Merge pull request #213 from juliuscanute/86-select-camera-on-start

86 select camera on start

android/src/main/kotlin/net/touchcapture/qr/flutterqr/FlutterQrPlugin.kt

@@ -63,7 +63,6 @@ class FlutterQrPlugin : FlutterPlugin, ActivityAware {
     inner class CameraRequestPermissionsListener : PluginRegistry.RequestPermissionsResultListener {
         override fun onRequestPermissionsResult(id: Int, permissions: Array<String>, grantResults: IntArray): Boolean {
             if (id == Shared.CAMERA_REQUEST_ID && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
-                Shared.cameraPermissionContinuation?.run()
                 return true
             }
             return false

android/src/main/kotlin/net/touchcapture/qr/flutterqr/QRView.kt

@@ -3,13 +3,13 @@ package net.touchcapture.qr.flutterqr
 import android.Manifest
 import android.app.Activity
 import android.app.Application
-import android.content.Context
 import android.content.pm.PackageManager
 import android.os.Bundle
 import android.view.View
 import com.google.zxing.ResultPoint
 import android.hardware.Camera.CameraInfo
 import android.os.Build
+import com.google.zxing.BarcodeFormat
 import com.journeyapps.barcodescanner.BarcodeCallback
 import com.journeyapps.barcodescanner.BarcodeResult
 import com.journeyapps.barcodescanner.BarcodeView
@@ -17,12 +17,11 @@ import io.flutter.plugin.common.BinaryMessenger
 import io.flutter.plugin.common.MethodCall
 import io.flutter.plugin.common.MethodChannel
 import io.flutter.plugin.platform.PlatformView
-class QRView(messenger: BinaryMessenger, id: Int, private val context: Context) :
+class QRView(messenger: BinaryMessenger, id: Int, private val params: HashMap<String, Any>) :
         PlatformView, MethodChannel.MethodCallHandler {
 
     private var isTorchOn: Boolean = false
     private var barcodeView: BarcodeView? = null
-    private var requestingPermission = false
     private val channel: MethodChannel
 
     init {
@@ -65,89 +64,173 @@ class QRView(messenger: BinaryMessenger, id: Int, private val context: Context)
     }
 
     override fun onMethodCall(call: MethodCall, result: MethodChannel.Result) {
-        when(call.method){
-            "flipCamera" -> {
-                flipCamera()
-            }
-            "toggleFlash" -> {
-                toggleFlash()
-            }
-            "pauseCamera" -> {
-                pauseCamera()
-            }
-            "resumeCamera" -> {
-                resumeCamera()
-            }
+        when(call.method) {
+            "startScan" -> startScan(call.arguments as? List<Int>, result)
+            "stopScan" -> stopScan()
+            "flipCamera" -> flipCamera(result)
+            "toggleFlash" -> toggleFlash(result)
+            "pauseCamera" -> pauseCamera(result)
+            "resumeCamera" -> resumeCamera(result)
+            "requestPermissions" -> checkAndRequestPermission(result)
+            "getCameraInfo" -> getCameraInfo(result)
+            "getFlashInfo" -> getFlashInfo(result)
+            "getSystemFeatures" -> getSystemFeatures(result)
+            else -> result.notImplemented()
         }
     }
 
-    private fun flipCamera() {
-        barcodeView?.pause()
-        val settings = barcodeView?.cameraSettings
+    private fun getCameraInfo(result: MethodChannel.Result) {
+        if (barcodeView == null) {
+            return barCodeViewNotSet(result)
+        }
+        result.success(barcodeView!!.cameraSettings.requestedCameraId)
+    }
+
+    private fun flipCamera(result: MethodChannel.Result) {
+        if (barcodeView == null) {
+            return barCodeViewNotSet(result)
+        }
+        barcodeView!!.pause()
+        val settings = barcodeView!!.cameraSettings
 
-        if(settings?.requestedCameraId == CameraInfo.CAMERA_FACING_FRONT)
+        if(settings.requestedCameraId == CameraInfo.CAMERA_FACING_FRONT)
             settings.requestedCameraId = CameraInfo.CAMERA_FACING_BACK
         else
-            settings?.requestedCameraId = CameraInfo.CAMERA_FACING_FRONT
+            settings.requestedCameraId = CameraInfo.CAMERA_FACING_FRONT
 
-        barcodeView?.cameraSettings = settings
-        barcodeView?.resume()
+        barcodeView!!.cameraSettings = settings
+        barcodeView!!.resume()
+        result.success(settings.requestedCameraId)
     }
 
-    private fun toggleFlash() {
+    private fun getFlashInfo(result: MethodChannel.Result) {
+        if (barcodeView == null) {
+            return barCodeViewNotSet(result)
+        }
+        result.success(isTorchOn)
+    }
+
+    private fun toggleFlash(result: MethodChannel.Result) {
+        if (barcodeView == null) {
+            return barCodeViewNotSet(result)
+        }
+
         if (hasFlash()) {
-            barcodeView?.setTorch(!isTorchOn)
+            barcodeView!!.setTorch(!isTorchOn)
             isTorchOn = !isTorchOn
+            result.success(isTorchOn)
+        } else {
+            result.error("404", "This device doesn't support flash", null)
         }
 
     }
 
-    private fun pauseCamera() {
+    private fun pauseCamera(result: MethodChannel.Result) {
+        if (barcodeView == null) {
+            return barCodeViewNotSet(result)
+        }
         if (barcodeView!!.isPreviewActive) {
-            barcodeView?.pause()
+            barcodeView!!.pause()
         }
+        result.success(true)
     }
 
-    private fun resumeCamera() {
+    private fun resumeCamera(result: MethodChannel.Result) {
+        if (barcodeView == null) {
+            return barCodeViewNotSet(result)
+        }
         if (!barcodeView!!.isPreviewActive) {
-            barcodeView?.resume()
+            barcodeView!!.resume()
         }
+        result.success(true)
     }
 
     private fun hasFlash(): Boolean {
-        return context.packageManager
-                .hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH)
+        return hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH)
+    }
+
+    private fun hasBackCamera(): Boolean {
+        return hasSystemFeature(PackageManager.FEATURE_CAMERA)
+    }
+
+    private fun hasFrontCamera(): Boolean {
+        return hasSystemFeature(PackageManager.FEATURE_CAMERA_FRONT)
+    }
+
+    private fun hasSystemFeature(feature: String): Boolean {
+        return Shared.activity!!.packageManager
+                .hasSystemFeature(feature)
+    }
+
+    private fun barCodeViewNotSet(result: MethodChannel.Result) {
+        result.error("404", "No barcode view found", null)
     }
 
     override fun getView(): View {
         return initBarCodeView()?.apply {
+            if (!hasBackCamera()) {
+                if (!hasFrontCamera()) {
+                    // No camera available!
+                } else {
+                    this.cameraSettings.requestedCameraId = CameraInfo.CAMERA_FACING_FRONT
+                }
+            } else {
+                this.cameraSettings.requestedCameraId = CameraInfo.CAMERA_FACING_BACK
+            }
             resume()
         }!!
     }
 
     private fun initBarCodeView(): BarcodeView? {
         if (barcodeView == null) {
-            barcodeView = createBarCodeView()
+            barcodeView = BarcodeView(Shared.activity)
+            if (params["cameraFacing"] as Int == 1) {
+                barcodeView?.cameraSettings?.requestedCameraId = CameraInfo.CAMERA_FACING_FRONT
+            }
         }
         return barcodeView
     }
 
