Merge pull request #21 from juliansteenbakker/bug/start-stop-crash

bugfix: Fixed crash on multiple start() or stop() calls.

Merge pull request #21 from juliansteenbakker/bug/start-stop-crash
bugfix: Fixed crash on multiple start() or stop() calls.
Julian Steenbakker · GitHub
Commit ff410a16ec7048d88e0d83bb5aed517fbf39664d ff410a16 2 parents 2a258e1b eba377f0
Showing 8 changed files with 204 additions and 108 deletions
analysis_options.yaml
android/src/main/kotlin/dev/steenbakker/mobile_scanner/MobileScanner.kt
example/macos/Podfile
example/macos/Runner.xcodeproj/project.pbxproj
ios/Classes/SwiftMobileScannerPlugin.swift
lib/src/mobile_scanner_controller.dart
macos/Classes/MobileScannerPlugin.swift
macos/Classes/Util.swift
--- a/analysis_options.yaml
View file @ff410a1
+++ b/analysis_options.yaml
View file @ff410a1
-include: package:flutter_lints/flutter.yaml
+include: package:flutter_lints/flutter.yaml
+
+linter:
+  rules:
+    unawaited_futures: true
--- a/android/src/main/kotlin/dev/steenbakker/mobile_scanner/MobileScanner.kt
View file @ff410a1
+++ b/android/src/main/kotlin/dev/steenbakker/mobile_scanner/MobileScanner.kt
View file @ff410a1
@@ -38,8 +38,8 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
     private var camera: Camera? = null
     private var textureEntry: TextureRegistry.SurfaceTextureEntry? = null
-    @AnalyzeMode
-    private var analyzeMode: Int = AnalyzeMode.NONE
+//    @AnalyzeMode
+//    private var analyzeMode: Int = AnalyzeMode.NONE
     @ExperimentalGetImage
     override fun onMethodCall(@NonNull call: MethodCall, @NonNull result: MethodChannel.Result) {
@@ -47,8 +47,8 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
             "state" -> checkPermission(result)
             "request" -> requestPermission(result)
             "start" -> start(call, result)
-            "torch" -> switchTorch(call, result)
-            "analyze" -> switchAnalyzeMode(call, result)
+            "torch" -> toggleTorch(call, result)
+//            "analyze" -> switchAnalyzeMode(call, result)
             "stop" -> stop(result)
             else -> result.notImplemented()
         }
@@ -92,8 +92,8 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
     @ExperimentalGetImage
     val analyzer = ImageAnalysis.Analyzer { imageProxy -> // YUV_420_888 format
-        when (analyzeMode) {
-            AnalyzeMode.BARCODE -> {
+//        when (analyzeMode) {
+//            AnalyzeMode.BARCODE -> {
                 val mediaImage = imageProxy.image ?: return@Analyzer
                 val inputImage = InputImage.fromMediaImage(mediaImage, imageProxy.imageInfo.rotationDegrees)
@@ -106,9 +106,9 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
                         }
                         .addOnFailureListener { e -> Log.e(TAG, e.message, e) }
                         .addOnCompleteListener { imageProxy.close() }
-            }
-            else -> imageProxy.close()
-        }
+//            }
+//            else -> imageProxy.close()
+//        }
     }
@@ -116,6 +116,10 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
     @ExperimentalGetImage
     private fun start(call: MethodCall, result: MethodChannel.Result) {
+        if (camera != null) {
+            result.error(TAG, "Called start() while already started!", null)
+            return
+        }
         val facing: Int = call.argument<Int>("facing") ?: 0
         val ratio: Int? = call.argument<Int>("ratio")
@@ -186,24 +190,32 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
         }, executor)
     }
-    private fun switchTorch(call: MethodCall, result: MethodChannel.Result) {
-        val state = call.arguments == 1
-        camera!!.cameraControl.enableTorch(state)
+    private fun toggleTorch(call: MethodCall, result: MethodChannel.Result) {
+        if (camera == null) {
+            result.error(TAG,"Called toggleTorch() while stopped!", null)
+            return
+        }
+        camera!!.cameraControl.enableTorch(call.arguments == 1)
         result.success(null)
     }
-    private fun switchAnalyzeMode(call: MethodCall, result: MethodChannel.Result) {
-        analyzeMode = call.arguments as Int
-        result.success(null)
-    }
+//    private fun switchAnalyzeMode(call: MethodCall, result: MethodChannel.Result) {
+//        analyzeMode = call.arguments as Int
+//        result.success(null)
+//    }
     private fun stop(result: MethodChannel.Result) {
+        if (camera == null) {
+            result.error(TAG,"Called stop() while already stopped!", null)
+            return
+        }
+
         val owner = activity as LifecycleOwner
         camera!!.cameraInfo.torchState.removeObservers(owner)
         cameraProvider!!.unbindAll()
         textureEntry!!.release()
-        analyzeMode = AnalyzeMode.NONE
+//        analyzeMode = AnalyzeMode.NONE
         camera = null
         textureEntry = null
         cameraProvider = null
--- a/example/macos/Podfile
View file @ff410a1
+++ b/example/macos/Podfile
View file @ff410a1
-platform :osx, '10.11'
+platform :osx, '10.13'
