packages/webview_flutter/webview_flutter/lib/src/webview_controller.dart - mirrors/packages - Git at Google

 // Copyright 2013 The Flutter Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 import 'dart:typed_data';

 import 'package:flutter/material.dart';
 import 'package:webview_flutter_platform_interface/webview_flutter_platform_interface.dart';

 import 'navigation_delegate.dart';
 import 'webview_widget.dart';

 /// Controls a WebView provided by the host platform.
 ///
 /// Pass this to a [WebViewWidget] to display the WebView.
 ///
 /// A [WebViewController] can only be used by a single [WebViewWidget] at a
 /// time.
 ///
 /// ## Platform-Specific Features
 /// This class contains an underlying implementation provided by the current
 /// platform. Once a platform implementation is imported, the examples below
 /// can be followed to use features provided by a platform's implementation.
 ///
 /// {@macro webview_flutter.WebViewController.fromPlatformCreationParams}
 ///
 /// Below is an example of accessing the platform-specific implementation for
 /// iOS and Android:
 ///
 /// ```dart
 /// final WebViewController webViewController = WebViewController();
 ///
 /// if (WebViewPlatform.instance is WebKitWebViewPlatform) {
 ///   final WebKitWebViewController webKitController =
 ///       webViewController.platform as WebKitWebViewController;
 /// } else if (WebViewPlatform.instance is AndroidWebViewPlatform) {
 ///   final AndroidWebViewController androidController =
 ///       webViewController.platform as AndroidWebViewController;
 /// }
 /// ```
 class WebViewController {
   /// Constructs a [WebViewController].
   ///
   /// {@template webview_fluttter.WebViewController.constructor}
   /// `onPermissionRequest`: A callback that notifies the host application that
   /// web content is requesting permission to access the specified resources.
   /// To grant access for a device resource, most platforms will need to update
   /// their app configurations for the relevant system resource.
   ///
   /// For Android, you will need to update your `AndroidManifest.xml`. See
   /// https://developer.android.com/training/permissions/declaring
   ///
   /// For iOS, you will need to update your `Info.plist`. See
   /// https://developer.apple.com/documentation/uikit/protecting_the_user_s_privacy/requesting_access_to_protected_resources?language=objc.
   /// {@endtemplate}
   ///
   /// See [WebViewController.fromPlatformCreationParams] for setting parameters
   /// for a specific platform.
   WebViewController({
     void Function(WebViewPermissionRequest request)? onPermissionRequest,
   }) : this.fromPlatformCreationParams(
           const PlatformWebViewControllerCreationParams(),
           onPermissionRequest: onPermissionRequest,
         );

   /// Constructs a [WebViewController] from creation params for a specific
   /// platform.
   ///
   /// {@macro webview_fluttter.WebViewController.constructor}
   ///
   /// {@template webview_flutter.WebViewController.fromPlatformCreationParams}
   /// Below is an example of setting platform-specific creation parameters for
   /// iOS and Android:
   ///
   /// ```dart
   /// PlatformWebViewControllerCreationParams params =
   ///     const PlatformWebViewControllerCreationParams();
   ///
   /// if (WebViewPlatform.instance is WebKitWebViewPlatform) {
   ///   params = WebKitWebViewControllerCreationParams
   ///       .fromPlatformWebViewControllerCreationParams(
   ///     params,
   ///   );
   /// } else if (WebViewPlatform.instance is AndroidWebViewPlatform) {
   ///   params = AndroidWebViewControllerCreationParams
   ///       .fromPlatformWebViewControllerCreationParams(
   ///     params,
   ///   );
   /// }
   ///
   /// final WebViewController webViewController =
   ///     WebViewController.fromPlatformCreationParams(
   ///   params,
   /// );
   /// ```
   /// {@endtemplate}
   WebViewController.fromPlatformCreationParams(
     PlatformWebViewControllerCreationParams params, {
     void Function(WebViewPermissionRequest request)? onPermissionRequest,
   }) : this.fromPlatform(
           PlatformWebViewController(params),
           onPermissionRequest: onPermissionRequest,
         );

   /// Constructs a [WebViewController] from a specific platform implementation.
   ///
   /// {@macro webview_fluttter.WebViewController.constructor}
   WebViewController.fromPlatform(
     this.platform, {
     void Function(WebViewPermissionRequest request)? onPermissionRequest,
   }) {
     if (onPermissionRequest != null) {
       platform.setOnPlatformPermissionRequest(
         (PlatformWebViewPermissionRequest request) {
           onPermissionRequest(WebViewPermissionRequest._(
             request,
             types: request.types,
           ));
         },
       );
     }
   }