-    private fun createBarCodeView(): BarcodeView {
-        val barcode = BarcodeView(Shared.activity)
-        barcode.decodeContinuous(
+    private fun startScan(arguments: List<Int>?, result: MethodChannel.Result) {
+        val allowedBarcodeTypes = mutableListOf<BarcodeFormat>()
+        try {
+            arguments?.forEach {
+                allowedBarcodeTypes.add(BarcodeFormat.values()[it])
+            }
+        } catch (e: java.lang.Exception) {
+            result.error(null, null, null)
+        }
+
+        barcodeView?.decodeContinuous(
                 object : BarcodeCallback {
                     override fun barcodeResult(result: BarcodeResult) {
-                        val code = mapOf(
-                                "code" to result.text,
-                                "type" to result.barcodeFormat.name,
-                                "rawBytes" to result.rawBytes)
-                        channel.invokeMethod("onRecognizeQR", code)
+                        if (allowedBarcodeTypes.size == 0 || allowedBarcodeTypes.contains(result.barcodeFormat)) {
+                            val code = mapOf(
+                                    "code" to result.text,
+                                    "type" to result.barcodeFormat.name,
+                                    "rawBytes" to result.rawBytes)
+                            channel.invokeMethod("onRecognizeQR", code)
+                        }
+
                     }
 
                     override fun possibleResultPoints(resultPoints: List<ResultPoint>) {}
                 }
         )
-        return barcode
+    }
+
+    private fun stopScan() {
+        barcodeView?.stopDecoding()
+    }
+
+    private fun getSystemFeatures(result: MethodChannel.Result) {
+        try {
+            result.success(mapOf("hasFrontCamera" to hasFrontCamera(),
+                    "hasBackCamera" to hasBackCamera(), "hasFlash" to hasFlash(),
+                    "activeCamera" to barcodeView?.cameraSettings?.requestedCameraId))
+        } catch (e: Exception) {
+            result.error(null, null, null)
+        }
     }
 
     private fun hasCameraPermission(): Boolean {
@@ -156,29 +239,16 @@ class QRView(messenger: BinaryMessenger, id: Int, private val context: Context)
     }
 
     private fun checkAndRequestPermission(result: MethodChannel.Result?) {
-        if (Shared.cameraPermissionContinuation != null) {
-            result?.error("cameraPermission", "Camera permission request ongoing", null)
-        }
-
-        Shared.cameraPermissionContinuation = Runnable {
-            Shared.cameraPermissionContinuation = null
-            if (!hasCameraPermission()) {
-                result?.error(
-                        "cameraPermission", "MediaRecorderCamera permission not granted", null)
-                return@Runnable
-            }
-        }
-
-        requestingPermission = false
-        if (hasCameraPermission()) {
-            Shared.cameraPermissionContinuation?.run()
-        } else {
-            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
-                requestingPermission = true
+        when {
+            hasCameraPermission() -> result?.success(true)
+            Build.VERSION.SDK_INT >= Build.VERSION_CODES.M -> {
                 Shared.activity?.requestPermissions(
                         arrayOf(Manifest.permission.CAMERA),
                         Shared.CAMERA_REQUEST_ID)
             }
+            else -> {
+                result?.error("cameraPermission", "Platform Version to low for camera permission check", null)
+            }
         }
     }
 }

android/src/main/kotlin/net/touchcapture/qr/flutterqr/QRViewFactory.kt

@@ -10,8 +10,9 @@ import io.flutter.plugin.platform.PlatformViewFactory
 class QRViewFactory(private val messenger: BinaryMessenger) :
         PlatformViewFactory(StandardMessageCodec.INSTANCE) {
 
-    override fun create(context: Context, id: Int, obj: Any?): PlatformView {
-        return QRView(messenger, id, context)
+    override fun create(context: Context, id: Int, args: Any?): PlatformView {
+        val params = args as HashMap<String, Any>
+        return QRView(messenger, id, params)
     }
 
 }

android/src/main/kotlin/net/touchcapture/qr/flutterqr/Shared.kt

@@ -5,5 +5,4 @@ import android.app.Activity
 object Shared {
     const val CAMERA_REQUEST_ID = 513469796
     var activity: Activity? = null
-    var cameraPermissionContinuation: Runnable? = null
 }

example/.gitignore

@@ -9,6 +9,7 @@
 .buildlog/
 .history
 .svn/
+.last_build_id
 
 # IntelliJ related
 *.iml

example/ios/Runner.xcodeproj/project.pbxproj

@@ -9,11 +9,11 @@
 /* Begin PBXBuildFile section */
 		1498D2341E8E89220040F4C2 /* GeneratedPluginRegistrant.m in Sources */ = {isa = PBXBuildFile; fileRef = 1498D2331E8E89220040F4C2 /* GeneratedPluginRegistrant.m */; };
 		3B3967161E833CAA004F5970 /* AppFrameworkInfo.plist in Resources */ = {isa = PBXBuildFile; fileRef = 3B3967151E833CAA004F5970 /* AppFrameworkInfo.plist */; };
+		4FA3805501F593094264678B /* Pods_Runner.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 75B64521967C76C845268E71 /* Pods_Runner.framework */; };
 		74858FAF1ED2DC5600515810 /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 74858FAE1ED2DC5600515810 /* AppDelegate.swift */; };
 		97C146FC1CF9000F007C117D /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 97C146FA1CF9000F007C117D /* Main.storyboard */; };
 		97C146FE1CF9000F007C117D /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 97C146FD1CF9000F007C117D /* Assets.xcassets */; };
 		97C147011CF9000F007C117D /* LaunchScreen.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 97C146FF1CF9000F007C117D /* LaunchScreen.storyboard */; };
-		F50BD2AA150CE43D961DBB69 /* Pods_Runner.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C211BF4383BB3311CB0313D6 /* Pods_Runner.framework */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXCopyFilesBuildPhase section */
@@ -30,15 +30,14 @@
 /* End PBXCopyFilesBuildPhase section */
 
 /* Begin PBXFileReference section */
-		11A772D5271EABFB7473B52C /* 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>"; };
+		08F42BD28C1585A831B4FDA2 /* 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>"; };
 		1498D2321E8E86230040F4C2 /* GeneratedPluginRegistrant.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = GeneratedPluginRegistrant.h; sourceTree = "<group>"; };
 		1498D2331E8E89220040F4C2 /* GeneratedPluginRegistrant.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GeneratedPluginRegistrant.m; sourceTree = "<group>"; };
 		3B3967151E833CAA004F5970 /* AppFrameworkInfo.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; name = AppFrameworkInfo.plist; path = Flutter/AppFrameworkInfo.plist; sourceTree = "<group>"; };
-		4D86354DC939411D3F7E41EA /* 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>"; };
 		74858FAD1ED2DC5600515810 /* Runner-Bridging-Header.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "Runner-Bridging-Header.h"; sourceTree = "<group>"; };
 		74858FAE1ED2DC5600515810 /* AppDelegate.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
+		75B64521967C76C845268E71 /* Pods_Runner.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_Runner.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		7AFA3C8E1D35360C0083082E /* Release.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; name = Release.xcconfig; path = Flutter/Release.xcconfig; sourceTree = "<group>"; };
-		96DCE88542EFC8C39614159F /* 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>"; };
 		9740EEB21CF90195004384FC /* Debug.xcconfig */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.xcconfig; name = Debug.xcconfig; path = Flutter/Debug.xcconfig; sourceTree = "<group>"; };
 		9740EEB31CF90195004384FC /* Generated.xcconfig */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.xcconfig; name = Generated.xcconfig; path = Flutter/Generated.xcconfig; sourceTree = "<group>"; };
 		97C146EE1CF9000F007C117D /* Runner.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = Runner.app; sourceTree = BUILT_PRODUCTS_DIR; };
@@ -46,7 +45,8 @@
 		97C146FD1CF9000F007C117D /* Assets.xcassets */ = {isa = PBXFileReference; lastKnownFileType = folder.assetcatalog; path = Assets.xcassets; sourceTree = "<group>"; };
 		97C147001CF9000F007C117D /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.storyboard; name = Base; path = Base.lproj/LaunchScreen.storyboard; sourceTree = "<group>"; };
 		97C147021CF9000F007C117D /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
-		C211BF4383BB3311CB0313D6 /* Pods_Runner.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_Runner.framework; sourceTree = BUILT_PRODUCTS_DIR; };
+		DB8991B7B046D94B2E68CEAD /* 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>"; };
+		EF8A0739582463E296AD6CB1 /* 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>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -54,21 +54,13 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				F50BD2AA150CE43D961DBB69 /* Pods_Runner.framework in Frameworks */,
+				4FA3805501F593094264678B /* Pods_Runner.framework in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
 /* End PBXFrameworksBuildPhase section */
 
