Improve CameraView Performance

samples/CommunityToolkit.Maui.Sample/Pages/Views/CameraView/CameraViewPage.xaml

@@ -5,12 +5,11 @@
                 xmlns:toolkit="http://schemas.microsoft.com/dotnet/2022/maui/toolkit"
                 xmlns:viewModels="clr-namespace:CommunityToolkit.Maui.Sample.ViewModels.Views"
                 Title="CameraView"
-                Unloaded="OnUnloaded"
                 x:Class="CommunityToolkit.Maui.Sample.Pages.Views.CameraViewPage"
                 x:TypeArguments="viewModels:CameraViewViewModel"
                 x:DataType="viewModels:CameraViewViewModel">
 
-    <Grid RowDefinitions="200,*,Auto,Auto" ColumnDefinitions="3*,*">
+    <Grid RowDefinitions="Auto,*,Auto,Auto" ColumnDefinitions="3*,*">
         <toolkit:CameraView
             x:Name="Camera"
             Grid.Column="0" Grid.Row="0" Grid.ColumnSpan="2" Grid.RowSpan="3"

samples/CommunityToolkit.Maui.Sample/Pages/Views/CameraView/CameraViewPage.xaml.cs

@@ -1,4 +1,3 @@
-using System.Diagnostics;
 using CommunityToolkit.Maui.Core;
 using CommunityToolkit.Maui.Sample.ViewModels.Views;
 using CommunityToolkit.Maui.Storage;
@@ -10,7 +9,6 @@ public sealed partial class CameraViewPage : BasePage<CameraViewViewModel>
 	readonly IFileSaver fileSaver;
 	readonly string imagePath;
 
-	int pageCount;
 	Stream videoRecordingStream = Stream.Null;
 
 	public CameraViewPage(CameraViewViewModel viewModel, IFileSystem fileSystem, IFileSaver fileSaver) : base(viewModel)
@@ -21,17 +19,15 @@ public CameraViewPage(CameraViewViewModel viewModel, IFileSystem fileSystem, IFi
 		imagePath = Path.Combine(fileSystem.CacheDirectory, "camera-view-image.jpg");
 
 		Camera.MediaCaptured += OnMediaCaptured;
-
-		Loaded += (s, e) => { pageCount = Navigation.NavigationStack.Count; };
 	}
 
 	protected override async void OnAppearing()
 	{
 		base.OnAppearing();
-		
+
 		var cameraPermissionsRequest = await Permissions.RequestAsync<Permissions.Camera>();
 		var microphonePermissionsRequest = await Permissions.RequestAsync<Permissions.Microphone>();
-		
+
 		if (cameraPermissionsRequest is not PermissionStatus.Granted)
 		{
 			await Shell.Current.CurrentPage.DisplayAlertAsync("Camera permission is not granted.", "Please grant the permission to use this feature.", "OK");
@@ -43,20 +39,14 @@ protected override async void OnAppearing()
 			await Shell.Current.CurrentPage.DisplayAlertAsync("Microphone permission is not granted.", "Please grant the permission to use this feature.", "OK");
 			return;
 		}
-
-		var cancellationTokenSource = new CancellationTokenSource(TimeSpan.FromSeconds(3));
-		await BindingContext.RefreshCamerasCommand.ExecuteAsync(cancellationTokenSource.Token);
 	}
 
-	// https://github.com/dotnet/maui/issues/16697
 	// https://github.com/dotnet/maui/issues/15833
 	protected override void OnNavigatedFrom(NavigatedFromEventArgs args)
 	{
 		base.OnNavigatedFrom(args);
 
-		Debug.WriteLine($"< < OnNavigatedFrom {pageCount} {Navigation.NavigationStack.Count}");
-
-		if (Navigation.NavigationStack.Count < pageCount)
+		if (!Shell.Current.Navigation.NavigationStack.Contains(this))
 		{
 			Cleanup();
 		}
@@ -75,12 +65,6 @@ async void OnImageTapped(object? sender, TappedEventArgs args)
 	void Cleanup()
 	{
 		Camera.MediaCaptured -= OnMediaCaptured;
-		Camera.Handler?.DisconnectHandler();
-	}
-
-	void OnUnloaded(object? sender, EventArgs? e)
-	{
-		//Cleanup();
 	}
 
 	void OnMediaCaptured(object? sender, MediaCapturedEventArgs e)
@@ -93,7 +77,7 @@ void OnMediaCaptured(object? sender, MediaCapturedEventArgs e)
 		{
 			// workaround for https://github.com/dotnet/maui/issues/13858
 #if ANDROID
-            image.Source = ImageSource.FromStream(() => File.OpenRead(imagePath));
+			image.Source = ImageSource.FromStream(() => File.OpenRead(imagePath));
 #else
 			image.Source = ImageSource.FromFile(imagePath);
 #endif
@@ -142,7 +126,7 @@ async void SaveVideo(object? sender, EventArgs? e)
 			var status = await Permissions.RequestAsync<Permissions.StorageWrite>();
 			if (status is not PermissionStatus.Granted)
 			{
-				await Shell.Current.CurrentPage.DisplayAlert("Storage permission is not granted.", "Please grant the permission to use this feature.", "OK");
+				await Shell.Current.CurrentPage.DisplayAlertAsync("Storage permission is not granted.", "Please grant the permission to use this feature.", "OK");
 				return;
 			}
 

samples/CommunityToolkit.Maui.Sample/ViewModels/Views/CameraView/CameraViewViewModel.cs