   /// Implementation of [PlatformWebViewController] for the current platform.
   final PlatformWebViewController platform;

   /// Loads the file located on the specified [absoluteFilePath].
   ///
   /// The [absoluteFilePath] parameter should contain the absolute path to the
   /// file as it is stored on the device. For example:
   /// `/Users/username/Documents/www/index.html`.
   ///
   /// Throws a `PlatformException` if the [absoluteFilePath] does not exist.
   Future<void> loadFile(String absoluteFilePath) {
     return platform.loadFile(absoluteFilePath);
   }

   /// Loads the Flutter asset specified in the pubspec.yaml file.
   ///
   /// Throws a `PlatformException` if [key] is not part of the specified assets
   /// in the pubspec.yaml file.
   Future<void> loadFlutterAsset(String key) {
     assert(key.isNotEmpty);
     return platform.loadFlutterAsset(key);
   }

   /// Loads the supplied HTML string.
   ///
   /// The [baseUrl] parameter is used when resolving relative URLs within the
   /// HTML string.
   Future<void> loadHtmlString(String html, {String? baseUrl}) {
     assert(html.isNotEmpty);
     return platform.loadHtmlString(html, baseUrl: baseUrl);
   }

   /// Makes a specific HTTP request and loads the response in the webview.
   ///
   /// [method] must be one of the supported HTTP methods in [LoadRequestMethod].
   ///
   /// If [headers] is not empty, its key-value pairs will be added as the
   /// headers for the request.
   ///
   /// If [body] is not null, it will be added as the body for the request.
   ///
   /// Throws an ArgumentError if [uri] has an empty scheme.
   Future<void> loadRequest(
     Uri uri, {
     LoadRequestMethod method = LoadRequestMethod.get,
     Map<String, String> headers = const <String, String>{},
     Uint8List? body,
   }) {
     if (uri.scheme.isEmpty) {
       throw ArgumentError('Missing scheme in uri: $uri');
     }
     return platform.loadRequest(LoadRequestParams(
       uri: uri,
       method: method,
       headers: headers,
       body: body,
     ));
   }

   /// Returns the current URL that the WebView is displaying.
   ///
   /// If no URL was ever loaded, returns `null`.
   Future<String?> currentUrl() {
     return platform.currentUrl();
   }

   /// Checks whether there's a back history item.
   Future<bool> canGoBack() {
     return platform.canGoBack();
   }

   /// Checks whether there's a forward history item.
   Future<bool> canGoForward() {
     return platform.canGoForward();
   }

   /// Goes back in the history of this WebView.
   ///
   /// If there is no back history item this is a no-op.
   Future<void> goBack() {
     return platform.goBack();
   }

   /// Goes forward in the history of this WebView.
   ///
   /// If there is no forward history item this is a no-op.
   Future<void> goForward() {
     return platform.goForward();
   }

   /// Reloads the current URL.
   Future<void> reload() {
     return platform.reload();
   }

   /// Sets the [NavigationDelegate] containing the callback methods that are
   /// called during navigation events.
   Future<void> setNavigationDelegate(NavigationDelegate delegate) {
     return platform.setPlatformNavigationDelegate(delegate.platform);
   }

   /// Clears all caches used by the WebView.
   ///
   /// The following caches are cleared:
   ///	1. Browser HTTP Cache.
   ///	2. [Cache API](https://developers.google.com/web/fundamentals/instant-and-offline/web-storage/cache-api)
   ///    caches. Service workers tend to use this cache.
   ///	3. Application cache.
   Future<void> clearCache() {
     return platform.clearCache();
   }

   /// Clears the local storage used by the WebView.
   Future<void> clearLocalStorage() {
     return platform.clearLocalStorage();
   }

   /// Runs the given JavaScript in the context of the current page.
   ///
   /// The Future completes with an error if a JavaScript error occurred.
   Future<void> runJavaScript(String javaScript) {
     return platform.runJavaScript(javaScript);
   }

   /// Runs the given JavaScript in the context of the current page, and returns
   /// the result.
   ///
   /// The Future completes with an error if a JavaScript error occurred, or if
   /// the type the given expression evaluates to is unsupported. Unsupported
   /// values include certain non-primitive types on iOS, as well as `undefined`
   /// or `null` on iOS 14+.
   Future<Object> runJavaScriptReturningResult(String javaScript) {
     return platform.runJavaScriptReturningResult(javaScript);
   }

