tmp illustration for #61

Example/DSWaveformImageExample-iOS/SwiftUIExample/SwiftUIExampleView.swift

@@ -54,6 +54,9 @@ struct SwiftUIExampleView: View {
         .padding(.vertical, 20)
     }
 
+    @State var progress: Double = 0
+    let timer = Timer.publish(every: 0.2, on: .main, in: .common).autoconnect()
+
     @available(iOS 15.0, *)
     @ViewBuilder
     private var recordingExample: some View {
@@ -85,11 +88,30 @@ struct SwiftUIExampleView: View {
         .padding()
 
         if let audioURL {
-            WaveformView(
-                audioURL: audioURL,
-                configuration: configuration,
-                renderer: CircularWaveformRenderer(kind: .ring(0.7))
+            let configuration: Waveform.Configuration = .init(
+                style: .striped(.init(color: .gray, width: 1, spacing: 2))
             )
+
+            GeometryReader { proxy in
+                ZStack(alignment: .leading) {
+                    // Static waveform view, showing the whole file
+                    WaveformView(audioURL: audioURL, configuration: configuration)
+                        .frame(width: proxy.size.width)
+
+                    // Animated progress indicator, masked to the same waveformView, to show the progress
+                    let width = min(progress * proxy.size.width, proxy.size.width)
+                    Rectangle()
+                        .frame(width: width)
+                        .foregroundColor(.blue)
+                        .mask(alignment: .leading) {
+                        WaveformView(audioURL: audioURL, configuration: configuration)
+                            .frame(width: proxy.size.width)
+                    }
+                        .animation(.linear, value: progress)
+                }
+            }.onReceive(timer) { _ in
+                self.progress = (self.progress + 0.02).truncatingRemainder(dividingBy: 1)
+            }
         }
 
         VStack {