@@ -48,9 +48,6 @@ public CameraViewViewModel(ICameraProvider cameraProvider)
 	[ObservableProperty]
 	public partial string ResolutionText { get; set; } = string.Empty;
 
-	[RelayCommand]
-	async Task RefreshCameras(CancellationToken token) => await cameraProvider.RefreshAvailableCameras(token);
-
 	partial void OnFlashModeChanged(CameraFlashMode value)
 	{
 		UpdateFlashModeText();

src/CommunityToolkit.Maui.Camera/AppBuilderExtensions.shared.cs

@@ -12,7 +12,7 @@ namespace CommunityToolkit.Maui;
 [SupportedOSPlatform("android21.0")]
 [SupportedOSPlatform("ios15.0")]
 [SupportedOSPlatform("maccatalyst15.0")]
-[SupportedOSPlatform("tizen6.5")]
+[UnsupportedOSPlatform("tizen")]
 public static class AppBuilderExtensions
 {
 	/// <summary>
@@ -23,7 +23,7 @@ public static class AppBuilderExtensions
 	public static MauiAppBuilder UseMauiCommunityToolkitCamera(this MauiAppBuilder builder)
 	{
 		builder.Services.AddSingleton<ICameraProvider, CameraProvider>();
-		builder.ConfigureMauiHandlers(h => h.AddHandler<CameraView, CameraViewHandler>());
+		builder.ConfigureMauiHandlers(static h => h.AddHandler<CameraView, CameraViewHandler>());
 
 		return builder;
 	}

src/CommunityToolkit.Maui.Camera/CameraManager.android.cs

@@ -1,6 +1,5 @@
 using System.Runtime.Versioning;
 using Android.Content;
-using Android.Provider;
 using Android.Runtime;
 using Android.Views;
 using AndroidX.Camera.Core;
@@ -63,8 +62,48 @@ public async Task SetExtensionMode(int mode, CancellationToken token)
 
 	public void Dispose()
 	{
-		Dispose(true);
-		GC.SuppressFinalize(this);
+		CleanupVideoRecordingResources();
+
+		camera?.Dispose();
+		camera = null;
+
+		cameraControl?.Dispose();
+		cameraControl = null;
+
+		cameraPreview?.Dispose();
+		cameraPreview = null;
+
+		cameraExecutor?.Dispose();
+		cameraExecutor = null;
+
+		imageCapture?.Dispose();
+		imageCapture = null;
+
+		videoCapture?.Dispose();
+		videoCapture = null;
+
+		imageCallback?.Dispose();
+		imageCallback = null;
+
+		previewView?.Dispose();
+		previewView = null;
+
+		processCameraProvider?.UnbindAll();
+		processCameraProvider?.Dispose();
+		processCameraProvider = null;
+
+		resolutionSelector?.Dispose();
+		resolutionSelector = null;
+
+		resolutionFilter?.Dispose();
+		resolutionFilter = null;
+
+		orientationListener?.Disable();
+		orientationListener?.Dispose();
+		orientationListener = null;
+
+		videoRecordingStream?.Dispose();
+		videoRecordingStream = null;
 	}
 
 	// IN the future change the return type to be an alias
@@ -138,55 +177,7 @@ public async partial ValueTask UpdateCaptureResolution(Size resolution, Cancella
 		}
 	}
 
-	protected virtual void Dispose(bool disposing)
-	{
-		if (disposing)
-		{
-			CleanupVideoRecordingResources();
-
-			camera?.Dispose();
-			camera = null;
-
-			cameraControl?.Dispose();
-			cameraControl = null;
-
-			cameraPreview?.Dispose();
-			cameraPreview = null;
-
-			cameraExecutor?.Dispose();
-			cameraExecutor = null;
-
-			imageCapture?.Dispose();
-			imageCapture = null;
-
-			videoCapture?.Dispose();
-			videoCapture = null;
-
-			imageCallback?.Dispose();
-			imageCallback = null;
-
-			previewView?.Dispose();
-			previewView = null;
-
-			processCameraProvider?.Dispose();
-			processCameraProvider = null;
-
-			resolutionSelector?.Dispose();
-			resolutionSelector = null;
-
-			resolutionFilter?.Dispose();
-			resolutionFilter = null;
-
-			orientationListener?.Disable();
-			orientationListener?.Dispose();
-			orientationListener = null;
-
-			videoRecordingStream?.Dispose();
-			videoRecordingStream = null;
-		}
-	}
-
-	protected virtual async partial Task PlatformConnectCamera(CancellationToken token)
+	private async partial Task PlatformConnectCamera(CancellationToken token)
 	{
 		var cameraProviderFuture = ProcessCameraProvider.GetInstance(context);
 		if (previewView is null)
@@ -200,16 +191,6 @@ protected virtual async partial Task PlatformConnectCamera(CancellationToken tok
 		{
 			processCameraProvider = (ProcessCameraProvider)(cameraProviderFuture.Get() ?? throw new CameraException($"Unable to retrieve {nameof(ProcessCameraProvider)}"));
 
-			if (cameraProvider.AvailableCameras is null)
-			{
-				await cameraProvider.RefreshAvailableCameras(token);
-
-				if (cameraProvider.AvailableCameras is null)
-				{
-					throw new CameraException("Unable to refresh available cameras");
-				}
-			}
-
 			await StartUseCase(token);
 
 			cameraProviderTCS.SetResult();
@@ -218,7 +199,7 @@ protected virtual async partial Task PlatformConnectCamera(CancellationToken tok
 		await cameraProviderTCS.Task.WaitAsync(token);
 	}
 
-	protected async Task StartUseCase(CancellationToken token)
+	async Task StartUseCase(CancellationToken token)
 	{
 		if (resolutionSelector is null || cameraExecutor is null)
 		{
@@ -265,22 +246,14 @@ protected async Task StartUseCase(CancellationToken token)
 		await StartCameraPreview(token);
 	}
 
-	protected virtual async partial Task PlatformStartCameraPreview(CancellationToken token)
+	private async partial Task PlatformStartCameraPreview(CancellationToken token)
 	{
 		if (previewView is null || processCameraProvider is null || cameraPreview is null || imageCapture is null || videoCapture is null)
 		{
 			return;
 		}
 
-		if (cameraView.SelectedCamera is null)
-		{
-			if (cameraProvider.AvailableCameras is null)
-			{
-				await cameraProvider.RefreshAvailableCameras(token);
-			}
-
-			cameraView.SelectedCamera = cameraProvider.AvailableCameras?.FirstOrDefault() ?? throw new CameraException("No camera available on device");
-		}
+		cameraView.SelectedCamera ??= cameraProvider.AvailableCameras?.FirstOrDefault() ?? throw new CameraException("No camera available on device");
 
 		camera = await RebindCamera(processCameraProvider, cameraView.SelectedCamera, token, cameraPreview, imageCapture, videoCapture);
 		cameraControl = camera.CameraControl;
@@ -293,7 +266,7 @@ protected virtual async partial Task PlatformStartCameraPreview(CancellationToke
 		OnLoaded.Invoke();
 	}
 
-	protected virtual partial void PlatformStopCameraPreview()
+	private partial void PlatformStopCameraPreview()
 	{
 		if (processCameraProvider is null)
 		{
@@ -304,11 +277,11 @@ protected virtual partial void PlatformStopCameraPreview()
 		IsInitialized = false;
 	}
 
-	protected virtual partial void PlatformDisconnect()
+	private partial void PlatformDisconnect()
 	{
 	}
 
-	protected virtual partial ValueTask PlatformTakePicture(CancellationToken token)
+	private partial ValueTask PlatformTakePicture(CancellationToken token)
 	{
 		ArgumentNullException.ThrowIfNull(cameraExecutor);
 		ArgumentNullException.ThrowIfNull(imageCallback);
@@ -317,7 +290,7 @@ protected virtual partial ValueTask PlatformTakePicture(CancellationToken token)
 		return ValueTask.CompletedTask;
 	}
 
-	protected virtual async partial Task PlatformStartVideoRecording(Stream stream, CancellationToken token)
+	private async partial Task PlatformStartVideoRecording(Stream stream, CancellationToken token)
 	{
 		if (previewView is null
 			|| processCameraProvider is null
@@ -332,15 +305,7 @@ protected virtual async partial Task PlatformStartVideoRecording(Stream stream,
 
 		videoRecordingStream = stream;
 
-		if (cameraView.SelectedCamera is null)
-		{
-			if (cameraProvider.AvailableCameras is null)
-			{
-				await cameraProvider.RefreshAvailableCameras(token);
-			}
-
-			cameraView.SelectedCamera = cameraProvider.AvailableCameras?.FirstOrDefault() ?? throw new CameraException("No camera available on device");
-		}
+		cameraView.SelectedCamera ??= cameraProvider.AvailableCameras?.FirstOrDefault() ?? throw new CameraException("No camera available on device");
 
 		if (camera is null || !IsVideoCaptureAlreadyBound())
 		{
@@ -367,7 +332,7 @@ protected virtual async partial Task PlatformStartVideoRecording(Stream stream,
 		// https://developer.android.com/reference/androidx/camera/video/Recorder#prepareRecording(android.content.Context,androidx.camera.video.MediaStoreOutputOptions)
 	}
 
-	protected virtual async partial Task<Stream> PlatformStopVideoRecording(CancellationToken token)
+	private async partial Task<Stream> PlatformStopVideoRecording(CancellationToken token)
 	{
 		ArgumentNullException.ThrowIfNull(cameraExecutor);
 		if (videoRecording is null