Implemented activityAware interface.

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

@@ -1,42 +1,128 @@
 package net.touchcapture.qr.flutterqr
 
+import android.Manifest
+import android.app.Activity
+import android.content.Context
+import android.content.pm.PackageManager
+import android.os.Build
 import androidx.annotation.NonNull
 import io.flutter.embedding.engine.plugins.FlutterPlugin
+import io.flutter.embedding.engine.plugins.activity.ActivityAware
+import io.flutter.embedding.engine.plugins.activity.ActivityPluginBinding
 import io.flutter.plugin.common.MethodCall
+import io.flutter.plugin.common.MethodChannel
 import io.flutter.plugin.common.MethodChannel.MethodCallHandler
 import io.flutter.plugin.common.MethodChannel.Result
-import io.flutter.plugin.common.PluginRegistry.Registrar
+import io.flutter.plugin.common.PluginRegistry
 
 
-class FlutterQrPlugin : FlutterPlugin, MethodCallHandler {
+class FlutterQrPlugin : FlutterPlugin, MethodCallHandler, ActivityAware {
 
-    /** Plugin registration embedding v1 */
-    companion object {
-        @JvmStatic
-        fun registerWith(registrar: Registrar) {
-            FlutterQrPlugin().onAttachedToEngine(registrar)
-        }
-    }
+    var cameraPermissionContinuation: Runnable? = null
+    var requestingPermission = false
+//    private var activity: Activity? = null
+
+//    /** Plugin registration embedding v1 */
+//    companion object {
+//        @JvmStatic
+//        fun registerWith(registrar: Registrar) {
+//            FlutterQrPlugin().onAttachedToEngine(registrar)
+//        }
+//    }
 
     /** Plugin registration embedding v2 */
     override fun onAttachedToEngine(@NonNull flutterPluginBinding: FlutterPlugin.FlutterPluginBinding) {
-        onAttachedToEngine(flutterPluginBinding)
+        onAttachedToEngines(flutterPluginBinding)
     }
 
     override fun onDetachedFromEngine(binding: FlutterPlugin.FlutterPluginBinding) {
     }
 
-    private fun onAttachedToEngine(registrar: Registrar) {
-        registrar
-                .platformViewRegistry()
+    // TODO: Fix v1 embedding for Flutter < 1.12 support
+    /** Plugin start for both embedding v1 & v2 */
+    private fun onAttachedToEngines(binding: FlutterPlugin.FlutterPluginBinding) {
+        binding.platformViewRegistry
                 .registerViewFactory(
-                        "net.touchcapture.qr.flutterqr/qrview", QRViewFactory(registrar))
+                        "net.touchcapture.qr.flutterqr/qrview", QRViewFactory(binding.binaryMessenger))
     }
 