 /* Begin PBXGroup section */
-		509AC3E235E568B6DDAAEC7D /* Frameworks */ = {
-			isa = PBXGroup;
-			children = (
-				C211BF4383BB3311CB0313D6 /* Pods_Runner.framework */,
-			);
-			name = Frameworks;
-			sourceTree = "<group>";
-		};
 		9740EEB11CF90186004384FC /* Flutter */ = {
 			isa = PBXGroup;
 			children = (
@@ -87,7 +79,7 @@
 				97C146F01CF9000F007C117D /* Runner */,
 				97C146EF1CF9000F007C117D /* Products */,
 				D7C58E57CAF69D9A14CC212F /* Pods */,
-				509AC3E235E568B6DDAAEC7D /* Frameworks */,
+				AF031A634C9742F16BF4F89A /* Frameworks */,
 			);
 			sourceTree = "<group>";
 		};
@@ -122,12 +114,20 @@
 			name = "Supporting Files";
 			sourceTree = "<group>";
 		};
+		AF031A634C9742F16BF4F89A /* Frameworks */ = {
+			isa = PBXGroup;
+			children = (
+				75B64521967C76C845268E71 /* Pods_Runner.framework */,
+			);
+			name = Frameworks;
+			sourceTree = "<group>";
+		};
 		D7C58E57CAF69D9A14CC212F /* Pods */ = {
 			isa = PBXGroup;
 			children = (
-				4D86354DC939411D3F7E41EA /* Pods-Runner.debug.xcconfig */,
-				11A772D5271EABFB7473B52C /* Pods-Runner.release.xcconfig */,
-				96DCE88542EFC8C39614159F /* Pods-Runner.profile.xcconfig */,
+				DB8991B7B046D94B2E68CEAD /* Pods-Runner.debug.xcconfig */,
+				EF8A0739582463E296AD6CB1 /* Pods-Runner.release.xcconfig */,
+				08F42BD28C1585A831B4FDA2 /* Pods-Runner.profile.xcconfig */,
 			);
 			path = Pods;
 			sourceTree = "<group>";
@@ -139,14 +139,14 @@
 			isa = PBXNativeTarget;
 			buildConfigurationList = 97C147051CF9000F007C117D /* Build configuration list for PBXNativeTarget "Runner" */;
 			buildPhases = (
-				854A11C1BE2493D5A6BD85DB /* [CP] Check Pods Manifest.lock */,
+				7BEA526A4A0DFAAC4945EC09 /* [CP] Check Pods Manifest.lock */,
 				9740EEB61CF901F6004384FC /* Run Script */,
 				97C146EA1CF9000F007C117D /* Sources */,
 				97C146EB1CF9000F007C117D /* Frameworks */,
 				97C146EC1CF9000F007C117D /* Resources */,
 				9705A1C41CF9048500538489 /* Embed Frameworks */,
 				3B06AD1E1E4923F5004D2608 /* Thin Binary */,
-				FDE6A3C9913AC5840FF42544 /* [CP] Embed Pods Frameworks */,
+				8DB6578C615972DBF2DFAA0D /* [CP] Embed Pods Frameworks */,
 			);
 			buildRules = (
 			);
@@ -168,7 +168,7 @@
 				TargetAttributes = {
 					97C146ED1CF9000F007C117D = {
 						CreatedOnToolsVersion = 7.3.1;
-						DevelopmentTeam = 5LSCTACHT8;
+						DevelopmentTeam = RCH2VG82SH;
 						LastSwiftMigration = 1020;
 						ProvisioningStyle = Automatic;
 					};
@@ -221,7 +221,7 @@
 			shellPath = /bin/sh;
 			shellScript = "/bin/sh \"$FLUTTER_ROOT/packages/flutter_tools/bin/xcode_backend.sh\" embed_and_thin";
 		};
-		854A11C1BE2493D5A6BD85DB /* [CP] Check Pods Manifest.lock */ = {
+		7BEA526A4A0DFAAC4945EC09 /* [CP] Check Pods Manifest.lock */ = {
 			isa = PBXShellScriptBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
@@ -243,41 +243,41 @@
 			shellScript = "diff \"${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;
 		};
-		9740EEB61CF901F6004384FC /* Run Script */ = {
+		8DB6578C615972DBF2DFAA0D /* [CP] Embed Pods Frameworks */ = {
 			isa = PBXShellScriptBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
 			);
 			inputPaths = (
+				"${PODS_ROOT}/Target Support Files/Pods-Runner/Pods-Runner-frameworks.sh",
+				"${PODS_ROOT}/../Flutter/Flutter.framework",
+				"${BUILT_PRODUCTS_DIR}/MTBBarcodeScanner/MTBBarcodeScanner.framework",
+				"${BUILT_PRODUCTS_DIR}/qr_code_scanner/qr_code_scanner.framework",
 			);
-			name = "Run Script";
+			name = "[CP] Embed Pods Frameworks";
 			outputPaths = (
+				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/Flutter.framework",
+				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/MTBBarcodeScanner.framework",
+				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/qr_code_scanner.framework",
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
-			shellScript = "/bin/sh \"$FLUTTER_ROOT/packages/flutter_tools/bin/xcode_backend.sh\" build";
+			shellScript = "\"${PODS_ROOT}/Target Support Files/Pods-Runner/Pods-Runner-frameworks.sh\"\n";
+			showEnvVarsInLog = 0;
 		};
-		FDE6A3C9913AC5840FF42544 /* [CP] Embed Pods Frameworks */ = {
+		9740EEB61CF901F6004384FC /* Run Script */ = {
 			isa = PBXShellScriptBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
 			);
 			inputPaths = (
-				"${PODS_ROOT}/Target Support Files/Pods-Runner/Pods-Runner-frameworks.sh",
-				"${PODS_ROOT}/../Flutter/Flutter.framework",
-				"${BUILT_PRODUCTS_DIR}/MTBBarcodeScanner/MTBBarcodeScanner.framework",
-				"${BUILT_PRODUCTS_DIR}/qr_code_scanner/qr_code_scanner.framework",
 			);
-			name = "[CP] Embed Pods Frameworks";
+			name = "Run Script";
 			outputPaths = (
-				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/Flutter.framework",
-				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/MTBBarcodeScanner.framework",
-				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/qr_code_scanner.framework",
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
-			shellScript = "\"${PODS_ROOT}/Target Support Files/Pods-Runner/Pods-Runner-frameworks.sh\"\n";
-			showEnvVarsInLog = 0;
+			shellScript = "/bin/sh \"$FLUTTER_ROOT/packages/flutter_tools/bin/xcode_backend.sh\" build";
 		};
 /* End PBXShellScriptBuildPhase section */
 
@@ -372,7 +372,7 @@
 				CODE_SIGN_IDENTITY = "iPhone Developer";
 				CODE_SIGN_STYLE = Automatic;
 				CURRENT_PROJECT_VERSION = "$(FLUTTER_BUILD_NUMBER)";
-				DEVELOPMENT_TEAM = 5LSCTACHT8;
+				DEVELOPMENT_TEAM = RCH2VG82SH;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
 					"$(inherited)",
@@ -510,7 +510,7 @@
 				CODE_SIGN_IDENTITY = "iPhone Developer";
 				CODE_SIGN_STYLE = Automatic;
 				CURRENT_PROJECT_VERSION = "$(FLUTTER_BUILD_NUMBER)";
-				DEVELOPMENT_TEAM = 5LSCTACHT8;
+				DEVELOPMENT_TEAM = RCH2VG82SH;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
 					"$(inherited)",
@@ -541,7 +541,7 @@
 				CODE_SIGN_IDENTITY = "iPhone Developer";
 				CODE_SIGN_STYLE = Automatic;
 				CURRENT_PROJECT_VERSION = "$(FLUTTER_BUILD_NUMBER)";
-				DEVELOPMENT_TEAM = 5LSCTACHT8;
+				DEVELOPMENT_TEAM = RCH2VG82SH;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
 					"$(inherited)",

example/lib/main.dart

@@ -6,11 +6,6 @@ import 'package:qr_code_scanner/qr_code_scanner.dart';
 
 void main() => runApp(MaterialApp(home: QRViewExample()));
 
