.error = error
 
-        self.placeholder = nil
-        self.placeholderWithProgress = nil
+        placeholder = nil
+        placeholderWithProgress = nil
     }
 
     /// - Parameters:
@@ -81,7 +83,7 @@ public struct CachedAsyncImage: View {
         self.image = image
         self.error = error
 
-        self.placeholderWithProgress = nil
+        placeholderWithProgress = nil
     }
 
     /// - Parameters:
@@ -100,11 +102,11 @@ public struct CachedAsyncImage: View {
         )
 
         self.url = url
-        self.placeholderWithProgress = placeholder
+        self.placeholder = nil
         self.image = image
         self.error = error
 
-        self.placeholder = nil
+        placeholderWithProgress = placeholder
     }
 }
 
@@ -173,23 +175,13 @@ struct CachedAsyncImage_Previews: PreviewProvider {
                 .font(.footnote)
                 .multilineTextAlignment(.center)
                 .conditional { view in
-                    #if os(iOS)
-                    if #available(iOS 15.0, *) {
-                        view
-                            .foregroundStyle(.red)
-                    } else {
-                        view
-                            .foregroundColor(.red)
-                    }
-                    #elseif os(macOS)
-                    if #available(macOS 12.0, *) {
+                    if #available(iOS 15.0, macOS 12.0, *) {
                         view
                             .foregroundStyle(.red)
                     } else {
                         view
                             .foregroundColor(.red)
                     }
-                    #endif
                 }
             }
             .padding()