   /// Adds a new JavaScript channel to the set of enabled channels.
   ///
   /// The JavaScript code can then call `postMessage` on that object to send a
   /// message that will be passed to [onMessageReceived].
   ///
   /// For example, after adding the following JavaScript channel:
   ///
   /// ```dart
   /// final WebViewController controller = WebViewController();
   /// controller.addJavaScriptChannel(
   ///   'Print',
   ///   onMessageReceived: (JavaScriptMessage message) {
   ///     print(message.message);
   ///   },
   /// );
   /// ```
   ///
   /// JavaScript code can call:
   ///
   /// ```javascript
   /// Print.postMessage('Hello');
   /// ```
   ///
   /// to asynchronously invoke the message handler which will print the message
   /// to standard output.
   ///
   /// Adding a new JavaScript channel only takes effect after the next page is
   /// loaded.
   ///
   /// A channel [name] cannot be the same for multiple channels.
   Future<void> addJavaScriptChannel(
     String name, {
     required void Function(JavaScriptMessage) onMessageReceived,
   }) {
     assert(name.isNotEmpty);
     return platform.addJavaScriptChannel(JavaScriptChannelParams(
       name: name,
       onMessageReceived: onMessageReceived,
     ));
   }

   /// Removes the JavaScript channel with the matching name from the set of
   /// enabled channels.
   ///
   /// This disables the channel with the matching name if it was previously
   /// enabled through the [addJavaScriptChannel].
   Future<void> removeJavaScriptChannel(String javaScriptChannelName) {
     return platform.removeJavaScriptChannel(javaScriptChannelName);
   }

   /// The title of the currently loaded page.
   Future<String?> getTitle() {
     return platform.getTitle();
   }

   /// Sets the scrolled position of this view.
   ///
   /// The parameters `x` and `y` specify the position to scroll to in WebView
   /// pixels.
   Future<void> scrollTo(int x, int y) {
     return platform.scrollTo(x, y);
   }

   /// Moves the scrolled position of this view.
   ///
   /// The parameters `x` and `y` specify the amount of WebView pixels to scroll
   /// by.
   Future<void> scrollBy(int x, int y) {
     return platform.scrollBy(x, y);
   }

   /// Returns the current scroll position of this view.
   ///
   /// Scroll position is measured from the top left.
   Future<Offset> getScrollPosition() {
     return platform.getScrollPosition();
   }

   /// Whether to support zooming using the on-screen zoom controls and gestures.
   Future<void> enableZoom(bool enabled) {
     return platform.enableZoom(enabled);
   }

   /// Sets the current background color of this view.
   Future<void> setBackgroundColor(Color color) {
     return platform.setBackgroundColor(color);
   }

   /// Sets the JavaScript execution mode to be used by the WebView.
   Future<void> setJavaScriptMode(JavaScriptMode javaScriptMode) {
     return platform.setJavaScriptMode(javaScriptMode);
   }

   /// Sets the value used for the HTTP `User-Agent:` request header.
   Future<void> setUserAgent(String? userAgent) {
     return platform.setUserAgent(userAgent);
   }

   /// Sets a callback that notifies the host application on any log messages
   /// written to the JavaScript console.
   ///
   /// Platforms may not preserve all the log level information so clients should
   /// not rely on a 1:1 mapping between the JavaScript calls.
   ///
   /// On iOS setting this callback will inject a custom [WKUserScript] which
   /// overrides the default implementation of `console.debug`, `console.error`,
   /// `console.info`, `console.log` and `console.warning` methods. The iOS
   /// WebKit framework unfortunately doesn't provide a built-in method to
   /// forward console messages.
   Future<void> setOnConsoleMessage(
       void Function(JavaScriptConsoleMessage message) onConsoleMessage) {
     return platform.setOnConsoleMessage(onConsoleMessage);
   }

   /// Gets the value used for the HTTP `User-Agent:` request header.
   Future<String?> getUserAgent() {
     return platform.getUserAgent();
   }
 }