-const flashOn = 'FLASH ON';
-const flashOff = 'FLASH OFF';
-const frontCamera = 'FRONT CAMERA';
-const backCamera = 'BACK CAMERA';
-
 class QRViewExample extends StatefulWidget {
   const QRViewExample({
     Key key,
@@ -22,8 +17,6 @@ class QRViewExample extends StatefulWidget {
 
 class _QRViewExampleState extends State<QRViewExample> {
   Barcode result;
-  var flashState = flashOn;
-  var cameraState = frontCamera;
   QRViewController controller;
   final GlobalKey qrKey = GlobalKey(debugLabel: 'QR');
 
@@ -64,44 +57,33 @@ class _QRViewExampleState extends State<QRViewExample> {
                       Container(
                         margin: EdgeInsets.all(8),
                         child: RaisedButton(
-                          onPressed: () {
-                            if (controller != null) {
-                              controller.toggleFlash();
-                              if (_isFlashOn(flashState)) {
-                                setState(() {
-                                  flashState = flashOff;
-                                });
-                              } else {
-                                setState(() {
-                                  flashState = flashOn;
-                                });
-                              }
-                            }
-                          },
-                          child:
-                              Text(flashState, style: TextStyle(fontSize: 20)),
-                        ),
+                            onPressed: () => setState(() {
+                                  controller?.toggleFlash();
+                                }),
+                            child: FutureBuilder(
+                              future: controller?.getFlashStatus(),
+                              builder: (context, snapshot) {
+                                return Text('Flash: ${snapshot.data}');
+                              },
+                            )),
                       ),
                       Container(
                         margin: EdgeInsets.all(8),
                         child: RaisedButton(
-                          onPressed: () {
-                            if (controller != null) {
-                              controller.flipCamera();
-                              if (_isBackCamera(cameraState)) {
-                                setState(() {
-                                  cameraState = frontCamera;
-                                });
-                              } else {
-                                setState(() {
-                                  cameraState = backCamera;
-                                });
-                              }
-                            }
-                          },
-                          child:
-                              Text(cameraState, style: TextStyle(fontSize: 20)),
-                        ),
+                            onPressed: () => setState(() {
+                                  controller?.flipCamera();
+                                }),
+                            child: FutureBuilder(
+                              future: controller?.getCameraInfo(),
+                              builder: (context, snapshot) {
+                                if (snapshot.data != null) {
+                                  return Text(
+                                      'Camera facing ${describeEnum(snapshot.data)}');
+                                } else {
+                                  return Text('loading');
+                                }
+                              },
+                            )),
                       )
                     ],
                   ),
@@ -138,14 +120,6 @@ class _QRViewExampleState extends State<QRViewExample> {
     );
   }
 
-  bool _isFlashOn(String current) {
-    return flashOn == current;
-  }
-
-  bool _isBackCamera(String current) {
-    return backCamera == current;
-  }
-
   Widget _buildQrView(BuildContext context) {
     // For this example we check how width or tall the device is and change the scanArea and overlay accordingly.
     var scanArea = (MediaQuery.of(context).size.width < 400 ||
@@ -154,29 +128,25 @@ class _QRViewExampleState extends State<QRViewExample> {
         : 300.0;
     // To ensure the Scanner view is properly sizes after rotation
     // we need to listen for Flutter SizeChanged notification and update controller
-    return NotificationListener<SizeChangedLayoutNotification>(
-        onNotification: (notification) {
-          Future.microtask(
-              () => controller?.updateDimensions(qrKey, scanArea: scanArea));
-          return false;
-        },
-        child: SizeChangedLayoutNotifier(
-            key: const Key('qr-size-notifier'),
-            child: QRView(
-              key: qrKey,
-              onQRViewCreated: _onQRViewCreated,
-              overlay: QrScannerOverlayShape(
-                borderColor: Colors.red,
-                borderRadius: 10,
-                borderLength: 30,
-                borderWidth: 10,
-                cutOutSize: scanArea,
-              ),
-            )));
+    return QRView(
+      key: qrKey,
+      cameraFacing: CameraFacing.front,
+      onQRViewCreated: _onQRViewCreated,
+      formatsAllowed: [BarcodeFormat.qrcode],
+      overlay: QrScannerOverlayShape(
+        borderColor: Colors.red,
+        borderRadius: 10,
+        borderLength: 30,
+        borderWidth: 10,
+        cutOutSize: scanArea,
+      ),
+    );
   }
 
   void _onQRViewCreated(QRViewController controller) {
-    this.controller = controller;
+    setState(() {
+      this.controller = controller;
+    });
     controller.scannedDataStream.listen((scanData) {
       setState(() {
         result = scanData;

example/pubspec.yaml

@@ -3,7 +3,7 @@ description: Demonstrates how to use the flutter_qr plugin.
 publish_to: 'none'
 
 environment:
-  sdk: ">=2.3.0 <3.0.0"
+  sdk: ">=2.6.0 <3.0.0"
 
 dependencies:
   flutter:

ios/Classes/QRView.swift

@@ -13,75 +13,56 @@ public class QRView:NSObject,FlutterPlatformView {
     var scanner: MTBBarcodeScanner?
     var registrar: FlutterPluginRegistrar
     var channel: FlutterMethodChannel
+    var cameraFacing: MTBCamera
     
-    public init(withFrame frame: CGRect, withRegistrar registrar: FlutterPluginRegistrar, withId id: Int64){
+    var QRCodeTypes = [
+          0: AVMetadataObject.ObjectType.aztec,
+          2: AVMetadataObject.ObjectType.code39,
+          3: AVMetadataObject.ObjectType.code93,
+          4: AVMetadataObject.ObjectType.code128,
+          5: AVMetadataObject.ObjectType.dataMatrix,
+          6: AVMetadataObject.ObjectType.ean8,
+          7: AVMetadataObject.ObjectType.ean13,
+          8: AVMetadataObject.ObjectType.interleaved2of5,
+          10: AVMetadataObject.ObjectType.pdf417,
+          11: AVMetadataObject.ObjectType.qr,
+          15: AVMetadataObject.ObjectType.upce
+         ]
+    
+    public init(withFrame frame: CGRect, withRegistrar registrar: FlutterPluginRegistrar, withId id: Int64, params: Dictionary<String, Any>){
         self.registrar = registrar
         previewView = UIView(frame: frame)
+        cameraFacing = MTBCamera.init(rawValue: UInt(Int(params["cameraFacing"] as! Double))) ?? MTBCamera.back
         channel = FlutterMethodChannel(name: "net.touchcapture.qr.flutterqr/qrview_\(id)", binaryMessenger: registrar.messenger())
     }
     
