Add ZoomFactor property and implement platform zoom on iOS/Android/Windows

BigIslandBarcode/MainPage.xaml

@@ -11,13 +11,15 @@
 			x:Name="barcodeView"
 			BarcodesDetected="BarcodesDetected"
 			 />
-
-		<Grid
+        <Grid Grid.Row="1" VerticalOptions="End" HorizontalOptions="Fill" BackgroundColor="#aa000000">
+            <Slider Minimum="0" Maximum="1" ValueChanged="ZoomFactorChanged" />
+        </Grid>
+        <Grid
 			Grid.Row="0"
 			BackgroundColor="#aa000000">
 			<Label x:Name="ResultLabel" Grid.Row="2" Text="Top text..." HorizontalOptions="Center" VerticalOptions="Center" TextColor="White" />
 		</Grid>
-
+        
 		<Grid
 			Grid.Row="3"
 			BackgroundColor="#aa000000"
@@ -27,8 +29,8 @@
 			<Button Text="🔄️" Grid.Column="0" BackgroundColor="#aa000000" CornerRadius="8" BorderColor="Black" Clicked="SwitchCameraButton_Clicked" />
 
 			<Button Text="📷" Grid.Column="1" BackgroundColor="#aa000000" CornerRadius="8" BorderColor="Black" Clicked="SelectCameraButton_Clicked" />
-
-			<zxing:BarcodeGeneratorView
+            
+            <zxing:BarcodeGeneratorView
 				x:Name="barcodeGenerator"
 				Grid.Column="2"
 				HorizontalOptions="Center"

BigIslandBarcode/MainPage.xaml.cs

@@ -80,5 +80,12 @@ void TorchButton_Clicked(object sender, EventArgs e)
 		{
 			barcodeView.IsTorchOn = !barcodeView.IsTorchOn;
 		}
-	}
+
+        private void ZoomFactorChanged(object sender, ValueChangedEventArgs e)
+        {
+            var slider = (Slider)sender;
+            barcodeView.ZoomFactor = (float)e.NewValue;
+
+        }
+    }
 }

README.md

@@ -108,6 +108,18 @@ Toggle Torch
 cameraBarcodeReaderView.IsTorchOn = !cameraBarcodeReaderView.IsTorchOn;
 ```
 
+Set zoom (normalized 0..1)
+```csharp
+// 0 = minimum, 1 = maximum (values outside the range are clamped)
+cameraBarcodeReaderView.ZoomFactor = 0.5f;
+```
+
+Notes on zoom behavior:
+- The zoom factor is normalized (0..1) across platforms.
+- iOS maps 0..1 to the device zoom range [1, max], where max is capped to the maximum optical zoom (currently min of `ActiveFormat.VideoMaxZoomFactor` and `5x`) to avoid degraded digital zoom.
+- Android uses linear zoom via CameraX.
+- Windows maps the normalized value to the device `ZoomControl` range when supported.
+
 Flip between Rear/Front cameras
 ```csharp
 cameraBarcodeReaderView.CameraLocation
@@ -175,4 +187,3 @@ The `CharacterSet` property defaults to "UTF-8" if not specified. Other common v
 
 
 
-

ZXing.Net.MAUI.Controls/Controls/CameraBarcodeReaderView.cs

@@ -62,6 +62,15 @@ public CameraInfo SelectedCamera
 			set => SetValue(SelectedCameraProperty, value);
 		}
 
+		public static readonly BindableProperty ZoomFactorProperty =
+			BindableProperty.Create(nameof(ZoomFactor), typeof(float), typeof(CameraBarcodeReaderView), defaultValue: 0f);
+
+		public float ZoomFactor
+		{
+			get => (float)GetValue(ZoomFactorProperty);
+			set => SetValue(ZoomFactorProperty, value);
+		}
+
 		public void AutoFocus()
 			=> StrongHandler?.Invoke(nameof(AutoFocus), null);
 

ZXing.Net.MAUI.Controls/Controls/CameraView.cs

@@ -40,6 +40,15 @@ public CameraInfo SelectedCamera
 			set => SetValue(SelectedCameraProperty, value);
 		}
 