 /// Permissions request when web content requests access to protected resources.
 ///
 /// A response MUST be provided by calling [grant], [deny], or a method from
 /// [platform].
 ///
 /// ## Platform-Specific Features
 /// This class contains an underlying implementation provided by the current
 /// platform. Once a platform implementation is imported, the example below
 /// can be followed to use features provided by a platform's implementation.
 ///
 /// Below is an example of accessing the platform-specific implementation for
 /// iOS and Android:
 ///
 /// ```dart
 /// final WebViewPermissionRequest request = ...;
 ///
 /// if (WebViewPlatform.instance is WebKitWebViewPlatform) {
 ///   final WebKitWebViewPermissionRequest webKitRequest =
 ///       request.platform as WebKitWebViewPermissionRequest;
 /// } else if (WebViewPlatform.instance is AndroidWebViewPlatform) {
 ///   final AndroidWebViewPermissionRequest androidRequest =
 ///       request.platform as AndroidWebViewPermissionRequest;
 /// }
 /// ```
 @immutable
 class WebViewPermissionRequest {
   const WebViewPermissionRequest._(this.platform, {required this.types});

   /// All resources access has been requested for.
   final Set<WebViewPermissionResourceType> types;

   /// Implementation of [PlatformWebViewPermissionRequest] for the current
   /// platform.
   final PlatformWebViewPermissionRequest platform;

   /// Grant permission for the requested resource(s).
   Future<void> grant() {
     return platform.grant();
   }

   /// Deny permission for the requested resource(s).
   Future<void> deny() {
     return platform.deny();
   }
 }
	// Copyright 2013 The Flutter Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	import 'dart:typed_data';

	import 'package:flutter/material.dart';
	import 'package:webview_flutter_platform_interface/webview_flutter_platform_interface.dart';

	import 'navigation_delegate.dart';
	import 'webview_widget.dart';

	/// Controls a WebView provided by the host platform.
	///
	/// Pass this to a [WebViewWidget] to display the WebView.
	///
	/// A [WebViewController] can only be used by a single [WebViewWidget] at a
	/// time.
	///
	/// ## Platform-Specific Features
	/// This class contains an underlying implementation provided by the current
	/// platform. Once a platform implementation is imported, the examples below
	/// can be followed to use features provided by a platform's implementation.
	///
	/// {@macro webview_flutter.WebViewController.fromPlatformCreationParams}
	///
	/// Below is an example of accessing the platform-specific implementation for
	/// iOS and Android:
	///
	/// ```dart
	/// final WebViewController webViewController = WebViewController();
	///
	/// if (WebViewPlatform.instance is WebKitWebViewPlatform) {
	/// final WebKitWebViewController webKitController =
	/// webViewController.platform as WebKitWebViewController;
	/// } else if (WebViewPlatform.instance is AndroidWebViewPlatform) {
	/// final AndroidWebViewController androidController =
	/// webViewController.platform as AndroidWebViewController;
	/// }
	/// ```
	class WebViewController {
	/// Constructs a [WebViewController].
	///
	/// {@template webview_fluttter.WebViewController.constructor}
	/// `onPermissionRequest`: A callback that notifies the host application that
	/// web content is requesting permission to access the specified resources.
	/// To grant access for a device resource, most platforms will need to update
	/// their app configurations for the relevant system resource.
	///
	/// For Android, you will need to update your `AndroidManifest.xml`. See
	/// https://developer.android.com/training/permissions/declaring
	///
	/// For iOS, you will need to update your `Info.plist`. See
	/// https://developer.apple.com/documentation/uikit/protecting_the_user_s_privacy/requesting_access_to_protected_resources?language=objc.
	/// {@endtemplate}
	///
	/// See [WebViewController.fromPlatformCreationParams] for setting parameters
	/// for a specific platform.
	WebViewController({
	void Function(WebViewPermissionRequest request)? onPermissionRequest,
	}) : this.fromPlatformCreationParams(
	const PlatformWebViewControllerCreationParams(),
	onPermissionRequest: onPermissionRequest,
	);

	/// Constructs a [WebViewController] from creation params for a specific
	/// platform.
	///
	/// {@macro webview_fluttter.WebViewController.constructor}
	///
	/// {@template webview_flutter.WebViewController.fromPlatformCreationParams}
	/// Below is an example of setting platform-specific creation parameters for
	/// iOS and Android:
	///
	/// ```dart
	/// PlatformWebViewControllerCreationParams params =
	/// const PlatformWebViewControllerCreationParams();
	///
	/// if (WebViewPlatform.instance is WebKitWebViewPlatform) {
	/// params = WebKitWebViewControllerCreationParams
	/// .fromPlatformWebViewControllerCreationParams(
	/// params,
	/// );
	/// } else if (WebViewPlatform.instance is AndroidWebViewPlatform) {
	/// params = AndroidWebViewControllerCreationParams
	/// .fromPlatformWebViewControllerCreationParams(
	/// params,
	/// );
	/// }
	///
	/// final WebViewController webViewController =
	/// WebViewController.fromPlatformCreationParams(
	/// params,
	/// );
	/// ```
	/// {@endtemplate}
	WebViewController.fromPlatformCreationParams(
	PlatformWebViewControllerCreationParams params, {
	void Function(WebViewPermissionRequest request)? onPermissionRequest,
	}) : this.fromPlatform(
	PlatformWebViewController(params),
	onPermissionRequest: onPermissionRequest,
	);

