Merge pull request #3 from miquido/feature/detected_image_tapping

iOS - handle tapping on detected image

Author: PiotrMitkowski

example/lib/main.dart

@@ -32,6 +32,17 @@ class _MyAppState extends State<MyApp> {
     });
   }
 
+  void _onDetectedImageTapped(BuildContext context, String? imageName) {
+    if (imageName != null) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text('Tapped on image: $imageName'),
+          duration: const Duration(milliseconds: 1500),
+        ),
+      );
+    }
+  }
+
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
@@ -46,6 +57,7 @@ class _MyAppState extends State<MyApp> {
                 ARQuidoView(
                   referenceImageNames: const ['applandroid'],
                   onImageDetected: (imageName) => _onImageDetected(context, imageName),
+                  onDetectedImageTapped: (imageName) => _onDetectedImageTapped(context, imageName),
                 ),
               ],
             );

ios/Classes/ARImageScannerView/ARQuidoViewController.swift

@@ -8,6 +8,7 @@ protocol ImageRecognitionDelegate: AnyObject {
     func onRecognitionPaused()
     func onRecognitionResumed()
     func onDetect(imageKey: String)
+    func onDetectedImageTapped(imageKey: String)
 }
 
 class ARQuidoViewController: UIViewController {
@@ -47,6 +48,8 @@ class ARQuidoViewController: UIViewController {
         sceneView = ARSCNView(frame: CGRect.zero)
         sceneView.delegate = self
         sceneView.session.delegate = self
+        let tapGesture = UITapGestureRecognizer(target: self, action: #selector(handleTap(_:)))
+        sceneView.addGestureRecognizer(tapGesture)
         view = sceneView
     }
 
@@ -62,6 +65,16 @@ class ARQuidoViewController: UIViewController {
         onRecognitionPaused()
     }
 
+    @objc
+    func handleTap(_ gestureRecognize: UIGestureRecognizer) {
+        let location = gestureRecognize.location(in: sceneView)
+        let hitResults = sceneView.hitTest(location, options: [:])
+        if hitResults.count > 0, let tappedImageName = hitResults[0].node.name {
+            onDetectedImageTapped(imageKey: tappedImageName)
+        }
+        
+    }
+    
     // MARK: - Session management (Image detection setup)
 
     /// Prevents restarting the session while a restart is in progress.
@@ -107,9 +120,11 @@ extension ARQuidoViewController: ARSCNViewDelegate {
         }
 
         let referenceImage = imageAnchor.referenceImage
+        let imageName = referenceImage.name ?? ""
         updateQueue.async {
             let plane = SCNBox(width: referenceImage.physicalSize.width, height: referenceImage.physicalSize.height, length: 0.3, chamferRadius: 0.01)
             let planeNode = SCNNode(geometry: plane)
+            planeNode.name = imageName
             planeNode.opacity = 0.75
             planeNode.geometry?.firstMaterial?.diffuse.contents = UIColor(red: 205 / 255, green: 207 / 255, blue: 1.0, alpha: 1.0)
             //rotate plane to match assumed image orientation
@@ -120,7 +135,6 @@ extension ARQuidoViewController: ARSCNViewDelegate {
         }
 
         DispatchQueue.main.async {
-            let imageName = referenceImage.name ?? ""
             self.onDetect(imageKey: imageName)
         }
     }
@@ -234,4 +248,8 @@ extension ARQuidoViewController: ImageRecognitionDelegate {
     func onDetect(imageKey: String) {
         methodChannel.invokeMethod("scanner#onImageDetected", arguments: ["imageName": imageKey])
     }
+    
+    func onDetectedImageTapped(imageKey: String) {
+        methodChannel.invokeMethod("scanner#onDetectedImageTapped", arguments: ["imageName": imageKey])
+    }
 }

lib/src/ar_quido_method_channel.dart

@@ -36,6 +36,10 @@ class ARQuidoMethodChannel extends ARQuidoPlatform {
   @override
   Stream<ImageDetectedEvent> onImageDetected() => _scannerEventStreamController.stream.whereType<ImageDetectedEvent>();
 