+		public static readonly BindableProperty ZoomFactorProperty =
+			BindableProperty.Create(nameof(ZoomFactor), typeof(float), typeof(CameraView), defaultValue: 0f);
+
+		public float ZoomFactor
+		{
+			get => (float)GetValue(ZoomFactorProperty);
+			set => SetValue(ZoomFactorProperty, value);
+		}
+
 		public void AutoFocus()
 			=> StrongHandler?.Invoke(nameof(AutoFocus), null);
 

ZXing.Net.MAUI/Apple/CameraManager.ios.maccatalyst.cs

@@ -199,6 +199,7 @@ public void UpdateCamera()
 				captureSession.AddInput(captureInput);
 
 				captureSession.StartRunning();
+
 			}
 		}
 
@@ -269,6 +270,27 @@ public void UpdateTorch(bool on)
 			}
 		}
 
+		partial void ApplyZoomFactor()
+		{
+			if (captureDevice == null)
+				return;
+
+			var minZoomFactor = 1f;
+			// Cap zoom to the max optical range (higher values can engage digital zoom and degrade clarity).
+			var maxZoomFactor = Math.Min((float)captureDevice.ActiveFormat.VideoMaxZoomFactor, 5.0f);
+			if (maxZoomFactor < minZoomFactor)
+				maxZoomFactor = minZoomFactor;
+
+			var normalizedZoomFactor = ZoomFactor * (maxZoomFactor - minZoomFactor) + minZoomFactor;
+			if (normalizedZoomFactor < minZoomFactor)
+				normalizedZoomFactor = minZoomFactor;
+			else if (normalizedZoomFactor > maxZoomFactor)
+				normalizedZoomFactor = maxZoomFactor;
+
+			CaptureDevicePerformWithLockedConfiguration(() =>
+				captureDevice.VideoZoomFactor = normalizedZoomFactor);
+		}
+
 		public void Focus(Microsoft.Maui.Graphics.Point point)
 		{
 			if (captureDevice == null)

ZXing.Net.MAUI/CameraBarcodeReaderViewHandler.cs

@@ -19,6 +19,7 @@ public partial class CameraBarcodeReaderViewHandler : ViewHandler<ICameraBarcode
             [nameof(ICameraBarcodeReaderView.IsTorchOn)] = (handler, virtualView) => handler.cameraManager?.UpdateTorch(virtualView.IsTorchOn),
             [nameof(ICameraBarcodeReaderView.CameraLocation)] = (handler, virtualView) => handler.cameraManager?.UpdateCameraLocation(virtualView.CameraLocation),
             [nameof(ICameraBarcodeReaderView.SelectedCamera)] = (handler, virtualView) => handler.cameraManager?.UpdateSelectedCamera(virtualView.SelectedCamera),
+            [nameof(ICameraBarcodeReaderView.ZoomFactor)] = (handler, virtualView) => handler.cameraManager?.UpdateZoomFactor(virtualView.ZoomFactor),
             [nameof(IView.Visibility)] = MapVisibility
         };
 

ZXing.Net.MAUI/CameraManager.cs

@@ -22,6 +22,7 @@ public CameraManager(IMauiContext context, CameraLocation cameraLocation)
 
 		public CameraLocation CameraLocation { get; private set; }
 		public CameraInfo SelectedCamera { get; private set; }
+		public float ZoomFactor { get; private set; }
 
 		/// <summary>
 		/// Gets a value indicating whether barcode scanning is supported on this device.
@@ -48,7 +49,15 @@ public void UpdateSelectedCamera(CameraInfo cameraInfo)
 			UpdateCamera();
 		}
 
+		public void UpdateZoomFactor(float zoomFactor)
+		{
+			ZoomFactor = Math.Clamp(zoomFactor, 0f, 1f);
+			ApplyZoomFactor();
+		}
+
 		public static async Task<bool> CheckPermissions()
 			=> (await Permissions.RequestAsync<Permissions.Camera>()) == PermissionStatus.Granted;
+
+		partial void ApplyZoomFactor();
 	}
 }