-    func isCameraAvailable(success: Bool) -> Void {
-        if success {
-            do {
-                try scanner?.startScanning(resultBlock: { [weak self] codes in
-                    if let codes = codes {
-                        for code in codes {
-                            var typeString: String;
-                            switch(code.type) {
-                                case AVMetadataObject.ObjectType.aztec:
-                                   typeString = "AZTEC"
-                                case AVMetadataObject.ObjectType.code39:
-                                    typeString = "CODE_39"
-                                case AVMetadataObject.ObjectType.code93:
-                                    typeString = "CODE_93"
-                                case AVMetadataObject.ObjectType.code128:
-                                    typeString = "CODE_128"
-                                case AVMetadataObject.ObjectType.dataMatrix:
-                                    typeString = "DATA_MATRIX"
-                                case AVMetadataObject.ObjectType.ean8:
-                                    typeString = "EAN_8"
-                                case AVMetadataObject.ObjectType.ean13:
-                                    typeString = "EAN_13"
-                                case AVMetadataObject.ObjectType.itf14:
-                                    typeString = "ITF"
-                                case AVMetadataObject.ObjectType.pdf417:
-                                    typeString = "PDF_417"
-                                case AVMetadataObject.ObjectType.qr:
-                                    typeString = "QR_CODE"
-                                case AVMetadataObject.ObjectType.upce:
-                                    typeString = "UPC_E"
-                                default:
-                                    return
-                            }
-                            guard let stringValue = code.stringValue else { continue }
-                            let result = ["code": stringValue, "type": typeString]
-                            self?.channel.invokeMethod("onRecognizeQR", arguments: result)
-                        }
-                    }
-                })
-            } catch {
-                NSLog("Unable to start scanning")
-            }
-        } else {
-            UIAlertView(title: "Scanning Unavailable", message: "This app does not have permission to access the camera", delegate: nil, cancelButtonTitle: nil, otherButtonTitles: "Ok").show()
-        }
+    deinit {
+        scanner?.stopScanning()
     }
     
     public func view() -> UIView {
         channel.setMethodCallHandler({
-            [weak self] (call: FlutterMethodCall, result: FlutterResult) -> Void in
+            [weak self] (call: FlutterMethodCall, result: @escaping FlutterResult) -> Void in
             switch(call.method){
                 case "setDimensions":
                     let arguments = call.arguments as! Dictionary<String, Double>
                     self?.setDimensions(width: arguments["width"] ?? 0, height: arguments["height"] ?? 0, scanArea: arguments["scanArea"] ?? 0)
+                case "startScan":
+                    self?.startScan(call.arguments as! Array<Int>, result)
                 case "flipCamera":
-                    self?.flipCamera()
+                    self?.flipCamera(result)
                 case "toggleFlash":
-                    self?.toggleFlash()
+                    self?.toggleFlash(result)
                 case "pauseCamera":
-                    self?.pauseCamera()
+                    self?.pauseCamera(result)
                 case "resumeCamera":
-                    self?.resumeCamera()
+                    self?.resumeCamera(result)
+                case "getCameraInfo":
+                    self?.getCameraInfo(result)
+                case "getFlashInfo":
+                    self?.getFlashInfo(result)
+                case "getSystemFeatures":
+                    self?.getSystemFeatures(result)
                 default:
                     result(FlutterMethodNotImplemented)
                     return
@@ -106,41 +87,162 @@ public class QRView:NSObject,FlutterPlatformView {
                     self.scanner?.scanRect = CGRect(x: Double(midX) - (scanArea / 2), y: Double(midY) - (scanArea / 2), width: scanArea, height: scanArea)
                 }
             }
+        }
+    }
+    
+    func startScan(_ arguments: Array<Int>, _ result: @escaping FlutterResult) -> Void {
+        scanner = MTBBarcodeScanner(previewView: previewView)
+        
+        var allowedBarcodeTypes: Array<AVMetadataObject.ObjectType> = []
+        arguments.forEach { arg in
+            allowedBarcodeTypes.append( QRCodeTypes[arg]!)
+        }
 
-
-            MTBBarcodeScanner.requestCameraPermission(success: isCameraAvailable)
+        MTBBarcodeScanner.requestCameraPermission(success: { permissionGranted in
+            if permissionGranted {
+                do {
+                    try self.scanner?.startScanning(with: self.cameraFacing, resultBlock: { [weak self] codes in
+                        if let codes = codes {
+                            for code in codes {
+                                var typeString: String;
+                                switch(code.type) {
+                                    case AVMetadataObject.ObjectType.aztec:
+                                       typeString = "AZTEC"
+                                    case AVMetadataObject.ObjectType.code39:
+                                        typeString = "CODE_39"
+                                    case AVMetadataObject.ObjectType.code93:
+                                        typeString = "CODE_93"
+                                    case AVMetadataObject.ObjectType.code128:
+                                        typeString = "CODE_128"
+                                    case AVMetadataObject.ObjectType.dataMatrix:
+                                        typeString = "DATA_MATRIX"
+                                    case AVMetadataObject.ObjectType.ean8:
+                                        typeString = "EAN_8"
+                                    case AVMetadataObject.ObjectType.ean13:
+                                        typeString = "EAN_13"
+                                    case AVMetadataObject.ObjectType.itf14:
+                                        typeString = "ITF"
+                                    case AVMetadataObject.ObjectType.pdf417:
+                                        typeString = "PDF_417"
+                                    case AVMetadataObject.ObjectType.qr:
+                                        typeString = "QR_CODE"
+                                    case AVMetadataObject.ObjectType.upce:
+                                        typeString = "UPC_E"
+                                    default:
+                                        return
+                                }
+                                guard let stringValue = code.stringValue else { continue }
+                               let result = ["code": stringValue, "type": typeString]
+                                if allowedBarcodeTypes.count == 0 || allowedBarcodeTypes.contains(code.type) {
+                                    self?.channel.invokeMethod("onRecognizeQR", arguments: result)
+                                }
+                                
+                            }
+                        }
+                    })
+                } catch {
+                    let error = FlutterError(code: "unknown-error", message: "Unable to start scanning", details: nil)
+                    result(error)
+                }
+            } else {
+                let error = FlutterError(code: "cameraPermission", message: "Permission denied to access the camera", details: nil)
+                result(error)
+            }
+        })
+    }
+    
+    func stopScan(){
+        if let sc: MTBBarcodeScanner = scanner {
+            if sc.isScanning() {
+                sc.stopScanning()
+            }
+        }
+    }
+    
+    func getCameraInfo(_ result: @escaping FlutterResult) -> Void {
+        if let sc: MTBBarcodeScanner = scanner {
+            result(sc.camera.rawValue)
+        } else {
+            let error = FlutterError(code: "cameraInformationError", message: "Could not get camera information", details: nil)
+            result(error)
         }
     }
     
-    func flipCamera(){
+    func flipCamera(_ result: @escaping FlutterResult){
         if let sc: MTBBarcodeScanner = scanner {
             if sc.hasOppositeCamera() {
                 sc.flipCamera()
             }
+            return result(sc.camera.rawValue)
+        }
+        return result(FlutterError(code: "404", message: "No barcode scanner found", details: nil))
+    }
+    
+    func getFlashInfo(_ result: @escaping FlutterResult) -> Void {
+        if let sc: MTBBarcodeScanner = scanner {
+            result(sc.torchMode.rawValue != 0)
+        } else {
+            let error = FlutterError(code: "cameraInformationError", message: "Could not get flash information", details: nil)
+            result(error)
         }
     }
     
-    func toggleFlash(){
+    func toggleFlash(_ result: @escaping FlutterResult){
         if let sc: MTBBarcodeScanner = scanner {
             if sc.hasTorch() {
                 sc.toggleTorch()
+                return result(sc.torchMode == MTBTorchMode(rawValue: 1))
             }
+            return result(FlutterError(code: "404", message: "This device doesn\'t support flash", details: nil))
         }
+        return result(FlutterError(code: "404", message: "No barcode scanner found", details: nil))
     }
     
-    func pauseCamera() {
+    func pauseCamera(_ result: @escaping FlutterResult) {
         if let sc: MTBBarcodeScanner = scanner {
             if sc.isScanning() {
                 sc.freezeCapture()
             }
+            return result(true)
         }
+        return result(FlutterError(code: "404", message: "No barcode scanner found", details: nil))
     }
     
