Created CustomFramingRectBarcodeView to support changing cutOutBottomOffset

android/src/main/kotlin/net/touchcapture/qr/flutterqr/CustomFramingRectBarcodeView.java

@@ -0,0 +1,50 @@
+package net.touchcapture.qr.flutterqr;
+
+import android.content.Context;
+import android.graphics.Rect;
+import android.util.AttributeSet;
+
+import com.journeyapps.barcodescanner.BarcodeView;
+import com.journeyapps.barcodescanner.Size;
+
+public class CustomFramingRectBarcodeView extends BarcodeView {
+
+    private static final int BOTTOM_OFFSET_NOT_SET_VALUE = -1;
+
+    private int bottomOffset = BOTTOM_OFFSET_NOT_SET_VALUE;
+
+    public CustomFramingRectBarcodeView(Context context) {
+        super(context);
+    }
+
+    public CustomFramingRectBarcodeView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    public CustomFramingRectBarcodeView(Context context, AttributeSet attrs, int defStyleAttr) {
+        super(context, attrs, defStyleAttr);
+    }
+
+    @Override
+    protected Rect calculateFramingRect(Rect container, Rect surface) {
+        Rect containerArea = new Rect(container);
+        boolean intersects = containerArea.intersect(surface);//adjusts the containerArea (code from super.calculateFramingRect)
+        Rect scanAreaRect = super.calculateFramingRect(container, surface);
+        if (bottomOffset != BOTTOM_OFFSET_NOT_SET_VALUE) {//if the setFramingRect function was called, then we shift the scan area by Y
+            Rect scanAreaRectWithOffset = new Rect(scanAreaRect);
+            scanAreaRectWithOffset.bottom -= bottomOffset;
+            scanAreaRectWithOffset.top -= bottomOffset;
+
+            boolean belongsToContainer = scanAreaRectWithOffset.intersect(containerArea);
+            if(belongsToContainer){
+                return scanAreaRectWithOffset;
+            }
+        }
+        return scanAreaRect;
+    }
+
+    public void setFramingRect(int rectWidth, int rectHeight, int bottomOffset) {
+        this.bottomOffset = bottomOffset;
+        this.setFramingRectSize(new Size(rectWidth, rectHeight));
+    }
+}

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

@@ -13,8 +13,6 @@ import com.google.zxing.BarcodeFormat
 import com.google.zxing.ResultPoint
 import com.journeyapps.barcodescanner.BarcodeCallback
 import com.journeyapps.barcodescanner.BarcodeResult
-import com.journeyapps.barcodescanner.BarcodeView
-import com.journeyapps.barcodescanner.Size
 import io.flutter.plugin.common.BinaryMessenger
 import io.flutter.plugin.common.MethodCall
 import io.flutter.plugin.common.MethodChannel
@@ -27,7 +25,7 @@ class QRView(private val context: Context, messenger: BinaryMessenger, private v
 
     private var isTorchOn: Boolean = false
     private var isPaused: Boolean = false
-    private var barcodeView: BarcodeView? = null
+    private var barcodeView: CustomFramingRectBarcodeView? = null
     private val channel: MethodChannel = MethodChannel(messenger, "net.touchcapture.qr.flutterqr/qrview_$id")
     private var permissionGranted: Boolean = false
 
@@ -193,9 +191,10 @@ class QRView(private val context: Context, messenger: BinaryMessenger, private v
         return initBarCodeView().apply {}!!
     }
 
-    private fun initBarCodeView(): BarcodeView? {
+    private fun initBarCodeView(): CustomFramingRectBarcodeView? {
         if (barcodeView == null) {
-            barcodeView = BarcodeView(Shared.activity)
+            barcodeView =
+                CustomFramingRectBarcodeView(Shared.activity)
             if (params["cameraFacing"] as Int == 1) {
                 barcodeView?.cameraSettings?.requestedCameraId = CameraInfo.CAMERA_FACING_FRONT
             }
@@ -255,7 +254,7 @@ class QRView(private val context: Context, messenger: BinaryMessenger, private v
     }
 
     private fun setScanAreaSize(dpScanAreaWidth: Double, dpScanAreaHeight: Double) {
-        barcodeView?.framingRectSize = Size(convertDpToPixels(dpScanAreaWidth), convertDpToPixels(dpScanAreaHeight))
+        barcodeView?.setFramingRect (convertDpToPixels(dpScanAreaWidth), convertDpToPixels(dpScanAreaHeight), convertDpToPixels(150.0))
     }
 
     private fun convertDpToPixels(dp: Double) = (dp * context.resources.displayMetrics.density).toInt()

example/lib/main.dart

@@ -151,11 +151,13 @@ class _QRViewExampleState extends State<QRViewExample> {
       key: qrKey,
       onQRViewCreated: _onQRViewCreated,
       overlay: QrScannerOverlayShape(
-          borderColor: Colors.red,
-          borderRadius: 10,
-          borderLength: 30,
-          borderWidth: 10,
-          cutOutSize: scanArea),
+        borderColor: Colors.red,
+        borderRadius: 10,
+        borderLength: 30,
+        borderWidth: 10,
+        cutOutSize: /*scanArea*/100,
+        cutOutBottomOffset: 150,
+      ),
       onPermissionSet: (ctrl, p) => _onPermissionSet(context, ctrl, p),
     );
   }