Merge pull request juliansteenbakker#1456 from juliansteenbakker/feat/focus-zoom-lens

feat: tap to focus, initial zoom and more lenses

Author: juliansteenbakker

CHANGELOG.md

@@ -1,7 +1,18 @@
 ## NEXT
 
+**BREAKING CHANGES**
+
+* [iOS] Increased minimum iOS level to 13 due to Flutter requirements.
+
+**Highlights**
+
+* [Apple & Android] Added tap to focus functionality. You can enable it in the `MobileScanner` widget.
+* [Apple & Android] You can now set the initial zoom factor using the `initialZoom` parameter in the `startOptions`.
+
+**Bug Fixes and Improvements**
+
 * [Android] Update to Java 17, and update other dependencies.
-* [iOS] Upgraded minimum iOS level to 13 due to Flutter requirements.
+* [Apple] Improved fallback for when camera is not found.
 
 ## 7.0.1
 
@@ -11,7 +22,7 @@
 
 This version finalizes all changes from the beta and release candidate cycles and introduces major improvements, bug fixes, and breaking changes.
 
-**BREAKING CHANGES:**
+**BREAKING CHANGES**
 
 * Requires Flutter 3.29.0 or higher.
 * The initial camera facing direction in `MobileScannerState` is now `CameraFacing.unknown`.

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

@@ -23,9 +23,13 @@ import androidx.camera.core.CameraSelector
 import androidx.camera.core.CameraXConfig
 import androidx.camera.core.ExperimentalGetImage
 import androidx.camera.core.ExperimentalLensFacing
+import androidx.camera.core.FocusMeteringAction
 import androidx.camera.core.ImageAnalysis
 import androidx.camera.core.ImageProxy
+import androidx.camera.core.MeteringPoint
+import androidx.camera.core.MeteringPointFactory
 import androidx.camera.core.Preview
+import androidx.camera.core.SurfaceOrientedMeteringPointFactory
 import androidx.camera.core.SurfaceRequest
 import androidx.camera.core.TorchState
 import androidx.camera.core.resolutionselector.ResolutionSelector
@@ -343,6 +347,7 @@ class MobileScanner(
         detectionTimeout: Long,
         cameraResolutionWanted: Size?,
         invertImage: Boolean,
+        initialZoom: Double,
     ) {
         this.detectionSpeed = detectionSpeed
         this.detectionTimeout = detectionTimeout
@@ -471,6 +476,18 @@ class MobileScanner(
                 if (it.cameraInfo.hasFlashUnit()) {
                     it.cameraControl.enableTorch(torch)
                 }
+
+                try {
+                    if (initialZoom in 0.0..1.0) {
+                        it.cameraControl.setLinearZoom(initialZoom.toFloat())
+                    } else {
+                        it.cameraControl.setZoomRatio(initialZoom.toFloat())
+                    }
+                } catch (e: Exception) {
+                    mobileScannerErrorCallback(ZoomNotInRange())
+
+                    return@addListener
+                }
             }
 
             val resolution = analysis.resolutionInfo!!.resolution
@@ -701,6 +718,23 @@ class MobileScanner(
         camera?.cameraControl?.setZoomRatio(1f)
     }
 
+    fun setFocus(x: Float, y: Float) {
+        val cam = camera ?: throw ZoomWhenStopped()
+
+        // Ensure x,y are normalized (0f..1f)
+        if (x !in 0f..1f || y !in 0f..1f) {
+            throw IllegalArgumentException("Focus coordinates must be between 0.0 and 1.0")
+        }
+
+        val factory: MeteringPointFactory = SurfaceOrientedMeteringPointFactory(1f, 1f)
+        val afPoint: MeteringPoint = factory.createPoint(x, y)
+
+        val action = FocusMeteringAction.Builder(afPoint, FocusMeteringAction.FLAG_AF)
+            .build()
+
+        cam.cameraControl.startFocusAndMetering(action)
+    }
+
     /**
      * Dispose of this scanner instance.
      */

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

@@ -151,6 +151,7 @@ class MobileScannerHandler(
             "setScale" -> setScale(call, result)
             "resetScale" -> resetScale(result)
             "updateScanWindow" -> updateScanWindow(call, result)
+            "setFocus" -> setFocus(call, result)
             else -> result.notImplemented()
         }
     }
@@ -172,6 +173,7 @@ class MobileScannerHandler(
             null
         }
         val invertImage: Boolean = call.argument<Boolean>("invertImage") ?: false
+        val initialZoom: Double = call.argument<Double>("initialZoom") ?: 1.0
 
         val barcodeScannerOptions: BarcodeScannerOptions? = buildBarcodeScannerOptions(formats, autoZoom)
 