 # CocoaPods analytics sends network stats synchronously affecting flutter build latency.
 ENV['COCOAPODS_DISABLE_STATS'] = 'true'
--- a/example/macos/Runner.xcodeproj/project.pbxproj
View file @ff410a1
+++ b/example/macos/Runner.xcodeproj/project.pbxproj
View file @ff410a1
@@ -26,7 +26,7 @@
 		33CC10F32044A3C60003C045 /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 33CC10F22044A3C60003C045 /* Assets.xcassets */; };
 		33CC10F62044A3C60003C045 /* MainMenu.xib in Resources */ = {isa = PBXBuildFile; fileRef = 33CC10F42044A3C60003C045 /* MainMenu.xib */; };
 		33CC11132044BFA00003C045 /* MainFlutterWindow.swift in Sources */ = {isa = PBXBuildFile; fileRef = 33CC11122044BFA00003C045 /* MainFlutterWindow.swift */; };
-		5225F51353DA345E2811B6A4 /* Pods_Runner.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 65E614A1DF8B88C7B0CE1B97 /* Pods_Runner.framework */; };
+		5B9BD2ADBC68B74D80B57DF1 /* Pods_Runner.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = EC099C2B6D6B30BFB3FA6DB8 /* Pods_Runner.framework */; };
 /* End PBXBuildFile section */
 /* Begin PBXContainerItemProxy section */
@@ -67,12 +67,12 @@
 		33E51913231747F40026EE4D /* DebugProfile.entitlements */ = {isa = PBXFileReference; lastKnownFileType = text.plist.entitlements; path = DebugProfile.entitlements; sourceTree = "<group>"; };
 		33E51914231749380026EE4D /* Release.entitlements */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.entitlements; path = Release.entitlements; sourceTree = "<group>"; };
 		33E5194F232828860026EE4D /* AppInfo.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; path = AppInfo.xcconfig; sourceTree = "<group>"; };
-		65E614A1DF8B88C7B0CE1B97 /* Pods_Runner.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_Runner.framework; sourceTree = BUILT_PRODUCTS_DIR; };
+		3CEE8DB43A84811F33EB0202 /* Pods-Runner.profile.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-Runner.profile.xcconfig"; path = "Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig"; sourceTree = "<group>"; };
 		7AFA3C8E1D35360C0083082E /* Release.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; path = Release.xcconfig; sourceTree = "<group>"; };
 		9740EEB21CF90195004384FC /* Debug.xcconfig */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.xcconfig; path = Debug.xcconfig; sourceTree = "<group>"; };
-		CB0901144E09E7D7CA20584F /* Pods-Runner.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-Runner.debug.xcconfig"; path = "Target Support Files/Pods-Runner/Pods-Runner.debug.xcconfig"; sourceTree = "<group>"; };
-		D522F9F6F348C5944077606B /* Pods-Runner.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-Runner.release.xcconfig"; path = "Target Support Files/Pods-Runner/Pods-Runner.release.xcconfig"; sourceTree = "<group>"; };
-		F63009B5E287A1C82F9D7D2F /* Pods-Runner.profile.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-Runner.profile.xcconfig"; path = "Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig"; sourceTree = "<group>"; };
+		A1CBC07680A8ED396DBB68C0 /* Pods-Runner.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-Runner.release.xcconfig"; path = "Target Support Files/Pods-Runner/Pods-Runner.release.xcconfig"; sourceTree = "<group>"; };
+		CAD760C57A57D903AB03B47A /* Pods-Runner.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-Runner.debug.xcconfig"; path = "Target Support Files/Pods-Runner/Pods-Runner.debug.xcconfig"; sourceTree = "<group>"; };