+//    private fun onAttachedToEngine(registrar: Registrar) {
+//        activity = registrar.activity()
+//        registrar.addRequestPermissionsResultListener(CameraRequestPermissionsListener())
+//        checkAndRequestPermission(null)
+//        registrar
+//                .platformViewRegistry()
+//                .registerViewFactory(
+//                        "net.touchcapture.qr.flutterqr/qrview", QRViewFactory(registrar))
+//    }
+
     override fun onMethodCall(call: MethodCall, result: Result) {
         when (call.method) {
-            "getPlatformVersion" -> result.success("Android ${android.os.Build.VERSION.RELEASE}")
-            else -> result.notImplemented()
+            "checkAndRequestPermission" -> checkAndRequestPermission(result)
+        }
+    }
+
+    override fun onAttachedToActivity(activityPluginBinding: ActivityPluginBinding) {
+        Shared.activityPluginBinding = activityPluginBinding
+        Shared.activity = activityPluginBinding.activity
+        activityPluginBinding.addRequestPermissionsResultListener(CameraRequestPermissionsListener())
+        checkAndRequestPermission(null)
+    }
+
+    override fun onDetachedFromActivityForConfigChanges() {
+        Shared.activityPluginBinding = null
+        Shared.activity = null
+    }
+
+    override fun onReattachedToActivityForConfigChanges(activityPluginBinding: ActivityPluginBinding) {
+        Shared.activityPluginBinding = activityPluginBinding
+        Shared.activity = activityPluginBinding.activity
+    }
+
+    override fun onDetachedFromActivity() {
+        Shared.activityPluginBinding = null
+        Shared.activity = null
+    }
+
+    private inner class CameraRequestPermissionsListener : PluginRegistry.RequestPermissionsResultListener {
+        override fun onRequestPermissionsResult(id: Int, permissions: Array<String>, grantResults: IntArray): Boolean {
+            if (id == QRView.CAMERA_REQUEST_ID && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
+                cameraPermissionContinuation?.run()
+                return true
+            }
+            return false
+        }
+    }
+
+    private fun hasCameraPermission(): Boolean {
+        return Build.VERSION.SDK_INT < Build.VERSION_CODES.M ||
+                Shared.activity?.checkSelfPermission(Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED
+    }
+
+    private fun checkAndRequestPermission(result: Result?) {
+        if (cameraPermissionContinuation != null) {
+            result?.error("cameraPermission", "Camera permission request ongoing", null);
+        }
+
+        cameraPermissionContinuation = Runnable {
+            cameraPermissionContinuation = null
+            if (!hasCameraPermission()) {
+                result?.error(
+                        "cameraPermission", "MediaRecorderCamera permission not granted", null)
+                return@Runnable
+            }
+        }
+
+        requestingPermission = false
+        if (hasCameraPermission()) {
+            cameraPermissionContinuation?.run()
+        } else {
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
+                requestingPermission = true
+                Shared.activity?.requestPermissions(
+                        arrayOf(Manifest.permission.CAMERA),
+                        QRView.CAMERA_REQUEST_ID)
+            }
         }
     }
 }

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

@@ -1,12 +1,9 @@
 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.content.pm.PackageManager.PERMISSION_GRANTED
-import android.os.Build
 import android.os.Bundle
 import android.view.View
 import com.google.zxing.ResultPoint
@@ -14,39 +11,34 @@ import android.hardware.Camera.CameraInfo
 import com.journeyapps.barcodescanner.BarcodeCallback
 import com.journeyapps.barcodescanner.BarcodeResult
 import com.journeyapps.barcodescanner.BarcodeView
+import io.flutter.plugin.common.BinaryMessenger
 import io.flutter.plugin.common.MethodCall
 import io.flutter.plugin.common.MethodChannel
-import io.flutter.plugin.common.PluginRegistry
 import io.flutter.plugin.platform.PlatformView
-
-class QRView(private val registrar: PluginRegistry.Registrar, id: Int) :
-        PlatformView,MethodChannel.MethodCallHandler {
+class QRView(messenger: BinaryMessenger, id: Int, private val context: Context) :
+        PlatformView, MethodChannel.MethodCallHandler {
 
     companion object {
         const val CAMERA_REQUEST_ID = 513469796
     }
 
     var barcodeView: BarcodeView? = null
-    private val activity = registrar.activity()
-    var cameraPermissionContinuation: Runnable? = null
-    var requestingPermission = false
+
     private var isTorchOn: Boolean = false
     val channel: MethodChannel
 
     init {
-        registrar.addRequestPermissionsResultListener(CameraRequestPermissionsListener())
-        channel = MethodChannel(registrar.messenger(), "net.touchcapture.qr.flutterqr/qrview_$id")
+        channel = MethodChannel(messenger, "net.touchcapture.qr.flutterqr/qrview_$id")
         channel.setMethodCallHandler(this)
-        checkAndRequestPermission(null)
-        registrar.activity().application.registerActivityLifecycleCallbacks(object : Application.ActivityLifecycleCallbacks {
+        Shared.activity?.application?.registerActivityLifecycleCallbacks(object : Application.ActivityLifecycleCallbacks {
             override fun onActivityPaused(p0: Activity) {
-                if (p0 == registrar.activity()) {
+                if (p0 == Shared.activity) {
                     barcodeView?.pause()
                 }
             }
 
             override fun onActivityResumed(p0: Activity) {
-                if (p0 == registrar.activity()) {
+                if (p0 == Shared.activity) {
                     barcodeView?.resume()
                 }
             }
@@ -102,7 +94,7 @@ class QRView(private val registrar: PluginRegistry.Registrar, id: Int) :
     }
 
     private fun hasFlash(): Boolean {
-        return registrar.activeContext().packageManager
+        return context.packageManager
                 .hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH)
     }
 