@@ -243,6 +245,7 @@ class MobileScannerHandler(
             timeout.toLong(),
             cameraResolution,
             invertImage,
+            initialZoom
         )
     }
 
@@ -327,7 +330,7 @@ class MobileScannerHandler(
     private fun buildBarcodeScannerOptions(formats: List<Int>?, autoZoom: Boolean): BarcodeScannerOptions? {
         val builder : BarcodeScannerOptions.Builder?
         if (formats == null) {
-           builder = BarcodeScannerOptions.Builder()
+            builder = BarcodeScannerOptions.Builder()
         } else {
             val formatsList: MutableList<Int> = mutableListOf()
 
@@ -374,4 +377,36 @@ class MobileScannerHandler(
         }
         return maxZoom
     }
+
+    private fun setFocus(call: MethodCall, result: MethodChannel.Result) {
+        val dx = call.argument<Double>("dx")?.toFloat()
+        val dy = call.argument<Double>("dy")?.toFloat()
+
+        if (dx == null || dy == null || dx !in 0f..1f || dy !in 0f..1f) {
+            result.error(
+                MobileScannerErrorCodes.INVALID_FOCUS_POINT,
+                MobileScannerErrorCodes.INVALID_FOCUS_POINT_MESSAGE,
+                null
+            )
+            return
+        }
+
+        try {
+            mobileScanner?.setFocus(dx, dy)
+            result.success(null)
+        } catch (e: ZoomWhenStopped) {
+            result.error(
+                MobileScannerErrorCodes.GENERIC_ERROR,
+                "Cannot set focus when camera is stopped.",
+                null
+            )
+        } catch (e: Exception) {
+            result.error(
+                MobileScannerErrorCodes.GENERIC_ERROR,
+                MobileScannerErrorCodes.GENERIC_ERROR_MESSAGE,
+                e.localizedMessage
+            )
+        }
+    }
+
 }

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

@@ -23,5 +23,7 @@ class MobileScannerErrorCodes {
         const val SET_SCALE_WHEN_STOPPED_ERROR = "MOBILE_SCANNER_SET_SCALE_WHEN_STOPPED_ERROR"
         const val SET_SCALE_WHEN_STOPPED_ERROR_MESSAGE = "The zoom scale cannot be changed when the camera is stopped."
         const val UNSUPPORTED_OPERATION_ERROR = "MOBILE_SCANNER_UNSUPPORTED_OPERATION" // Reserved for future use.
+        const val INVALID_FOCUS_POINT = "MOBILE_SCANNER_INVALID_FOCUS_POINT"
+        const val INVALID_FOCUS_POINT_MESSAGE = "The focus coordinates are not valid."
     }
 }

darwin/mobile_scanner/Sources/mobile_scanner/MobileScannerErrorCodes.swift

@@ -24,6 +24,8 @@ struct MobileScannerErrorCodes {
     static let GENERIC_ERROR_MESSAGE = "An unknown error occurred."
     // This message is used with the 'GENERIC_ERROR' error code.
     static let INVALID_ZOOM_SCALE_ERROR_MESSAGE = "The zoom scale should be between 0 and 1 (both inclusive)"
+    static let INVALID_FOCUS_POINT = "MOBILE_SCANNER_INVALID_FOCUS_POINT"
+    static let INVALID_FOCUS_POINT_MESSAGE = "The focus coordinates are not valid."
     static let NO_CAMERA_ERROR = "MOBILE_SCANNER_NO_CAMERA_ERROR"
     static let NO_CAMERA_ERROR_MESSAGE = "No cameras available."
     static let SET_SCALE_WHEN_STOPPED_ERROR = "MOBILE_SCANNER_SET_SCALE_WHEN_STOPPED_ERROR"

darwin/mobile_scanner/Sources/mobile_scanner/MobileScannerPlugin.swift

@@ -101,6 +101,8 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
             toggleTorch(result)
         case "setScale":
             setScale(call, result)
+        case "setFocus":
+            setFocus(call, result)
         case "resetScale":
             resetScale(call, result)
         case "pause":
@@ -346,6 +348,7 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
         let facing:Int = argReader.int(key: "facing") ?? 1
         let speed:Int = argReader.int(key: "speed") ?? 0
         let timeoutMs:Int = argReader.int(key: "timeout") ?? 0
+        let initialZoom: CGFloat = CGFloat(argReader.float(key: "initialZoom") ?? 1)
         symbologies = argReader.toSymbology()
         MobileScannerPlugin.returnImage = argReader.bool(key: "returnImage") ?? false
 