+		EC099C2B6D6B30BFB3FA6DB8 /* Pods_Runner.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_Runner.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 /* End PBXFileReference section */
 /* Begin PBXFrameworksBuildPhase section */
@@ -80,19 +80,27 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				5225F51353DA345E2811B6A4 /* Pods_Runner.framework in Frameworks */,
+				5B9BD2ADBC68B74D80B57DF1 /* Pods_Runner.framework in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
 /* End PBXFrameworksBuildPhase section */
 /* Begin PBXGroup section */
+		18927D60C719EB75FC0A6633 /* Frameworks */ = {
+			isa = PBXGroup;
+			children = (
+				EC099C2B6D6B30BFB3FA6DB8 /* Pods_Runner.framework */,
+			);
+			name = Frameworks;
+			sourceTree = "<group>";
+		};
 		20F8C9AA20C2A495C125E194 /* Pods */ = {
 			isa = PBXGroup;
 			children = (
-				CB0901144E09E7D7CA20584F /* Pods-Runner.debug.xcconfig */,
-				D522F9F6F348C5944077606B /* Pods-Runner.release.xcconfig */,
-				F63009B5E287A1C82F9D7D2F /* Pods-Runner.profile.xcconfig */,
+				CAD760C57A57D903AB03B47A /* Pods-Runner.debug.xcconfig */,
+				A1CBC07680A8ED396DBB68C0 /* Pods-Runner.release.xcconfig */,
+				3CEE8DB43A84811F33EB0202 /* Pods-Runner.profile.xcconfig */,
 			);
 			path = Pods;
 			sourceTree = "<group>";
@@ -115,7 +123,7 @@
 				33CEB47122A05771004F2AC0 /* Flutter */,
 				33CC10EE2044A3C60003C045 /* Products */,
 				20F8C9AA20C2A495C125E194 /* Pods */,
-				3539353E79638640B4999C09 /* Frameworks */,
+				18927D60C719EB75FC0A6633 /* Frameworks */,
 			);
 			sourceTree = "<group>";
 		};
@@ -162,14 +170,6 @@
 			path = Runner;
 			sourceTree = "<group>";
 		};
-		3539353E79638640B4999C09 /* Frameworks */ = {
-			isa = PBXGroup;
-			children = (
-				65E614A1DF8B88C7B0CE1B97 /* Pods_Runner.framework */,
-			);
-			name = Frameworks;
-			sourceTree = "<group>";
-		};
 /* End PBXGroup section */
 /* Begin PBXNativeTarget section */
@@ -177,13 +177,13 @@
 			isa = PBXNativeTarget;
 			buildConfigurationList = 33CC10FB2044A3C60003C045 /* Build configuration list for PBXNativeTarget "Runner" */;
 			buildPhases = (
-				696298230BDAD783AEC51C81 /* [CP] Check Pods Manifest.lock */,
+				20903D1E9D9F08576541FFD7 /* [CP] Check Pods Manifest.lock */,
 				33CC10E92044A3C60003C045 /* Sources */,
 				33CC10EA2044A3C60003C045 /* Frameworks */,
 				33CC10EB2044A3C60003C045 /* Resources */,
 				33CC110E2044A8840003C045 /* Bundle Framework */,
 				3399D490228B24CF009A79C7 /* ShellScript */,
-				8A90D2BC4083C5ACCEEBF32B /* [CP] Embed Pods Frameworks */,
+				DF45614760BB9B24F49B2055 /* [CP] Embed Pods Frameworks */,
 			);
 			buildRules = (
 			);
@@ -253,7 +253,7 @@
 /* End PBXResourcesBuildPhase section */
 /* Begin PBXShellScriptBuildPhase section */
-		3399D490228B24CF009A79C7 /* ShellScript */ = {
+		20903D1E9D9F08576541FFD7 /* [CP] Check Pods Manifest.lock */ = {
 			isa = PBXShellScriptBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
@@ -261,58 +261,58 @@
 			inputFileListPaths = (
 			);
 			inputPaths = (
+				"${PODS_PODFILE_DIR_PATH}/Podfile.lock",
+				"${PODS_ROOT}/Manifest.lock",
 			);
+			name = "[CP] Check Pods Manifest.lock";
 			outputFileListPaths = (
 			);
 			outputPaths = (