-    func resumeCamera() {
+    func resumeCamera(_ result: @escaping FlutterResult) {
         if let sc: MTBBarcodeScanner = scanner {
             if !sc.isScanning() {
                 sc.unfreezeCapture()
             }
+            return result(true)
+        }
+        return result(FlutterError(code: "404", message: "No barcode scanner found", details: nil))
+    }
+
+    func getSystemFeatures(_ result: @escaping FlutterResult) -> Void {
+        if let sc: MTBBarcodeScanner = scanner {
+            var hasBackCameraVar = false
+            var hasFrontCameraVar = false
+            let camera = sc.camera
+
+            if(camera == MTBCamera(rawValue: 0)){
+                hasBackCameraVar = true
+                if sc.hasOppositeCamera() {
+                    hasFrontCameraVar = true
+                }
+            }else{
+                hasFrontCameraVar = true
+                if sc.hasOppositeCamera() {
+                    hasBackCameraVar = true
+                }
+            }
+            return result([
+                "hasFrontCamera": hasFrontCameraVar,
+                "hasBackCamera": hasBackCameraVar,
+                "hasFlash": sc.hasTorch(),
+                "activeCamera": camera.rawValue
+            ])
         }
+        return result(FlutterError(code: "404", message: nil, details: nil))
     }
-}
+
+ }

ios/Classes/QRViewFactory.swift

@@ -17,8 +17,8 @@ public class QRViewFactory: NSObject, FlutterPlatformViewFactory {
     }
     
     public func create(withFrame frame: CGRect, viewIdentifier viewId: Int64, arguments args: Any?) -> FlutterPlatformView {
-        let dictionary =  args as! Dictionary<String, Double>
-        return QRView(withFrame: CGRect(x: 0, y: 0, width: dictionary["width"] ?? 0, height: dictionary["height"] ?? 0), withRegistrar: registrar!,withId: viewId)
+        let params = args as! Dictionary<String, Double>
+        return QRView(withFrame: frame, withRegistrar: registrar!,withId: viewId, params: params)
     }
     
     public func createArgsCodec() -> FlutterMessageCodec & NSObjectProtocol {

lib/qr_code_scanner.dart

@@ -1,2 +1,7 @@
 export 'src/qr_code_scanner.dart';
 export 'src/qr_scanner_overlay_shape.dart';
+export 'src/types/barcode.dart';
+export 'src/types/barcode_format.dart';
+export 'src/types/camera.dart';
+export 'src/types/camera_exception.dart';
+export 'src/types/features.dart';

lib/src/qr_code_scanner.dart

@@ -3,138 +3,107 @@ import 'dart:async';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
-import 'package:qr_code_scanner/qr_code_scanner.dart';
 
-typedef QRViewCreatedCallback = void Function(QRViewController);
-
-enum BarcodeFormat {
-  /// Aztec 2D barcode format.
-  aztec,
-
-  /// CODABAR 1D format.
-  codabar,
-
-  /// Code 39 1D format.
-  code39,
-
-  /// Code 93 1D format.
-  code93,
-
-  /// Code 128 1D format.
-  code128,
-
-  /// Data Matrix 2D barcode format.
-  dataMatrix,
-
-  /// EAN-8 1D format.
-  ean8,
-
-  /// EAN-13 1D format.
-  ean13,
-
-  /// ITF (Interleaved Two of Five) 1D format.
-  itf,
-
-  /// MaxiCode 2D barcode format.
-  maxicode,
-
-  /// PDF417 format.
-  pdf417,
-
-  /// QR Code 2D barcode format.
-  qrcode,
-
-  /// RSS 14
-  rss14,
-
-  /// RSS EXPANDED
-  rssExpanded,
-
-  /// UPC-A 1D format.
-  upcA,
+import 'qr_scanner_overlay_shape.dart';
+import 'types/barcode.dart';
+import 'types/barcode_format.dart';
+import 'types/camera.dart';
+import 'types/camera_exception.dart';
+import 'types/features.dart';
 
-  /// UPC-E 1D format.
-  upcE,
-
-  /// UPC/EAN extension format. Not a stand-alone format.
-  upcEanExtension
-}
-
-const _formatNames = <String, BarcodeFormat>{
-  'AZTEC': BarcodeFormat.aztec,
-  'CODABAR': BarcodeFormat.codabar,
-  'CODE_39': BarcodeFormat.code39,
-  'CODE_93': BarcodeFormat.code93,
-  'CODE_128': BarcodeFormat.code128,
-  'DATA_MATRIX': BarcodeFormat.dataMatrix,
-  'EAN_8': BarcodeFormat.ean8,
-  'EAN_13': BarcodeFormat.ean13,
-  'ITF': BarcodeFormat.itf,
-  'MAXICODE': BarcodeFormat.maxicode,
-  'PDF_417': BarcodeFormat.pdf417,
-  'QR_CODE': BarcodeFormat.qrcode,
-  'RSS_14': BarcodeFormat.rss14,
-  'RSS_EXPANDED': BarcodeFormat.rssExpanded,
-  'UPC_A': BarcodeFormat.upcA,
-  'UPC_E': BarcodeFormat.upcE,
-  'UPC_EAN_EXTENSION': BarcodeFormat.upcEanExtension,
-};
-
-class Barcode {
-  Barcode(this.code, this.format, this.rawBytes);
-
-  final String code;
-  final BarcodeFormat format;
-
-  /// Raw bytes are only supported by Android.
-  final List<int> rawBytes;
-}
+typedef QRViewCreatedCallback = void Function(QRViewController);
+typedef PermissionSetCallback = void Function(QRViewController, bool);
 
+/// The [QRView] is the view where the camera
+/// and the barcode scanner gets displayed.
 class QRView extends StatefulWidget {
   const QRView({
     @required Key key,
     @required this.onQRViewCreated,
     this.overlay,
     this.overlayMargin = EdgeInsets.zero,
+    this.cameraFacing = CameraFacing.back,
+    this.onPermissionSet,
+    this.formatsAllowed,
   })  : assert(key != null),
         assert(onQRViewCreated != null),
         super(key: key);
 
+  /// [onQRViewCreated] gets called when the view is created
   final QRViewCreatedCallback onQRViewCreated;
 
+  /// Use [overlay] to provide an overlay for the view.
+  /// This can be used to create a certain scan area.
   final ShapeBorder overlay;
+
+  /// Use [overlayMargin] to provide a margin to [overlay]
   final EdgeInsetsGeometry overlayMargin;
 
+  /// Set which camera to use on startup.
+  ///
+  /// [cameraFacing] can either be CameraFacing.front or CameraFacing.back.
+  /// Defaults to CameraFacing.back
+  final CameraFacing cameraFacing;
+
+  /// Calls the provided [onPermissionSet] callback when the permission is set.
+  final PermissionSetCallback onPermissionSet;
+
+  /// Use [formatsAllowed] to specify which formats needs to be scanned.
+  final List<BarcodeFormat> formatsAllowed;
+
   @override
   State<StatefulWidget> createState() => _QRViewState();
 }
 
 class _QRViewState extends State<QRView> {
+  var _channel;
+
   @override
   Widget build(BuildContext context) {
+    return NotificationListener(
+      onNotification: onNotification,
+      child: SizeChangedLayoutNotifier(
+        child: (widget.overlay != null)
+            ? _getPlatformQrViewWithOverlay()
+            : _getPlatformQrView(),
+      ),
+    );
+  }
+
+  bool onNotification(notification) {
+    Future.microtask(() => {
+          QRViewController.updateDimensions(widget.key, _channel,
+              scanArea: widget.overlay != null
+                  ? (widget.overlay as QrScannerOverlayShape).cutOutSize
+                  : 0.0)
+        });
+    return false;
+  }
+
+  Widget _getPlatformQrViewWithOverlay() {
     return Stack(
       children: [
-        _getPlatformQrView(widget.key),
-        if (widget.overlay != null)
-          Container(
-            padding: widget.overlayMargin,
-            decoration: ShapeDecoration(
-              shape: widget.overlay,
-            ),
-          )
-        else
-          Container(),
+        _getPlatformQrView(),
+        Container(
+          padding: widget.overlayMargin,
+          decoration: ShapeDecoration(
+            shape: widget.overlay,
+          ),
+        )
       ],
     );
   }
 