@@ -120,7 +112,7 @@ class QRView(private val registrar: PluginRegistry.Registrar, id: Int) :
     }
 
     private fun createBarCodeView(): BarcodeView? {
-        val barcode = BarcodeView(registrar.activity())
+        val barcode = BarcodeView(Shared.activity)
         barcode.decodeContinuous(
                 object : BarcodeCallback {
                     override fun barcodeResult(result: BarcodeResult) {
@@ -138,27 +130,8 @@ class QRView(private val registrar: PluginRegistry.Registrar, id: Int) :
         barcodeView = null
     }
 
-    private inner class CameraRequestPermissionsListener : PluginRegistry.RequestPermissionsResultListener {
-        override fun onRequestPermissionsResult(id: Int, permissions: Array<String>, grantResults: IntArray): Boolean {
-            if (id == CAMERA_REQUEST_ID && grantResults[0] == PERMISSION_GRANTED) {
-                cameraPermissionContinuation?.run()
-                return true
-            }
-            return false
-        }
-    }
-
-    private fun hasCameraPermission(): Boolean {
-        return Build.VERSION.SDK_INT < Build.VERSION_CODES.M ||
-                activity.checkSelfPermission(Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED
-    }
-
-
     override fun onMethodCall(call: MethodCall, result: MethodChannel.Result) {
-        when(call?.method){
-            "checkAndRequestPermission" -> {
-                checkAndRequestPermission(result)
-            }
+        when(call.method){
             "flipCamera" -> {
                 flipCamera()
             }
@@ -174,33 +147,6 @@ class QRView(private val registrar: PluginRegistry.Registrar, id: Int) :
         }
     }
 
-    private fun checkAndRequestPermission(result: MethodChannel.Result?) {
-        if (cameraPermissionContinuation != null) {
-            result?.error("cameraPermission", "Camera permission request ongoing", null);
-        }
-
-        cameraPermissionContinuation = Runnable {
-            cameraPermissionContinuation = null
-            if (!hasCameraPermission()) {
-                result?.error(
-                        "cameraPermission", "MediaRecorderCamera permission not granted", null)
-                return@Runnable
-            }
-        }
 
-        requestingPermission = false
-        if (hasCameraPermission()) {
-            cameraPermissionContinuation?.run()
-        } else {
-            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
-                requestingPermission = true
-                registrar
-                        .activity()
-                        .requestPermissions(
-                                arrayOf(Manifest.permission.CAMERA),
-                                CAMERA_REQUEST_ID)
-            }
-        }
-    }
 
 }

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

@@ -1,17 +1,17 @@
 package net.touchcapture.qr.flutterqr
 
 import android.content.Context
-import io.flutter.plugin.common.PluginRegistry
+import io.flutter.plugin.common.BinaryMessenger
 import io.flutter.plugin.common.StandardMessageCodec
 import io.flutter.plugin.platform.PlatformView
 import io.flutter.plugin.platform.PlatformViewFactory
 
 
-class QRViewFactory(private val registrar: PluginRegistry.Registrar) :
+class QRViewFactory(private val messenger: BinaryMessenger) :
         PlatformViewFactory(StandardMessageCodec.INSTANCE) {
 
     override fun create(context: Context, id: Int, obj: Any?): PlatformView {
-        return QRView(registrar,id)
+        return QRView(messenger, id, context)
     }
 
 }

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

@@ -0,0 +1,10 @@
+package net.touchcapture.qr.flutterqr
+
+import android.app.Activity
+import io.flutter.embedding.engine.plugins.activity.ActivityPluginBinding
+
+
+object Shared {
+    var activityPluginBinding: ActivityPluginBinding? = null
+    var activity: Activity? = null
+}