+				"$(DERIVED_FILE_DIR)/Pods-Runner-checkManifestLockResult.txt",
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
-			shellScript = "echo \"$PRODUCT_NAME.app\" > \"$PROJECT_DIR\"/Flutter/ephemeral/.app_filename && \"$FLUTTER_ROOT\"/packages/flutter_tools/bin/macos_assemble.sh embed\n";
+			shellScript = "diff \"${PODS_PODFILE_DIR_PATH}/Podfile.lock\" \"${PODS_ROOT}/Manifest.lock\" > /dev/null\nif [ $? != 0 ] ; then\n    # print error to STDERR\n    echo \"error: The sandbox is not in sync with the Podfile.lock. Run 'pod install' or update your CocoaPods installation.\" >&2\n    exit 1\nfi\n# This output is used by Xcode 'outputs' to avoid re-running this script phase.\necho \"SUCCESS\" > \"${SCRIPT_OUTPUT_FILE_0}\"\n";
+			showEnvVarsInLog = 0;
 		};
-		33CC111E2044C6BF0003C045 /* ShellScript */ = {
+		3399D490228B24CF009A79C7 /* ShellScript */ = {
 			isa = PBXShellScriptBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
 			);
 			inputFileListPaths = (
-				Flutter/ephemeral/FlutterInputs.xcfilelist,
 			);
 			inputPaths = (
-				Flutter/ephemeral/tripwire,
 			);
 			outputFileListPaths = (
-				Flutter/ephemeral/FlutterOutputs.xcfilelist,
 			);
 			outputPaths = (
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
-			shellScript = "\"$FLUTTER_ROOT\"/packages/flutter_tools/bin/macos_assemble.sh && touch Flutter/ephemeral/tripwire";
+			shellScript = "echo \"$PRODUCT_NAME.app\" > \"$PROJECT_DIR\"/Flutter/ephemeral/.app_filename && \"$FLUTTER_ROOT\"/packages/flutter_tools/bin/macos_assemble.sh embed\n";
 		};
-		696298230BDAD783AEC51C81 /* [CP] Check Pods Manifest.lock */ = {
+		33CC111E2044C6BF0003C045 /* ShellScript */ = {
 			isa = PBXShellScriptBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
 			);
 			inputFileListPaths = (
+				Flutter/ephemeral/FlutterInputs.xcfilelist,
 			);
 			inputPaths = (
-				"${PODS_PODFILE_DIR_PATH}/Podfile.lock",
-				"${PODS_ROOT}/Manifest.lock",
+				Flutter/ephemeral/tripwire,
 			);
-			name = "[CP] Check Pods Manifest.lock";
 			outputFileListPaths = (
+				Flutter/ephemeral/FlutterOutputs.xcfilelist,
 			);
 			outputPaths = (
-				"$(DERIVED_FILE_DIR)/Pods-Runner-checkManifestLockResult.txt",
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
-			shellScript = "diff \"${PODS_PODFILE_DIR_PATH}/Podfile.lock\" \"${PODS_ROOT}/Manifest.lock\" > /dev/null\nif [ $? != 0 ] ; then\n    # print error to STDERR\n    echo \"error: The sandbox is not in sync with the Podfile.lock. Run 'pod install' or update your CocoaPods installation.\" >&2\n    exit 1\nfi\n# This output is used by Xcode 'outputs' to avoid re-running this script phase.\necho \"SUCCESS\" > \"${SCRIPT_OUTPUT_FILE_0}\"\n";
-			showEnvVarsInLog = 0;
+			shellScript = "\"$FLUTTER_ROOT\"/packages/flutter_tools/bin/macos_assemble.sh && touch Flutter/ephemeral/tripwire";
 		};
-		8A90D2BC4083C5ACCEEBF32B /* [CP] Embed Pods Frameworks */ = {
+		DF45614760BB9B24F49B2055 /* [CP] Embed Pods Frameworks */ = {
 			isa = PBXShellScriptBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
--- a/ios/Classes/SwiftMobileScannerPlugin.swift
View file @ff410a1
+++ b/ios/Classes/SwiftMobileScannerPlugin.swift
View file @ff410a1
@@ -23,7 +23,7 @@ public class SwiftMobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHan
     var latestBuffer: CVImageBuffer!