+  @override
+  Stream<ImageTappedEvent> onDetectedImageTapped() =>
+      _scannerEventStreamController.stream.whereType<ImageTappedEvent>();
+
   @override
   Stream<RecognitionStartedEvent> onRecognitionStarted() =>
       _scannerEventStreamController.stream.whereType<RecognitionStartedEvent>();
@@ -67,6 +71,11 @@ class ARQuidoMethodChannel extends ARQuidoPlatform {
         final imageName = arguments['imageName'];
         _scannerEventStreamController.add(ImageDetectedEvent(imageName));
         break;
+      case 'scanner#onDetectedImageTapped':
+        final arguments = (call.arguments as Map).cast<String, String?>();
+        final imageName = arguments['imageName'];
+        _scannerEventStreamController.add(ImageTappedEvent(imageName));
+        break;
       case 'scanner#error':
         final arguments = (call.arguments as Map).cast<String, String?>();
         final error = arguments['errorCode'];

lib/src/ar_quido_platform.dart

@@ -36,6 +36,10 @@ abstract class ARQuidoPlatform extends PlatformInterface {
     throw UnimplementedError('onImageDetected() has not been implemented.');
   }
 
+  Stream<ImageTappedEvent> onDetectedImageTapped() {
+    throw UnimplementedError('onImageDetected() has not been implemented.');
+  }
+
   Stream<RecognitionStartedEvent> onRecognitionStarted() {
     throw UnimplementedError(
       'onRecognitionStarted() has not been implemented.',

lib/src/types/scanner_event.dart

@@ -6,6 +6,12 @@ class ImageDetectedEvent extends ScannerEvent {
   final String? imageName;
 }
 
+class ImageTappedEvent extends ScannerEvent {
+  ImageTappedEvent(this.imageName);
+
+  final String? imageName;
+}
+
 class RecognitionStartedEvent extends ScannerEvent {}
 
 class RecognitionResumedEvent extends ScannerEvent {}

lib/src/view/ar_quido_view.dart

@@ -11,6 +11,7 @@ class ARQuidoView extends StatefulWidget {
   const ARQuidoView({
     required this.referenceImageNames,
     required this.onImageDetected,
+    this.onDetectedImageTapped,
     this.onViewCreated,
     this.onRecognitionStarted,
     this.onRecognitionPaused,
@@ -22,6 +23,7 @@ class ARQuidoView extends StatefulWidget {
   final List<String> referenceImageNames;
   final void Function(ARQuidoViewController controller)? onViewCreated;
   final void Function(String? imageName) onImageDetected;
+  final void Function(String? imageName)? onDetectedImageTapped;
   final VoidCallback? onRecognitionStarted;
   final VoidCallback? onRecognitionPaused;
   final VoidCallback? onRecognitionResumed;

lib/src/view/ar_quido_view_controller.dart

@@ -28,37 +28,34 @@ class ARQuidoViewController {
     final scannerViewWidget = _scannerViewState.widget;
     if (scannerViewWidget.onRecognitionStarted != null) {
       _subscriptions.add(
-        platformInstance.onRecognitionStarted().listen(
-              (event) => _scannerViewState.widget.onRecognitionStarted!(),
-            ),
+        platformInstance.onRecognitionStarted().listen((event) => _scannerViewState.widget.onRecognitionStarted!()),
       );
     }
     if (scannerViewWidget.onRecognitionResumed != null) {
       _subscriptions.add(
-        platformInstance.onRecognitionResumed().listen(
-              (event) => _scannerViewState.widget.onRecognitionResumed!(),
-            ),
+        platformInstance.onRecognitionResumed().listen((event) => _scannerViewState.widget.onRecognitionResumed!()),
       );
     }
     if (scannerViewWidget.onRecognitionPaused != null) {
       _subscriptions.add(
-        platformInstance.onRecognitionPaused().listen(
-              (event) => _scannerViewState.widget.onRecognitionPaused!(),
-            ),
+        platformInstance.onRecognitionPaused().listen((event) => _scannerViewState.widget.onRecognitionPaused!()),
       );
     }
     if (scannerViewWidget.onError != null) {
       _subscriptions.add(
-        platformInstance.onError().listen(
-              (event) => _scannerViewState.widget.onError!(event.error),
-            ),
+        platformInstance.onError().listen((event) => _scannerViewState.widget.onError!(event.error)),
+      );
+    }
+    if (scannerViewWidget.onDetectedImageTapped != null) {
+      _subscriptions.add(
+        platformInstance
+            .onDetectedImageTapped()
+            .listen((event) => scannerViewWidget.onDetectedImageTapped!(event.imageName)),
       );
     }
 
     _subscriptions.add(
-      platformInstance.onImageDetected().listen(
-            (event) => scannerViewWidget.onImageDetected(event.imageName),
-          ),
+      platformInstance.onImageDetected().listen((event) => scannerViewWidget.onImageDetected(event.imageName)),
     );
   }
 }