fix onChange of deprecation warnings for visionOS 1.0

Author: dmrschmidt

Sources/DSWaveformImageViews/SwiftUI/VersionMigrations.swift

@@ -0,0 +1,46 @@
+import SwiftUI
+
+// workaround for crashes in iOS 15 when using #available in ViewBuilders
+// see https://developer.apple.com/forums/thread/650818
+// not sure if this is still relevant, but keeping it due to its obscurity when it occurs
+// and because I cannot verify that it does not happen anymore due to lack of devices
+public struct LazyContent<Content: View>: View {
+    let content: () -> Content
+
+    public init(@ViewBuilder content: @escaping () -> Content) {
+        self.content = content
+    }
+
+    public var body: some View {
+        content()
+    }
+}
+
+// This is here to support visionOS / iOS 17 and remove the deprecation warning relating about the usage of
+//   @available(visionOS, deprecated: 1.0, message: "Use `onChange` with a two or zero parameter action closure instead.")
+//   @inlinable public func onChange<V>(of value: V, perform action: @escaping (_ newValue: V) -> Void) -> some View where V : Equatable
+public struct OnChange<V: Equatable>: ViewModifier {
+    private var value: V
+    private var action: (_ newValue: V) -> Void
+
+    public init(of value: V, action: @escaping (_ newValue: V) -> Void) {
+        self.value = value
+        self.action = action
+    }
+
+    public func body(content: Content) -> some View {
+        if #available(iOS 17, visionOS 1.0, *) {
+            LazyContent {
+                content
+                    .onChange(of: value) { _, newValue in
+                        action(newValue)
+                    }
+            }
+        } else {
+            content
+                .onChange(of: value) { newValue in
+                    action(newValue)
+                }
+        }
+    }
+}

Sources/DSWaveformImageViews/SwiftUI/WaveformLiveCanvas.swift

@@ -37,9 +37,9 @@ public struct WaveformLiveCanvas: View {
         .onAppear {
             waveformDrawer.shouldDrawSilencePadding = shouldDrawSilencePadding
         }
-        .onChange(of: shouldDrawSilencePadding) { newValue in
+        .modifier(OnChange(of: shouldDrawSilencePadding, action: { newValue in
             waveformDrawer.shouldDrawSilencePadding = newValue
-        }
+        }))
     }
 }
 

Sources/DSWaveformImageViews/SwiftUI/WaveformView.swift

@@ -43,9 +43,9 @@ public struct WaveformView<Content: View>: View {
                     guard samples.isEmpty else { return }
                     update(size: geometry.size, url: audioURL, configuration: configuration)
                 }
-                .onChange(of: geometry.size) { update(size: $0, url: audioURL, configuration: configuration) }
-                .onChange(of: audioURL) { update(size: geometry.size, url: $0, configuration: configuration) }
-                .onChange(of: configuration) { update(size: geometry.size, url: audioURL, configuration: $0) }
+                .modifier(OnChange(of: geometry.size, action: { newValue in update(size: newValue, url: audioURL, configuration: configuration) }))
+                .modifier(OnChange(of: audioURL, action: { newValue in update(size: geometry.size, url: audioURL, configuration: configuration) }))
+                .modifier(OnChange(of: configuration, action: { newValue in update(size: geometry.size, url: audioURL, configuration: newValue) }))
         }
     }