-    var analyzeMode: Int = 0
+//    var analyzeMode: Int = 0
     var analyzing: Bool = false
     var position = AVCaptureDevice.Position.back
@@ -53,9 +53,9 @@ public class SwiftMobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHan
         case "start":
             start(call, result)
         case "torch":
-            switchTorch(call, result)
-        case "analyze":
-            switchAnalyzeMode(call, result)
+            toggleTorch(call, result)
+//        case "analyze":
+//            switchAnalyzeMode(call, result)
         case "stop":
             stop(result)
         default:
@@ -89,10 +89,10 @@ public class SwiftMobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHan
         latestBuffer = CMSampleBufferGetImageBuffer(sampleBuffer)
         registry.textureFrameAvailable(textureId)
-        switch analyzeMode {
-        case 1: // barcode
+//        switch analyzeMode {
+//        case 1: // barcode
             if analyzing {
-                break
+                return
             }
             analyzing = true
             let buffer = CMSampleBufferGetImageBuffer(sampleBuffer)
@@ -112,9 +112,9 @@ public class SwiftMobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHan
                 }
                 analyzing = false
             }
-        default: // none
-            break
-        }
+//        default: // none
+//            break
+//        }
     }
     func imageOrientation(
@@ -154,6 +154,13 @@ public class SwiftMobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHan
     }
     func start(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
+        if (device != nil) {
+            result(FlutterError(code: "MobileScanner",
+                                    message: "Called start() while already started!",
+                                    details: nil))
+            return
+        }
+        
         textureId = registry.register(self)
         captureSession = AVCaptureSession()
@@ -173,6 +180,13 @@ public class SwiftMobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHan
             device = AVCaptureDevice.devices(for: .video).filter({$0.position == position}).first
         }
+        if (device == nil) {
+            result(FlutterError(code: "MobileScanner",
+                                    message: "No camera found or failed to open camera!",
+                                    details: nil))
+            return
+        }
+        
         // Enable the torch if parameter is set and torch is available
         if (device.hasTorch && device.isTorchAvailable) {
             do {
@@ -219,7 +233,13 @@ public class SwiftMobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHan
         result(answer)
     }
-    func switchTorch(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
+    func toggleTorch(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
+        if (device == nil) {
+            result(FlutterError(code: "MobileScanner",
+                                    message: "Called toggleTorch() while stopped!",
+                                    details: nil))
+            return
+        }
         do {
             try device.lockForConfiguration()
             device.torchMode = call.arguments as! Int == 1 ? .on : .off
@@ -230,12 +250,18 @@ public class SwiftMobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHan
         }
     }
-    func switchAnalyzeMode(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
-        analyzeMode = call.arguments as! Int
-        result(nil)
-    }
+//    func switchAnalyzeMode(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
+//        analyzeMode = call.arguments as! Int
+//        result(nil)
+//    }
     func stop(_ result: FlutterResult) {
+        if (device == nil) {
+            result(FlutterError(code: "MobileScanner",
+                                    message: "Called stop() while already stopped!",
+                                    details: nil))
+            return
+        }
         captureSession.stopRunning()
         for input in captureSession.inputs {
             captureSession.removeInput(input)
@@ -246,7 +272,7 @@ public class SwiftMobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHan
         device.removeObserver(self, forKeyPath: #keyPath(AVCaptureDevice.torchMode))
         registry.unregisterTexture(textureId)
-        analyzeMode = 0
+//        analyzeMode = 0
         latestBuffer = nil
         captureSession = nil
         device = nil
--- a/lib/src/mobile_scanner_controller.dart
View file @ff410a1
+++ b/lib/src/mobile_scanner_controller.dart
View file @ff410a1
@@ -27,7 +27,7 @@ enum TorchState {
   on,
 }
-enum AnalyzeMode { none, barcode }
+// enum AnalyzeMode { none, barcode }
 class MobileScannerController {
   MethodChannel methodChannel =
@@ -62,9 +62,9 @@ class MobileScannerController {
     // Sets analyze mode and barcode stream
     barcodesController = StreamController.broadcast(
-      onListen: () => setAnalyzeMode(AnalyzeMode.barcode.index),
-      onCancel: () => setAnalyzeMode(AnalyzeMode.none.index),
-    );
+        // onListen: () => setAnalyzeMode(AnalyzeMode.barcode.index),
+        // onCancel: () => setAnalyzeMode(AnalyzeMode.none.index),
+        );
     start();
@@ -94,12 +94,13 @@ class MobileScannerController {
     }
   }
-  void setAnalyzeMode(int mode) {
-    if (hashCode != _controllerHashcode) {
-      return;
-    }
-    methodChannel.invokeMethod('analyze', mode);
-  }
+  // TODO: Add more analyzers like text analyzer
+  // void setAnalyzeMode(int mode) {
+  //   if (hashCode != _controllerHashcode) {
+  //     return;
+  //   }
+  //   methodChannel.invokeMethod('analyze', mode);
+  // }
   // List<BarcodeFormats>? formats = _defaultBarcodeFormats,
   /// Start barcode scanning. This will first check if the required permissions
@@ -107,7 +108,7 @@ class MobileScannerController {
   Future<void> start() async {
     ensure('startAsync');
-    setAnalyzeMode(AnalyzeMode.barcode.index);
+    // setAnalyzeMode(AnalyzeMode.barcode.index);
     // Check authorization status
     MobileScannerState state =
         MobileScannerState.values[await methodChannel.invokeMethod('state')];
@@ -132,8 +133,15 @@ class MobileScannerController {
     if (torchEnabled != null) arguments['torch'] = torchEnabled;
     // Start the camera with arguments
-    final Map<String, dynamic>? startResult = await methodChannel
-        .invokeMapMethod<String, dynamic>('start', arguments);
+    Map<String, dynamic>? startResult = {};
+    try {
+      startResult = await methodChannel.invokeMapMethod<String, dynamic>(
+          'start', arguments);
+    } on PlatformException catch (error) {
+      debugPrint('${error.code}: ${error.message}');
+      // setAnalyzeMode(AnalyzeMode.none.index);
+      return;
+    }
     if (startResult == null) {
       throw PlatformException(code: 'INITIALIZATION ERROR');
@@ -146,17 +154,32 @@ class MobileScannerController {
         hasTorch: hasTorch);
   }
-  Future<void> stop() async => await methodChannel.invokeMethod('stop');
+  Future<void> stop() async {
+    try {
+      await methodChannel.invokeMethod('stop');
+    } on PlatformException catch (error) {
+      debugPrint('${error.code}: ${error.message}');
+    }
+  }
   /// Switches the torch on or off.
   ///
   /// Only works if torch is available.
-  void toggleTorch() {
+  Future<void> toggleTorch() async {
     ensure('toggleTorch');
-    if (!hasTorch) return;
+    if (!hasTorch) {
+      debugPrint('Device has no torch/flash.');
+      return;
+    }
+
     TorchState state =
         torchState.value == TorchState.off ? TorchState.on : TorchState.off;
-    methodChannel.invokeMethod('torch', state.index);
+
+    try {
+      await methodChannel.invokeMethod('torch', state.index);
+    } on PlatformException catch (error) {
+      debugPrint('${error.code}: ${error.message}');
+    }
   }
   /// Switches the torch on or off.
@@ -164,10 +187,16 @@ class MobileScannerController {
   /// Only works if torch is available.
