Merge pull request #1048 from navaronbracke/fix_ios_torch_mode

fix: provide correct initial torch state

Author: navaronbracke

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 Bugs fixed:
 * Fixed a crash when the controller is disposed while it is still starting. [#1036](https://github.com/juliansteenbakker/mobile_scanner/pull/1036) (thanks @EArminjon !)
+* Fixed an issue that causes the initial torch state to be out of sync.
+
+Improvements:
+* Updated the lifeycle code sample to handle not-initialized controllers.
 
 ## 5.0.1
 

README.md

@@ -103,7 +103,11 @@ class MyState extends State<MyStatefulWidget> with WidgetsBindingObserver {
 
   @override
   void didChangeAppLifecycleState(AppLifecycleState state) {
-    super.didChangeAppLifecycleState(state);
+    // If the controller is not ready, do not try to start or stop it.
+    // Permission dialogs can trigger lifecycle changes before the controller is ready.
+    if (!controller.value.isInitialized) {
+      return;
+    }
 
     switch (state) {
       case AppLifecycleState.detached:

android/src/main/kotlin/dev/steenbakker/mobile_scanner/MobileScanner.kt

@@ -19,6 +19,7 @@ import androidx.camera.core.ExperimentalGetImage
 import androidx.camera.core.ImageAnalysis
 import androidx.camera.core.ImageProxy
 import androidx.camera.core.Preview
+import androidx.camera.core.TorchState
 import androidx.camera.core.resolutionselector.AspectRatioStrategy
 import androidx.camera.core.resolutionselector.ResolutionSelector
 import androidx.camera.core.resolutionselector.ResolutionStrategy
@@ -368,11 +369,22 @@ class MobileScanner(
             val height = resolution.height.toDouble()
             val portrait = (camera?.cameraInfo?.sensorRotationDegrees ?: 0) % 180 == 0
 
+            // Start with 'unavailable' torch state.
+            var currentTorchState: Int = -1
+
+            camera?.cameraInfo?.let {
+                if (!it.hasFlashUnit()) {
+                    return@let
+                }
+
+                currentTorchState = it.torchState.value ?: -1
+            }
+
             mobileScannerStartedCallback(
                 MobileScannerStartParameters(
                     if (portrait) width else height,
                     if (portrait) height else width,
-                    camera?.cameraInfo?.hasFlashUnit() ?: false,
+                    currentTorchState,
                     textureEntry!!.id(),
                     numberOfCameras ?: 0
                 )
@@ -411,13 +423,16 @@ class MobileScanner(
     /**
      * Toggles the flash light on or off.
      */
-    fun toggleTorch(enableTorch: Boolean) {
-        if (camera == null) {
-            return
-        }
+    fun toggleTorch() {
+        camera?.let {
+            if (!it.cameraInfo.hasFlashUnit()) {
+                return@let
+            }
 
-        if (camera?.cameraInfo?.hasFlashUnit() == true) {
-            camera?.cameraControl?.enableTorch(enableTorch)
+            when(it.cameraInfo.torchState.value) {
+                TorchState.OFF -> it.cameraControl.enableTorch(true)
+                TorchState.ON -> it.cameraControl.enableTorch(false)
+            }
         }
     }
 

android/src/main/kotlin/dev/steenbakker/mobile_scanner/MobileScannerHandler.kt

@@ -74,6 +74,7 @@ class MobileScannerHandler(
     private var mobileScanner: MobileScanner? = null
 
     private val torchStateCallback: TorchStateCallback = {state: Int ->
+        // Off = 0, On = 1
         barcodeHandler.publishEvent(mapOf("name" to "torchState", "data" to state))
     }
 
@@ -121,8 +122,8 @@ class MobileScannerHandler(
                     }
                 })
             "start" -> start(call, result)
-            "torch" -> toggleTorch(call, result)
             "stop" -> stop(result)
+            "toggleTorch" -> toggleTorch(result)
             "analyzeImage" -> analyzeImage(call, result)
             "setScale" -> setScale(call, result)
             "resetScale" -> resetScale(result)
@@ -167,7 +168,7 @@ class MobileScannerHandler(
         val position =
             if (facing == 0) CameraSelector.DEFAULT_FRONT_CAMERA else CameraSelector.DEFAULT_BACK_CAMERA
 
-        val detectionSpeed: DetectionSpeed = DetectionSpeed.values().first { it.intValue == speed}
+        val detectionSpeed: DetectionSpeed = DetectionSpeed.entries.first { it.intValue == speed}
 
         mobileScanner!!.start(
             barcodeScannerOptions,
@@ -182,7 +183,7 @@ class MobileScannerHandler(
                     result.success(mapOf(
                         "textureId" to it.id,
                         "size" to mapOf("width" to it.width, "height" to it.height),
-                        "torchable" to it.hasFlashUnit,
+                        "currentTorchState" to it.currentTorchState,
                         "numberOfCameras" to it.numberOfCameras
                     ))
                 }
@@ -243,8 +244,8 @@ class MobileScannerHandler(
         mobileScanner!!.analyzeImage(uri, analyzeImageSuccessCallback, analyzeImageErrorCallback)
     }
 
-    private fun toggleTorch(call: MethodCall, result: MethodChannel.Result) {
-        mobileScanner!!.toggleTorch(call.arguments == 1)
+    private fun toggleTorch(result: MethodChannel.Result) {
+        mobileScanner?.toggleTorch()
         result.success(null)
     }
 

android/src/main/kotlin/dev/steenbakker/mobile_scanner/objects/MobileScannerStartParameters.kt