	/// Constructs a [WebViewController] from a specific platform implementation.
	///
	/// {@macro webview_fluttter.WebViewController.constructor}
	WebViewController.fromPlatform(
	this.platform, {
	void Function(WebViewPermissionRequest request)? onPermissionRequest,
	}) {
	if (onPermissionRequest != null) {
	platform.setOnPlatformPermissionRequest(
	(PlatformWebViewPermissionRequest request) {
	onPermissionRequest(WebViewPermissionRequest._(
	request,
	types: request.types,
	));
	},
	);
	}
	}

	/// Implementation of [PlatformWebViewController] for the current platform.
	final PlatformWebViewController platform;

	/// Loads the file located on the specified [absoluteFilePath].
	///
	/// The [absoluteFilePath] parameter should contain the absolute path to the
	/// file as it is stored on the device. For example:
	/// `/Users/username/Documents/www/index.html`.
	///
	/// Throws a `PlatformException` if the [absoluteFilePath] does not exist.
	Future<void> loadFile(String absoluteFilePath) {
	return platform.loadFile(absoluteFilePath);
	}

	/// Loads the Flutter asset specified in the pubspec.yaml file.
	///
	/// Throws a `PlatformException` if [key] is not part of the specified assets
	/// in the pubspec.yaml file.
	Future<void> loadFlutterAsset(String key) {
	assert(key.isNotEmpty);
	return platform.loadFlutterAsset(key);
	}

	/// Loads the supplied HTML string.
	///
	/// The [baseUrl] parameter is used when resolving relative URLs within the
	/// HTML string.
	Future<void> loadHtmlString(String html, {String? baseUrl}) {
	assert(html.isNotEmpty);
	return platform.loadHtmlString(html, baseUrl: baseUrl);
	}

	/// Makes a specific HTTP request and loads the response in the webview.
	///
	/// [method] must be one of the supported HTTP methods in [LoadRequestMethod].
	///
	/// If [headers] is not empty, its key-value pairs will be added as the
	/// headers for the request.
	///
	/// If [body] is not null, it will be added as the body for the request.
	///
	/// Throws an ArgumentError if [uri] has an empty scheme.
	Future<void> loadRequest(
	Uri uri, {
	LoadRequestMethod method = LoadRequestMethod.get,
	Map<String, String> headers = const <String, String>{},
	Uint8List? body,
	}) {
	if (uri.scheme.isEmpty) {
	throw ArgumentError('Missing scheme in uri: $uri');
	}
	return platform.loadRequest(LoadRequestParams(
	uri: uri,
	method: method,
	headers: headers,
	body: body,
	));
	}

	/// Returns the current URL that the WebView is displaying.
	///
	/// If no URL was ever loaded, returns `null`.
	Future<String?> currentUrl() {
	return platform.currentUrl();
	}

	/// Checks whether there's a back history item.
	Future<bool> canGoBack() {
	return platform.canGoBack();
	}

	/// Checks whether there's a forward history item.
	Future<bool> canGoForward() {
	return platform.canGoForward();
	}

	/// Goes back in the history of this WebView.
	///
	/// If there is no back history item this is a no-op.
	Future<void> goBack() {
	return platform.goBack();
	}

	/// Goes forward in the history of this WebView.
	///
	/// If there is no forward history item this is a no-op.
	Future<void> goForward() {
	return platform.goForward();
	}

	/// Reloads the current URL.
	Future<void> reload() {
	return platform.reload();
	}

	/// Sets the [NavigationDelegate] containing the callback methods that are
	/// called during navigation events.
	Future<void> setNavigationDelegate(NavigationDelegate delegate) {
	return platform.setPlatformNavigationDelegate(delegate.platform);
	}