-  Widget _getPlatformQrView(GlobalKey key) {
+  Widget _getPlatformQrView() {
     Widget _platformQrView;
     switch (defaultTargetPlatform) {
       case TargetPlatform.android:
         _platformQrView = AndroidView(
           viewType: 'net.touchcapture.qr.flutterqr/qrview',
           onPlatformViewCreated: _onPlatformViewCreated,
+          creationParams:
+              _QrCameraSettings(cameraFacing: widget.cameraFacing).toMap(),
+          creationParamsCodec: StandardMessageCodec(),
         );
         break;
       case TargetPlatform.iOS:
@@ -142,8 +111,7 @@ class _QRViewState extends State<QRView> {
           viewType: 'net.touchcapture.qr.flutterqr/qrview',
           onPlatformViewCreated: _onPlatformViewCreated,
           creationParams:
-              _CreationParams.fromWidget(MediaQuery.of(context).size.width, 400)
-                  .toMap(),
+              _QrCameraSettings(cameraFacing: widget.cameraFacing).toMap(),
           creationParamsCodec: StandardMessageCodec(),
         );
         break;
@@ -155,101 +123,178 @@ class _QRViewState extends State<QRView> {
   }
 
   void _onPlatformViewCreated(int id) {
-    if (widget.onQRViewCreated == null) {
-      return;
-    }
-
     // We pass the cutout size so that the scanner respects the scan area.
     var cutOutSize = 0.0;
     if (widget.overlay != null) {
       cutOutSize = (widget.overlay as QrScannerOverlayShape).cutOutSize;
     }
 
-    widget.onQRViewCreated(QRViewController._(id, widget.key, cutOutSize));
-  }
-}
+    _channel = MethodChannel('net.touchcapture.qr.flutterqr/qrview_$id');
 
-class _CreationParams {
-  _CreationParams({this.width, this.height});
+    // Start scan after creation of the view
+    final controller = QRViewController._(
+        _channel, widget.key, cutOutSize, widget.onPermissionSet)
+      .._startScan(widget.key, cutOutSize, widget.formatsAllowed);
 
-  static _CreationParams fromWidget(double width, double height) {
-    return _CreationParams(
-      width: width,
-      height: height,
-    );
+    // Initialize the controller for controlling the QRView
+    if (widget.onQRViewCreated != null) {
+      widget.onQRViewCreated(controller);
+    }
   }
+}
 
-  final double width;
-  final double height;
+class _QrCameraSettings {
+  _QrCameraSettings({
+    this.cameraFacing,
+  });
+
+  final CameraFacing cameraFacing;
 
   Map<String, dynamic> toMap() {
     return <String, dynamic>{
-      'width': width,
-      'height': height,
+      'cameraFacing': cameraFacing.index,
     };
   }
 }
 
 class QRViewController {
-  QRViewController._(int id, GlobalKey qrKey, double scanArea)
-      : _channel = MethodChannel('net.touchcapture.qr.flutterqr/qrview_$id') {
-    updateDimensions(qrKey, scanArea: scanArea);
-    _channel.setMethodCallHandler(
-      (call) async {
-        switch (call.method) {
-          case scanMethodCall:
-            if (call.arguments != null) {
-              final args = call.arguments as Map;
-              final code = args['code'] as String;
-              final rawType = args['type'] as String;
-              // Raw bytes are only supported by Android.
-              final rawBytes = args['rawBytes'] as List<int>;
-              final format = _formatNames[rawType];
-              if (format != null) {
-                final barcode = Barcode(code, format, rawBytes);
-                _scanUpdateController.sink.add(barcode);
-              } else {
-                throw Exception('Unexpected barcode type $rawType');
-              }
+  QRViewController._(MethodChannel channel, GlobalKey qrKey, double scanArea,
+      PermissionSetCallback onPermissionSet)
+      : _channel = channel {
+    _channel.setMethodCallHandler((call) async {
+      switch (call.method) {
+        case 'onRecognizeQR':
+          if (call.arguments != null) {
+            final args = call.arguments as Map;
+            final code = args['code'] as String;
+            final rawType = args['type'] as String;
+            // Raw bytes are only supported by Android.
+            final rawBytes = args['rawBytes'] as List<int>;
+            final format = BarcodeTypesExtension.fromString(rawType);
+            if (format != null) {
+              final barcode = Barcode(code, format, rawBytes);
+              _scanUpdateController.sink.add(barcode);
+            } else {
+              throw Exception('Unexpected barcode type $rawType');
             }
-        }
-      },
-    );
+          }
+          break;
+        case 'onPermissionSet':
+          await getSystemFeatures(); // if we have no permission all features will not be avaible
+          if (call.arguments != null) {
+            if (call.arguments as bool) {
+              _hasPermissions = true;
+            } else {
+              _hasPermissions = false;
+            }
+            if (onPermissionSet != null) {
+              onPermissionSet(this, call.arguments as bool);
+            }
+          }
+          break;
+      }
+    });
   }
 
-  static const scanMethodCall = 'onRecognizeQR';
-
   final MethodChannel _channel;
-
   final StreamController<Barcode> _scanUpdateController =
       StreamController<Barcode>();
 
   Stream<Barcode> get scannedDataStream => _scanUpdateController.stream;
 
-  void flipCamera() {
-    _channel.invokeMethod('flipCamera');
+  SystemFeatures _features;
+  bool _hasPermissions;
+
+  SystemFeatures get systemFeatures => _features;
+  bool get hasPermissions => _hasPermissions;
+
+  /// Starts the barcode scanner
+  Future<void> _startScan(GlobalKey key, double cutOutSize,
+      List<BarcodeFormat> barcodeFormats) async {
+    // We need to update the dimension before the scan is started.
+    QRViewController.updateDimensions(key, _channel, scanArea: cutOutSize);
+    return _channel.invokeMethod(
+        'startScan', barcodeFormats?.map((e) => e.asInt())?.toList() ?? []);
   }
 
-  void toggleFlash() {
-    _channel.invokeMethod('toggleFlash');
+  /// Gets information about which camera is active.
+  Future<CameraFacing> getCameraInfo() async {
+    try {
+      return CameraFacing
+          .values[await _channel.invokeMethod('getCameraInfo') as int];
+    } on PlatformException catch (e) {
+      throw CameraException(e.code, e.message);
+    }
+  }
+
+  /// Flips the camera between available modes
+  Future<CameraFacing> flipCamera() async {
+    try {
+      return CameraFacing
+          .values[await _channel.invokeMethod('flipCamera') as int];
+    } on PlatformException catch (e) {
+      throw CameraException(e.code, e.message);
+    }
   }
 
-  void pauseCamera() {
-    _channel.invokeMethod('pauseCamera');
+  /// Get flashlight status
+  Future<bool> getFlashStatus() async {
+    try {
+      return await _channel.invokeMethod('getFlashInfo');
+    } on PlatformException catch (e) {
+      throw CameraException(e.code, e.message);
+    }
+  }
+
+  /// Toggles the flashlight between available modes
+  Future<void> toggleFlash() async {
+    try {
+      await _channel.invokeMethod('toggleFlash') as bool;
+    } on PlatformException catch (e) {
+      throw CameraException(e.code, e.message);
+    }
   }
 