@@ -3,7 +3,7 @@ package dev.steenbakker.mobile_scanner.objects
 class MobileScannerStartParameters(
     val width: Double = 0.0,
     val height: Double,
-    val hasFlashUnit: Boolean,
+    val currentTorchState: Int,
     val id: Long,
     val numberOfCameras: Int
 )

example/ios/Runner.xcodeproj/project.pbxproj

@@ -198,6 +198,7 @@
 				9705A1C41CF9048500538489 /* Embed Frameworks */,
 				3B06AD1E1E4923F5004D2608 /* Thin Binary */,
 				3DBCC0215D7BED1D9A756EA3 /* [CP] Embed Pods Frameworks */,
+				BB0C8EA8DA81A75DE53F052F /* [CP] Copy Pods Resources */,
 			);
 			buildRules = (
 			);
@@ -215,7 +216,7 @@
 			isa = PBXProject;
 			attributes = {
 				BuildIndependentTargetsInParallel = YES;
-				LastUpgradeCheck = 1430;
+				LastUpgradeCheck = 1510;
 				ORGANIZATIONNAME = "";
 				TargetAttributes = {
 					331C8080294A63A400263BE5 = {
@@ -317,6 +318,23 @@
 			shellPath = /bin/sh;
 			shellScript = "/bin/sh \"$FLUTTER_ROOT/packages/flutter_tools/bin/xcode_backend.sh\" build";
 		};
+		BB0C8EA8DA81A75DE53F052F /* [CP] Copy Pods Resources */ = {
+			isa = PBXShellScriptBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			inputFileListPaths = (
+				"${PODS_ROOT}/Target Support Files/Pods-Runner/Pods-Runner-resources-${CONFIGURATION}-input-files.xcfilelist",
+			);
+			name = "[CP] Copy Pods Resources";
+			outputFileListPaths = (
+				"${PODS_ROOT}/Target Support Files/Pods-Runner/Pods-Runner-resources-${CONFIGURATION}-output-files.xcfilelist",
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+			shellPath = /bin/sh;
+			shellScript = "\"${PODS_ROOT}/Target Support Files/Pods-Runner/Pods-Runner-resources.sh\"\n";
+			showEnvVarsInLog = 0;
+		};
 		C7DE006A696F551C4E067E41 /* [CP] Check Pods Manifest.lock */ = {
 			isa = PBXShellScriptBuildPhase;
 			buildActionMask = 2147483647;
@@ -495,7 +513,7 @@
 				CURRENT_PROJECT_VERSION = 1;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
-				PRODUCT_BUNDLE_IDENTIFIER = com.example.mobile-scanner.RunnerTests;
+				PRODUCT_BUNDLE_IDENTIFIER = "com.example.mobile-scanner.RunnerTests";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_ACTIVE_COMPILATION_CONDITIONS = DEBUG;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
@@ -513,7 +531,7 @@
 				CURRENT_PROJECT_VERSION = 1;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
-				PRODUCT_BUNDLE_IDENTIFIER = com.example.mobile-scanner.RunnerTests;
+				PRODUCT_BUNDLE_IDENTIFIER = "com.example.mobile-scanner.RunnerTests";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_VERSION = 5.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/Runner.app/$(BUNDLE_EXECUTABLE_FOLDER_PATH)/Runner";
@@ -529,7 +547,7 @@
 				CURRENT_PROJECT_VERSION = 1;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
-				PRODUCT_BUNDLE_IDENTIFIER = com.example.mobile-scanner.RunnerTests;
+				PRODUCT_BUNDLE_IDENTIFIER = "com.example.mobile-scanner.RunnerTests";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_VERSION = 5.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/Runner.app/$(BUNDLE_EXECUTABLE_FOLDER_PATH)/Runner";

example/ios/Runner.xcodeproj/xcshareddata/xcschemes/Runner.xcscheme

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "1430"
+   LastUpgradeVersion = "1510"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"

example/ios/Runner/Info.plist

@@ -2,6 +2,8 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
+	<key>CADisableMinimumFrameDurationOnPhone</key>
+	<true/>
 	<key>CFBundleDevelopmentRegion</key>
 	<string>$(DEVELOPMENT_LANGUAGE)</string>
 	<key>CFBundleDisplayName</key>
@@ -28,6 +30,8 @@
 	<string>This app needs camera access to scan QR codes</string>
 	<key>NSPhotoLibraryUsageDescription</key>
 	<string>This app needs photos access to get QR code from photo library</string>
+	<key>UIApplicationSupportsIndirectInputEvents</key>
+	<true/>
 	<key>UILaunchStoryboardName</key>
 	<string>LaunchScreen</string>
 	<key>UIMainStoryboardFile</key>
@@ -47,9 +51,5 @@
 	</array>
 	<key>UIViewControllerBasedStatusBarAppearance</key>
 	<false/>
-	<key>CADisableMinimumFrameDurationOnPhone</key>
-	<true/>
-	<key>UIApplicationSupportsIndirectInputEvents</key>
-	<true/>	
 </dict>
 </plist>

example/lib/barcode_scanner_controller.dart

@@ -63,7 +63,9 @@ class _BarcodeScannerWithControllerState
 
   @override
   void didChangeAppLifecycleState(AppLifecycleState state) {
-    super.didChangeAppLifecycleState(state);
+    if (!controller.value.isInitialized) {
+      return;
+    }
 
     switch (state) {
       case AppLifecycleState.detached:

example/lib/scanner_button_widgets.dart

@@ -138,6 +138,15 @@ class ToggleFlashlightButton extends StatelessWidget {
         }
 
         switch (state.torchState) {
+          case TorchState.auto:
+            return IconButton(
+              color: Colors.white,
+              iconSize: 32.0,
+              icon: const Icon(Icons.flash_auto),
+              onPressed: () async {
+                await controller.toggleTorch();
+              },
+            );
           case TorchState.off:
             return IconButton(
               color: Colors.white,