   Future<void> switchCamera() async {
     ensure('switchCamera');
-    await stop();
+    try {
+      await methodChannel.invokeMethod('stop');
+    } on PlatformException catch (error) {
+      debugPrint(
+          '${error.code}: camera is stopped! Please start before switching camera.');
+      return;
+    }
     facing =
         facing == CameraFacing.back ? CameraFacing.front : CameraFacing.back;
-    start();
+    await start();
   }
   /// Disposes the controller and closes all listeners.
--- a/macos/Classes/MobileScannerPlugin.swift
View file @ff410a1
+++ b/macos/Classes/MobileScannerPlugin.swift
View file @ff410a1
@@ -22,7 +22,7 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
     var latestBuffer: CVImageBuffer!
-    var analyzeMode: Int = 0
+//    var analyzeMode: Int = 0
     var analyzing: Bool = false
     var position = AVCaptureDevice.Position.back
@@ -52,9 +52,9 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
         case "start":
             start(call, result)
         case "torch":
-            switchTorch(call, result)
-        case "analyze":
-            switchAnalyzeMode(call, result)
+            toggleTorch(call, result)
+//        case "analyze":
+//            switchAnalyzeMode(call, result)
         case "stop":
             stop(result)
         default:
@@ -92,14 +92,14 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
         latestBuffer = CMSampleBufferGetImageBuffer(sampleBuffer)
         registry.textureFrameAvailable(textureId)
-        switch analyzeMode {
-        case 1: // barcode
+//        switch analyzeMode {
+//        case 1: // barcode
             // Limit the analyzer because the texture output will freeze otherwise
             if i / 10 == 1 {
                 i = 0
             } else {
-                break
+                return
             }
                 let imageRequestHandler = VNImageRequestHandler(
                     cvPixelBuffer: latestBuffer,
@@ -129,9 +129,9 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
               print(error)
             }
-        default: // none
-            break
-        }
+//        default: // none
+//            break
+//        }
     }
     func checkPermission(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
@@ -159,6 +159,13 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
     }
     func start(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
+        if (device != nil) {
+            result(FlutterError(code: "MobileScanner",
+                                    message: "Called start() while already started!",
+                                    details: nil))
+            return
+        }
+        
         textureId = registry.register(self)
         captureSession = AVCaptureSession()
@@ -178,6 +185,13 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
             device = AVCaptureDevice.devices(for: .video).filter({$0.position == position}).first
         }
+        if (device == nil) {
+            result(FlutterError(code: "MobileScanner",
+                                    message: "No camera found or failed to open camera!",
+                                    details: nil))
+            return
+        }
+        
         // Enable the torch if parameter is set and torch is available
         if (device.hasTorch) {
             do {
@@ -222,7 +236,13 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
         result(answer)
     }
-    func switchTorch(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
+    func toggleTorch(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
+        if (device == nil) {
+            result(FlutterError(code: "MobileScanner",
+                                    message: "Called toggleTorch() while stopped!",
+                                    details: nil))
+            return
+        }
         do {
             try device.lockForConfiguration()
             device.torchMode = call.arguments as! Int == 1 ? .on : .off
@@ -232,13 +252,19 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
             result(FlutterError(code: error.localizedDescription, message: nil, details: nil))
         }
     }
-    
-    func switchAnalyzeMode(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
-        analyzeMode = call.arguments as! Int
-        result(nil)
-    }
-    
+
+//    func switchAnalyzeMode(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
+//        analyzeMode = call.arguments as! Int
+//        result(nil)
+//    }
+
     func stop(_ result: FlutterResult) {
+        if (device == nil) {
+            result(FlutterError(code: "MobileScanner",
+                                    message: "Called stop() while already stopped!",
+                                    details: nil))
+            return
+        }
         captureSession.stopRunning()
         for input in captureSession.inputs {
             captureSession.removeInput(input)
@@ -249,7 +275,7 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
         device.removeObserver(self, forKeyPath: #keyPath(AVCaptureDevice.torchMode))
         registry.unregisterTexture(textureId)
-        analyzeMode = 0
+//        analyzeMode = 0
         latestBuffer = nil
         captureSession = nil
         device = nil
--- a/macos/Classes/Util.swift deleted 100644 → 0
View file @2a258e1
+++ b/macos/Classes/Util.swift deleted 100644 → 0
View file @2a258e1
-