@@ -360,12 +363,24 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
 #endif
 
         // Open the camera device
+#if os(iOS)
+        if #available(iOS 13.0, *) {
+            device = AVCaptureDevice.DiscoverySession(deviceTypes: [.builtInTripleCamera, .builtInDualCamera, .builtInWideAngleCamera], mediaType: .video, position: position).devices.first
+        }
+#else
         if #available(macOS 10.15, *) {
             device = AVCaptureDevice.DiscoverySession(deviceTypes: [.builtInWideAngleCamera], mediaType: .video, position: position).devices.first
-        } else {
+        }
+#endif
+        
+        if (device == nil) {
             device = AVCaptureDevice.devices(for: .video).filter({$0.position == position}).first
         }
 
+        if (device == nil) {
+            device = AVCaptureDevice.default(for: .video)
+        }
+        
         if (device == nil) {
             result(FlutterError(code: MobileScannerErrorCodes.NO_CAMERA_ERROR,
                                 message: MobileScannerErrorCodes.NO_CAMERA_ERROR_MESSAGE,
@@ -380,7 +395,7 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
         captureSession!.beginConfiguration()
 
         // Check the zoom factor at switching from ultra wide camera to wide camera.
-        standardZoomFactor = 1
+        standardZoomFactor = initialZoom
 #if os(iOS)
         if #available(iOS 13.0, *) {
             for (index, actualDevice) in device.constituentDevices.enumerated() {
@@ -455,6 +470,13 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
                 if (torch) {
                     self.turnTorchOn()
                 }
+                
+                // Set the initial zoom factor
+                do {
+                    try self.setScaleInternal(initialZoom)
+                } catch {
+                    // Do nothing.
+                }
 
 #if os(iOS)
                 // The height and width are swapped because the default video orientation for ios is landscape right, but mobile_scanner operates in portrait mode.
@@ -586,6 +608,43 @@ public class MobileScannerPlugin: NSObject, FlutterPlugin, FlutterStreamHandler,
 
     }
 
+    private func setFocus(_ call: FlutterMethodCall, _ result: @escaping FlutterResult) {
+        guard let args = call.arguments as? [String: Any],
+                  let dx = args["dx"] as? CGFloat,
+                  let dy = args["dy"] as? CGFloat else {
+                result(FlutterError(code: MobileScannerErrorCodes.INVALID_FOCUS_POINT,
+                                    message: MobileScannerErrorCodes.INVALID_FOCUS_POINT_MESSAGE,
+                                    details: nil))
+                return
+            }
+            let focusPoint = CGPoint(x: dx, y: dy)
+        
+        do {
+            if (device == nil) {
+                throw MobileScannerError.zoomWhenStopped
+            }
+
+    #if os(iOS)
+                if device.isFocusPointOfInterestSupported {
+                    do {
+                        try device.lockForConfiguration()
+                        device.focusPointOfInterest = focusPoint
+                        device.focusMode = .autoFocus
+                        device.unlockForConfiguration()
+                    } catch {
+                        throw MobileScannerError.zoomError(error)
+                    }
+                }
+    #endif
+        
+            result(nil)
+        } catch {
+            result(FlutterError(code: MobileScannerErrorCodes.GENERIC_ERROR,
+                                message: MobileScannerErrorCodes.GENERIC_ERROR_MESSAGE,
+                                details: nil))
+        }
+    }
+
 #if os(iOS)
     /// Set the device orientation if it differs from previous orientation
     func setDeviceOrientation(orientation: UIDeviceOrientation) {
@@ -891,6 +950,10 @@ class MapArgumentReader {
     func int(key: String) -> Int? {
         return (args?[key] as? NSNumber)?.intValue
     }
+    
+    func float(key: String) -> Float? {
+        return (args?[key] as? NSNumber)?.floatValue
+    }
 
     func bool(key: String) -> Bool? {
         return (args?[key] as? NSNumber)?.boolValue

example/ios/Runner.xcodeproj/project.pbxproj

@@ -3,7 +3,7 @@
 	archiveVersion = 1;
 	classes = {
 	};
-	objectVersion = 60;
+	objectVersion = 54;
 	objects = {
 
 /* Begin PBXBuildFile section */