-  void resumeCamera() {
-    _channel.invokeMethod('resumeCamera');
+  /// Pauses barcode scanning
+  Future<void> pauseCamera() async {
+    try {
+      await _channel.invokeMethod('pauseCamera');
+    } on PlatformException catch (e) {
+      throw CameraException(e.code, e.message);
+    }
+  }
+
+  /// Resumes barcode scanning
+  Future<void> resumeCamera() async {
+    try {
+      await _channel.invokeMethod('resumeCamera');
+    } on PlatformException catch (e) {
+      throw CameraException(e.code, e.message);
+    }
+  }
+
+  /// Returns which features are available on device.
+  Future<SystemFeatures> getSystemFeatures() async {
+    try {
+      var features =
+          await _channel.invokeMapMethod<String, dynamic>('getSystemFeatures');
+      return SystemFeatures.fromJson(features);
+    } on PlatformException catch (e) {
+      throw CameraException(e.code, e.message);
+    }
   }
 
+  /// Disposes the barcode stream.
   void dispose() {
     _scanUpdateController.close();
   }
 
-  void updateDimensions(GlobalKey key, {double scanArea}) {
+  /// Updates the view dimensions for iOS.
+  static void updateDimensions(GlobalKey key, MethodChannel channel,
+      {double scanArea}) {
     if (defaultTargetPlatform == TargetPlatform.iOS) {
       final RenderBox renderBox = key.currentContext.findRenderObject();
-      _channel.invokeMethod('setDimensions', {
+      channel.invokeMethod('setDimensions', {
         'width': renderBox.size.width,
         'height': renderBox.size.height,
         'scanArea': scanArea ?? 0

lib/src/types/barcode.dart

@@ -0,0 +1,16 @@
+import 'barcode_format.dart';
+
+/// The [Barcode] object holds information about the barcode or qr code.
+///
+/// [code] is the content of the barcode.
+/// [format] displays which type the code is.
+/// Only for Android, [rawBytes] gives a list of bytes of the result.
+class Barcode {
+  Barcode(this.code, this.format, this.rawBytes);
+
+  final String code;
+  final BarcodeFormat format;
+
+  /// Raw bytes are only supported by Android.
+  final List<int> rawBytes;
+}

lib/src/types/barcode_format.dart

@@ -0,0 +1,174 @@
+enum BarcodeFormat {
+  /// Aztec 2D barcode format.
+  aztec,
+
+  /// CODABAR 1D format.
+  codabar,
+
+  /// Code 39 1D format.
+  code39,
+
+  /// Code 93 1D format.
+  code93,
+
+  /// Code 128 1D format.
+  code128,
+
+  /// Data Matrix 2D barcode format.
+  dataMatrix,
+
+  /// EAN-8 1D format.
+  ean8,
+
+  /// EAN-13 1D format.
+  ean13,
+
+  /// ITF (Interleaved Two of Five) 1D format.
+  itf,
+
+  /// MaxiCode 2D barcode format.
+  maxicode,
+
+  /// PDF417 format.
+  pdf417,
+
+  /// QR Code 2D barcode format.
+  qrcode,
+
+  /// RSS 14
+  rss14,
+
+  /// RSS EXPANDED
+  rssExpanded,
+
+  /// UPC-A 1D format.
+  upcA,
+
+  /// UPC-E 1D format.
+  upcE,
+
+  /// UPC/EAN extension format. Not a stand-alone format.
+  upcEanExtension
+}
+
+extension BarcodeTypesExtension on BarcodeFormat {
+  int asInt() {
+    return index;
+  }
+
+  static BarcodeFormat fromString(String format) {
+    switch (format) {
+      case 'AZTEC':
+        return BarcodeFormat.aztec;
+        break;
+      case 'CODABAR':
+        return BarcodeFormat.codabar;
+        break;
+      case 'CODE_39':
+        return BarcodeFormat.code39;
+        break;
+      case 'CODE_93':
+        return BarcodeFormat.code93;
+        break;
+      case 'CODE_128':
+        return BarcodeFormat.code128;
+        break;
+      case 'DATA_MATRIX':
+        return BarcodeFormat.dataMatrix;
+        break;
+      case 'EAN_8':
+        return BarcodeFormat.ean8;
+        break;
+      case 'EAN_13':
+        return BarcodeFormat.ean13;
+        break;
+      case 'ITF':
+        return BarcodeFormat.itf;
+        break;
+      case 'MAXICODE':
+        return BarcodeFormat.maxicode;
+        break;
+      case 'PDF_417':
+        return BarcodeFormat.pdf417;
+        break;
+      case 'QR_CODE':
+        return BarcodeFormat.qrcode;
+        break;
+      case 'RSS14':
+        return BarcodeFormat.rss14;
+        break;
+      case 'RSS_EXPANDED':
+        return BarcodeFormat.rssExpanded;
+        break;
+      case 'UPC_A':
+        return BarcodeFormat.upcA;
+        break;
+      case 'UPC_E':
+        return BarcodeFormat.upcE;
+        break;
+      case 'UPC_EAN_EXTENSION':
+        return BarcodeFormat.upcEanExtension;
+        break;
+      default:
+        return null;
+    }
+  }
+
+  String get formatName {
+    switch (this) {
+      case BarcodeFormat.aztec:
+        return 'AZTEC';
+        break;
+      case BarcodeFormat.codabar:
+        return 'CODABAR';
+        break;
+      case BarcodeFormat.code39:
+        return 'CODE_39';
+        break;
+      case BarcodeFormat.code93:
+        return 'CODE_93';
+        break;
+      case BarcodeFormat.code128:
+        return 'CODE_128';
+        break;
+      case BarcodeFormat.dataMatrix:
+        return 'DATA_MATRIX';
+        break;
+      case BarcodeFormat.ean8:
+        return 'EAN_8';
+        break;
+      case BarcodeFormat.ean13:
+        return 'EAN_13';
+        break;
+      case BarcodeFormat.itf:
+        return 'ITF';
+        break;
+      case BarcodeFormat.maxicode:
+        return 'MAXICODE';
+        break;
+      case BarcodeFormat.pdf417:
+        return 'PDF_417';
+        break;
+      case BarcodeFormat.qrcode:
+        return 'QR_CODE';
+        break;
+      case BarcodeFormat.rss14:
+        return 'RSS14';
+        break;
+      case BarcodeFormat.rssExpanded:
+        return 'RSS_EXPANDED';
+        break;
+      case BarcodeFormat.upcA:
+        return 'UPC_A';
+        break;
+      case BarcodeFormat.upcE:
+        return 'UPC_E';
+        break;
+      case BarcodeFormat.upcEanExtension:
+        return 'UPC_EAN_EXTENSION';
+        break;
+      default:
+        return 'NOT_VALID';
+    }
+  }
+}

lib/src/types/camera.dart

@@ -0,0 +1,7 @@
+enum CameraFacing {
+  /// Shows back facing camera.
+  back,
+
+  /// Shows front facing camera.
+  front
+}

lib/src/types/camera_exception.dart

@@ -0,0 +1,14 @@
+/// This is thrown when the plugin reports an error.
+class CameraException implements Exception {
+  /// Creates a new camera exception with the given error code and description.
+  CameraException(this.code, this.description);
+
+  /// Error code.
+  String code;
+
+  /// Textual description of the error.
+  String description;
+
+  @override
+  String toString() => 'CameraException($code, $description)';
+}

lib/src/types/features.dart

@@ -0,0 +1,13 @@
+class SystemFeatures {
+  SystemFeatures(this.hasFlash, this.hasBackCamera, this.hasFrontCamera);
+
+  factory SystemFeatures.fromJson(Map<String, dynamic> features) =>
+      SystemFeatures(
+          features['hasFlash'] ?? false,
+          features['hasBackCamera'] ?? false,
+          features['hasFrontCamera'] ?? false);
+
+  final bool hasFlash;
+  final bool hasFrontCamera;
+  final bool hasBackCamera;
+}

pubspec.yaml

@@ -5,7 +5,7 @@ homepage: https://juliuscanute.com
 repository: https://github.com/juliuscanute/qr_code_scanner
 
 environment:
-  sdk: ">=2.3.0 <3.0.0"
+  sdk: ">=2.6.0 <3.0.0"
   flutter: ^1.10.0
 
 dependencies: