PR Feedback

Microsoft.Maui.sln

@@ -200,6 +200,7 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MauiBlazorWebView.DeviceTes
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "SharedSource", "SharedSource", "{4F2926C8-43AB-4328-A735-D9EAD699F81D}"
 	ProjectSection(SolutionItems) = preProject
+		src\BlazorWebView\src\SharedSource\ExternalLinkMode.cs = src\BlazorWebView\src\SharedSource\ExternalLinkMode.cs
 		src\BlazorWebView\src\SharedSource\QueryStringHelper.cs = src\BlazorWebView\src\SharedSource\QueryStringHelper.cs
 		src\BlazorWebView\src\SharedSource\WebView2WebViewManager.cs = src\BlazorWebView\src\SharedSource\WebView2WebViewManager.cs
 	EndProjectSection

src/BlazorWebView/src/Maui/Android/AndroidWebKitWebViewManager.cs

@@ -18,9 +18,8 @@ public class AndroidWebKitWebViewManager : WebViewManager
 		// Using an IP address means that WebView doesn't wait for any DNS resolution,
 		// making it substantially faster. Note that this isn't real HTTP traffic, since
 		// we intercept all the requests within this origin.
-		private const string AppOrigin = "https://0.0.0.0/";
+		private static readonly string AppOrigin = $"https://{BlazorWebView.AppHostAddress}/";
 		private static readonly AUri AndroidAppOriginUri = AUri.Parse(AppOrigin)!;
-		private readonly BlazorWebViewHandler _blazorWebViewHandler;
 		private readonly AWebView _webview;
 
 		/// <summary>
@@ -31,11 +30,10 @@ public class AndroidWebKitWebViewManager : WebViewManager
 		/// <param name="dispatcher">A <see cref="Dispatcher"/> instance that can marshal calls to the required thread or sync context.</param>
 		/// <param name="fileProvider">Provides static content to the webview.</param>
 		/// <param name="hostPageRelativePath">Path to the host page within the <paramref name="fileProvider"/>.</param>
-		public AndroidWebKitWebViewManager(BlazorWebViewHandler blazorMauiWebViewHandler, AWebView webview, IServiceProvider services, Dispatcher dispatcher, IFileProvider fileProvider, JSComponentConfigurationStore jsComponents, string hostPageRelativePath)
+		public AndroidWebKitWebViewManager(AWebView webview!!, IServiceProvider services, Dispatcher dispatcher, IFileProvider fileProvider, JSComponentConfigurationStore jsComponents, string hostPageRelativePath)
 			: base(services, dispatcher, new Uri(AppOrigin), fileProvider, jsComponents, hostPageRelativePath)
 		{
-			_blazorWebViewHandler = blazorMauiWebViewHandler ?? throw new ArgumentNullException(nameof(blazorMauiWebViewHandler));
-			_webview = webview ?? throw new ArgumentNullException(nameof(webview));
+			_webview = webview;
 		}
 
 		/// <inheritdoc />

src/BlazorWebView/src/Maui/Android/BlazorWebViewHandler.Android.cs

@@ -88,7 +88,7 @@ private void StartWebViewCoreIfPossible()
 
 			var fileProvider = VirtualView.CreateFileProvider(contentRootDir);
 
-			_webviewManager = new AndroidWebKitWebViewManager(this, NativeView, Services!, ComponentsDispatcher, fileProvider, VirtualView.JSComponents, hostPageRelativePath);
+			_webviewManager = new AndroidWebKitWebViewManager(NativeView, Services!, ComponentsDispatcher, fileProvider, VirtualView.JSComponents, hostPageRelativePath);
 
 			if (RootComponents != null)
 			{

src/BlazorWebView/src/Maui/Android/WebKitWebViewClient.cs

@@ -9,13 +9,16 @@ namespace Microsoft.AspNetCore.Components.WebView.Maui
 {
 	internal class WebKitWebViewClient : WebViewClient
 	{
-		private const string AppOrigin = "https://0.0.0.0/";
+		// Using an IP address means that WebView doesn't wait for any DNS resolution,
+		// making it substantially faster. Note that this isn't real HTTP traffic, since
+		// we intercept all the requests within this origin.
+		private static readonly string AppOrigin = $"https://{BlazorWebView.AppHostAddress}/";
 
 		private readonly BlazorWebViewHandler? _webViewHandler;
 
-		public WebKitWebViewClient(BlazorWebViewHandler webViewHandler)
+		public WebKitWebViewClient(BlazorWebViewHandler webViewHandler!!)
 		{
-			_webViewHandler = webViewHandler ?? throw new ArgumentNullException(nameof(webViewHandler));
+			_webViewHandler = webViewHandler;
 		}
 
 		protected WebKitWebViewClient(IntPtr javaReference, JniHandleOwnership transfer) : base(javaReference, transfer)
@@ -34,7 +37,7 @@ public override bool ShouldOverrideUrlLoading(AWebView? view, IWebResourceReques
 			{
 				var uri = new Uri(requestUri);
 
-				if (uri.Host == "0.0.0.0" &&
+				if (uri.Host == BlazorWebView.AppHostAddress &&
 					view is not null && 
 					request is not null && 
 					request.IsRedirect && 
@@ -43,8 +46,8 @@ request is not null &&
 					view.LoadUrl(uri.ToString());
 					return true;
 				}
-				else if (uri.Host != "0.0.0.0" && 
-					_webViewHandler is not null &&
+				else if (uri.Host != BlazorWebView.AppHostAddress && 
+					_webViewHandler != null &&
 					_webViewHandler.ExternalLinkMode == ExternalLinkMode.OpenInExternalBrowser)
 				{
 					var intent = new Intent(Intent.ActionView, AUri.Parse(requestUri));
@@ -181,9 +184,9 @@ private class JavaScriptValueCallback : Java.Lang.Object, IValueCallback
 		{
 			private readonly Action _callback;
 
-			public JavaScriptValueCallback(Action callback)
+			public JavaScriptValueCallback(Action callback!!)
 			{
-				_callback = callback ?? throw new ArgumentNullException(nameof(callback));
+				_callback = callback;
 			}
 
 			public void OnReceiveValue(Java.Lang.Object? value)

src/BlazorWebView/src/Maui/BlazorWebView.cs

@@ -1,11 +1,13 @@
-using System;
-using Microsoft.AspNetCore.Components.Web;
+using Microsoft.AspNetCore.Components.Web;
+using Microsoft.AspNetCore.Components.WebView;
 using Microsoft.Extensions.FileProviders;
 
 namespace Microsoft.AspNetCore.Components.WebView.Maui
 {
 	public class BlazorWebView : Microsoft.Maui.Controls.View, IBlazorWebView
 	{
+		internal static readonly string AppHostAddress = "0.0.0.0";
+
 		private readonly JSComponentConfigurationStore _jSComponents = new();
 
 		public BlazorWebView()
@@ -19,6 +21,11 @@ public BlazorWebView()
 
 		public RootComponentsCollection RootComponents { get; }
 
+		/// <summary>
+		/// Specify whether links should be opened in the external
+		/// system default browser, or within the webview.
+		/// </summary>
+		/// <value>Defaults to opening links in the system default browser.</value>
 		public ExternalLinkMode ExternalLinkMode { get; set; } = ExternalLinkMode.OpenInExternalBrowser;
 
 		/// <inheritdoc/>

src/BlazorWebView/src/Maui/BlazorWebViewHandler.cs

@@ -1,15 +1,17 @@
 using System.Linq;
+using Microsoft.AspNetCore.Components.WebView;
 using Microsoft.Maui;
 using Microsoft.Maui.Handlers;
 
 namespace Microsoft.AspNetCore.Components.WebView.Maui
 {
 	public partial class BlazorWebViewHandler
 	{
-		public static PropertyMapper<IBlazorWebView, BlazorWebViewHandler> BlazorWebViewMapper = new(ViewMapper)
+		private static readonly PropertyMapper<IBlazorWebView, BlazorWebViewHandler> BlazorWebViewMapper = new(ViewMapper)
 		{
 			[nameof(IBlazorWebView.HostPage)] = MapHostPage,
 			[nameof(IBlazorWebView.RootComponents)] = MapRootComponents,
+			[nameof(IBlazorWebView.ExternalLinkMode)] = MapExternalLinkMode,
 		};
 
 		public BlazorWebViewHandler() : base(BlazorWebViewMapper)
@@ -28,7 +30,6 @@ public static void MapHostPage(BlazorWebViewHandler handler, IBlazorWebView webV
 		{
 #if !NETSTANDARD
 			handler.HostPage = webView.HostPage;
-			handler.ExternalLinkMode = webView.ExternalLinkMode;
 			handler.StartWebViewCoreIfPossible();
 #endif
 		}
@@ -37,6 +38,13 @@ public static void MapRootComponents(BlazorWebViewHandler handler, IBlazorWebVie
 		{
 #if !NETSTANDARD
 			handler.RootComponents = webView.RootComponents;
+			handler.StartWebViewCoreIfPossible();
+#endif
+		}
+
+		public static void MapExternalLinkMode(BlazorWebViewHandler handler, IBlazorWebView webView)
+		{
+#if !NETSTANDARD
 			handler.ExternalLinkMode = webView.ExternalLinkMode;
 			handler.StartWebViewCoreIfPossible();
 #endif

src/BlazorWebView/src/Maui/IBlazorWebView.cs

@@ -1,4 +1,5 @@
 using Microsoft.AspNetCore.Components.Web;
+using Microsoft.AspNetCore.Components.WebView;
 using Microsoft.Extensions.FileProviders;
 using Microsoft.Maui;
 
@@ -9,6 +10,11 @@ public interface IBlazorWebView : IView
 		string? HostPage { get; set; }
 		RootComponentsCollection RootComponents { get; }
 		JSComponentConfigurationStore JSComponents { get; }
+
+		/// <summary>
+		/// Specify whether links should be opened in the external
+		/// system default browser, or within the webview.
+		/// </summary>
 		ExternalLinkMode ExternalLinkMode { get; set; }
 
 		/// <summary>

src/BlazorWebView/src/Maui/Windows/BlazorWebViewHandler.Windows.cs

@@ -65,7 +65,7 @@ private void StartWebViewCoreIfPossible()
 				VirtualView.JSComponents,
 				hostPageRelativePath,
 				contentRootDir,
-				ExternalLinkMode);
+				this);
 
 			if (RootComponents != null)
 			{

src/BlazorWebView/src/Maui/Windows/WinUIWebViewManager.cs

@@ -22,25 +22,23 @@ public class WinUIWebViewManager : WebView2WebViewManager
 		private readonly WebView2Control _webview;
 		private readonly string _hostPageRelativePath;
 		private readonly string _contentRootDir;
-		private readonly ExternalLinkMode _externalLinkMode;
+		private readonly BlazorWebViewHandler _blazorWebViewHandler;
 
 		public WinUIWebViewManager(
-			WebView2Control webview!!,
+			WebView2Control webview,
 			IServiceProvider services,
 			Dispatcher dispatcher,
 			IFileProvider fileProvider,
 			JSComponentConfigurationStore jsComponents,
 			string hostPageRelativePath,
 			string contentRootDir,
-			ExternalLinkMode externalLinkMode)
+			BlazorWebViewHandler blazorWebViewHandler)
 			: base(webview, services, dispatcher, fileProvider, jsComponents, hostPageRelativePath)
 		{
 			_webview = webview;
 			_hostPageRelativePath = hostPageRelativePath;
 			_contentRootDir = contentRootDir;
-			_externalLinkMode = externalLinkMode;
-
-			_webview.CoreWebView2Initialized += Webview_CoreWebView2Initialized;
+			_blazorWebViewHandler = blazorWebViewHandler;
 		}
 
 		protected override async Task HandleWebResourceRequest(CoreWebView2WebResourceRequestedEventArgs eventArgs)
@@ -105,35 +103,18 @@ protected override async Task HandleWebResourceRequest(CoreWebView2WebResourceRe
 			deferral.Complete();
 		}
 
-		protected override void QueueBlazorStart()
-		{
-			// In .NET MAUI we use autostart='false' for the Blazor script reference, so we start it up manually in this event
-			_webview.CoreWebView2.DOMContentLoaded += async (_, __) =>
-			{
-				await _webview.CoreWebView2!.ExecuteScriptAsync(@"
-					Blazor.start();
-					");
-			};
-		}
-
-		private void Webview_CoreWebView2Initialized(WebView2Control sender, UI.Xaml.Controls.CoreWebView2InitializedEventArgs args)
-		{
-			_webview.CoreWebView2.NavigationStarting += CoreWebView2_NavigationStarting;
-			_webview.CoreWebView2.NewWindowRequested += CoreWebView2_NewWindowRequested;
-		}
-
-		private void CoreWebView2_NavigationStarting(CoreWebView2 sender, CoreWebView2NavigationStartingEventArgs args)
+		protected override void CoreWebView2_NavigationStarting(object sender, CoreWebView2NavigationStartingEventArgs args)
 		{
 			if (Uri.TryCreate(args.Uri, UriKind.RelativeOrAbsolute, out var uri) &&
-				uri.Host != "0.0.0.0" && 
-				_externalLinkMode == ExternalLinkMode.OpenInExternalBrowser)
+				uri.Host != AppHostAddress &&
+				_blazorWebViewHandler.ExternalLinkMode == ExternalLinkMode.OpenInExternalBrowser)
 			{
 				_ = Launcher.LaunchUriAsync(uri);
 				args.Cancel = true;
 			}
 		}
 
-		private void CoreWebView2_NewWindowRequested(CoreWebView2 sender, CoreWebView2NewWindowRequestedEventArgs args)
+		protected override void CoreWebView2_NewWindowRequested(object sender, CoreWebView2NewWindowRequestedEventArgs args)
 		{
 			// Intercept _blank target <a> tags to always open in device browser
 			// regardless of ExternalLinkMode.OpenInWebview
@@ -143,5 +124,16 @@ private void CoreWebView2_NewWindowRequested(CoreWebView2 sender, CoreWebView2Ne
 				args.Handled = true;
 			}
 		}
+
+		protected override void QueueBlazorStart()
+		{
+			// In .NET MAUI we use autostart='false' for the Blazor script reference, so we start it up manually in this event
+			_webview.CoreWebView2.DOMContentLoaded += async (_, __) =>
+			{
+				await _webview.CoreWebView2!.ExecuteScriptAsync(@"
+					Blazor.start();
+					");
+			};
+		}
 	}
 }

src/BlazorWebView/src/Maui/iOS/BlazorWebViewHandler.iOS.cs

@@ -22,7 +22,7 @@ public partial class BlazorWebViewHandler : ViewHandler<IBlazorWebView, WKWebVie
 	{
 		private IOSWebViewManager? _webviewManager;
 
-		private const string AppOrigin = "app://0.0.0.0/";
+		internal static readonly string AppOrigin = $"app://{BlazorWebView.AppHostAddress}/";
 		private const string BlazorInitScript = @"
 			window.__receiveMessageCallbacks = [];
 			window.__dispatchMessageCallback = function(message) {

src/BlazorWebView/src/Maui/iOS/IOSWebViewManager.cs

@@ -13,16 +13,14 @@ namespace Microsoft.AspNetCore.Components.WebView.Maui
 {
 	public class IOSWebViewManager : WebViewManager
 	{
-		private const string AppOrigin = "app://0.0.0.0/";
-
 		private readonly BlazorWebViewHandler _blazorMauiWebViewHandler;
 		private readonly WKWebView _webview;
 
-		public IOSWebViewManager(BlazorWebViewHandler blazorMauiWebViewHandler, WKWebView webview, IServiceProvider services, Dispatcher dispatcher, IFileProvider fileProvider, JSComponentConfigurationStore jsComponents, string hostPageRelativePath)
-			: base(services, dispatcher, new Uri(AppOrigin), fileProvider, jsComponents, hostPageRelativePath)
+		public IOSWebViewManager(BlazorWebViewHandler blazorMauiWebViewHandler!!, WKWebView webview!!, IServiceProvider services, Dispatcher dispatcher, IFileProvider fileProvider, JSComponentConfigurationStore jsComponents, string hostPageRelativePath)
+			: base(services, dispatcher, new Uri(BlazorWebViewHandler.AppOrigin), fileProvider, jsComponents, hostPageRelativePath)
 		{
-			_blazorMauiWebViewHandler = blazorMauiWebViewHandler ?? throw new ArgumentNullException(nameof(blazorMauiWebViewHandler));
-			_webview = webview ?? throw new ArgumentNullException(nameof(webview));
+			_blazorMauiWebViewHandler = blazorMauiWebViewHandler;
+			_webview = webview;
 
 			InitializeWebView();
 		}
@@ -204,7 +202,7 @@ public override void DidReceiveServerRedirectForProvisionalNavigation(WKWebView
 			{
 				// We need to intercept the redirects to the app scheme because Safari will block them.
 				// We will handle these redirects through the Navigation Manager.
-				if (_currentUri?.Host == "0.0.0.0")
+				if (_currentUri?.Host == BlazorWebView.AppHostAddress)
 				{
 					var uri = _currentUri;
 					_currentUri = null;

src/BlazorWebView/src/SharedSource/ExternalLinkMode.cs

@@ -0,0 +1,21 @@
+namespace Microsoft.AspNetCore.Components.WebView
+{
+	/// <summary>
+	/// Link handling mode for anchor tags <![CDATA[<a>]]> within a Blazor WebView.
+	/// 
+	/// `_blank` target links will always open in the default browser
+	/// regardless of this setting.
+	/// </summary>
+	public enum ExternalLinkMode
+	{
+		/// <summary>
+		/// Opens anchor tags <![CDATA[<a>]]> in the system default browser.
+		/// </summary>
+		OpenInExternalBrowser,
+
+		/// <summary>
+		/// Opens anchor tags <![CDATA[<a>]]> in the WebView. This is not recommended.
+		/// </summary>
+		OpenInWebView
+	}
+}