ZXing.Net.MAUI/CameraViewHandler.cs

@@ -15,6 +15,7 @@ public partial class CameraViewHandler : ViewHandler<ICameraView, NativePlatform
 			[nameof(ICameraView.IsTorchOn)] = (handler, virtualView) => handler.cameraManager?.UpdateTorch(virtualView.IsTorchOn),
 			[nameof(ICameraView.CameraLocation)] = (handler, virtualView) => handler.cameraManager?.UpdateCameraLocation(virtualView.CameraLocation),
 			[nameof(ICameraView.SelectedCamera)] = (handler, virtualView) => handler.cameraManager?.UpdateSelectedCamera(virtualView.SelectedCamera),
+			[nameof(ICameraView.ZoomFactor)] = (handler, virtualView) => handler.cameraManager?.UpdateZoomFactor(virtualView.ZoomFactor),
 			[nameof(IView.Visibility)] = MapVisibility
 		};
 

ZXing.Net.MAUI/ICameraView.cs

@@ -14,6 +14,8 @@ public interface ICameraView : IView, ICameraFrameAnalyzer
 
 		CameraInfo SelectedCamera { get; set; }
 
+		float ZoomFactor { get; set; }
+
 		//CameraMode Mode { get; set; }
 
 		void AutoFocus();

ZXing.Net.MAUI/Net/CameraManager.net.cs

@@ -34,6 +34,10 @@ public void UpdateCamera()
         public void UpdateTorch(bool on)
             => LogUnsupported();
 
+        partial void ApplyZoomFactor()
+        {
+        }
+
         public void Focus(Microsoft.Maui.Graphics.Point point)
             => LogUnsupported();
 

ZXing.Net.MAUI/Platforms/Android/CameraManager.android.cs

@@ -170,6 +170,8 @@ public void UpdateCamera()
                     // if not, this should be sufficient as a fallback
                     _camera = _cameraProvider.BindToLifecycle(maLifecycleOwner, _cameraSelector, _cameraPreview, _imageAnalyzer);
                 }
+
+                ApplyZoomFactor();
             }
         }
 
@@ -223,6 +225,11 @@ public void UpdateTorch(bool on)
             _camera?.CameraControl?.EnableTorch(on);
         }
 
+        partial void ApplyZoomFactor()
+        {
+            _camera?.CameraControl?.SetLinearZoom(ZoomFactor);
+        }
+
         public void Focus(Point point)
         {
 

ZXing.Net.MAUI/Platforms/Windows/CameraManager.windows.cs

@@ -209,6 +209,11 @@ public NativePlatformCameraPreviewView CreateNativeView()
 
 		public void UpdateTorch(bool on) => TryEnqueueUI(async () => await UpdateTorchAsync(on));
 
+		partial void ApplyZoomFactor()
+		{
+			TryEnqueueUI(async () => await ApplyZoomFactorAsync());
+		}
+
 		public void Focus(Microsoft.Maui.Graphics.Point point) => TryEnqueueUI(async () => await FocusAsync(point));
 
 		public void AutoFocus() => TryEnqueueUI(async () => await AutoFocusAsync());
@@ -633,6 +638,42 @@ private async Task UpdateTorchAsync(bool on)
 			}
 		}
 
+		private async Task ApplyZoomFactorAsync()
+		{
+			await MediaCaptureLifeLock.WaitAsync();
+
+			try
+			{
+				var zoomControl = _mediaCapture?.VideoDeviceController?.ZoomControl;
+				if (zoomControl?.Supported ?? false)
+				{
+					var minZoom = (float)zoomControl.Min;
+					var maxZoom = (float)zoomControl.Max;
+					if (maxZoom < minZoom)
+						maxZoom = minZoom;
+
+					var normalizedZoom = ZoomFactor * (maxZoom - minZoom) + minZoom;
+					if (normalizedZoom < minZoom)
+						normalizedZoom = minZoom;
+					else if (normalizedZoom > maxZoom)
+						normalizedZoom = maxZoom;
+
+					if (Math.Abs(zoomControl.Value - normalizedZoom) > float.Epsilon)
+					{
+						zoomControl.Value = normalizedZoom;
+					}
+				}
+			}
+			catch (Exception ex)
+			{
+				Debug.WriteLine(ex);
+			}
+			finally
+			{
+				MediaCaptureLifeLock.Release();
+			}
+		}
+
 		private async Task FocusAsync(Microsoft.Maui.Graphics.Point point)
 		{
 			await MediaCaptureLifeLock.WaitAsync();