	/// Clears all caches used by the WebView.
	///
	/// The following caches are cleared:
	/// 1. Browser HTTP Cache.
	/// 2. [Cache API](https://developers.google.com/web/fundamentals/instant-and-offline/web-storage/cache-api)
	/// caches. Service workers tend to use this cache.
	/// 3. Application cache.
	Future<void> clearCache() {
	return platform.clearCache();
	}

	/// Clears the local storage used by the WebView.
	Future<void> clearLocalStorage() {
	return platform.clearLocalStorage();
	}

	/// Runs the given JavaScript in the context of the current page.
	///
	/// The Future completes with an error if a JavaScript error occurred.
	Future<void> runJavaScript(String javaScript) {
	return platform.runJavaScript(javaScript);
	}

	/// Runs the given JavaScript in the context of the current page, and returns
	/// the result.
	///
	/// The Future completes with an error if a JavaScript error occurred, or if
	/// the type the given expression evaluates to is unsupported. Unsupported
	/// values include certain non-primitive types on iOS, as well as `undefined`
	/// or `null` on iOS 14+.
	Future<Object> runJavaScriptReturningResult(String javaScript) {
	return platform.runJavaScriptReturningResult(javaScript);
	}

	/// Adds a new JavaScript channel to the set of enabled channels.
	///
	/// The JavaScript code can then call `postMessage` on that object to send a
	/// message that will be passed to [onMessageReceived].
	///
	/// For example, after adding the following JavaScript channel:
	///
	/// ```dart
	/// final WebViewController controller = WebViewController();
	/// controller.addJavaScriptChannel(
	/// 'Print',
	/// onMessageReceived: (JavaScriptMessage message) {
	/// print(message.message);
	/// },
	/// );
	/// ```
	///
	/// JavaScript code can call:
	///
	/// ```javascript
	/// Print.postMessage('Hello');
	/// ```
	///
	/// to asynchronously invoke the message handler which will print the message
	/// to standard output.
	///
	/// Adding a new JavaScript channel only takes effect after the next page is
	/// loaded.
	///
	/// A channel [name] cannot be the same for multiple channels.
	Future<void> addJavaScriptChannel(
	String name, {
	required void Function(JavaScriptMessage) onMessageReceived,
	}) {
	assert(name.isNotEmpty);
	return platform.addJavaScriptChannel(JavaScriptChannelParams(
	name: name,
	onMessageReceived: onMessageReceived,
	));
	}

	/// Removes the JavaScript channel with the matching name from the set of
	/// enabled channels.
	///
	/// This disables the channel with the matching name if it was previously
	/// enabled through the [addJavaScriptChannel].
	Future<void> removeJavaScriptChannel(String javaScriptChannelName) {
	return platform.removeJavaScriptChannel(javaScriptChannelName);
	}

	/// The title of the currently loaded page.
	Future<String?> getTitle() {
	return platform.getTitle();
	}

	/// Sets the scrolled position of this view.
	///
	/// The parameters `x` and `y` specify the position to scroll to in WebView
	/// pixels.
	Future<void> scrollTo(int x, int y) {
	return platform.scrollTo(x, y);
	}

	/// Moves the scrolled position of this view.
	///
	/// The parameters `x` and `y` specify the amount of WebView pixels to scroll
	/// by.
	Future<void> scrollBy(int x, int y) {
	return platform.scrollBy(x, y);
	}

	/// Returns the current scroll position of this view.
	///
	/// Scroll position is measured from the top left.
	Future<Offset> getScrollPosition() {
	return platform.getScrollPosition();
	}

	/// Whether to support zooming using the on-screen zoom controls and gestures.
	Future<void> enableZoom(bool enabled) {
	return platform.enableZoom(enabled);
	}

	/// Sets the current background color of this view.
	Future<void> setBackgroundColor(Color color) {
	return platform.setBackgroundColor(color);
	}

	/// Sets the JavaScript execution mode to be used by the WebView.
	Future<void> setJavaScriptMode(JavaScriptMode javaScriptMode) {
	return platform.setJavaScriptMode(javaScriptMode);
	}

	/// Sets the value used for the HTTP `User-Agent:` request header.
	Future<void> setUserAgent(String? userAgent) {
	return platform.setUserAgent(userAgent);
	}

	/// Sets a callback that notifies the host application on any log messages
	/// written to the JavaScript console.
	///
	/// Platforms may not preserve all the log level information so clients should
	/// not rely on a 1:1 mapping between the JavaScript calls.
	///
	/// On iOS setting this callback will inject a custom [WKUserScript] which
	/// overrides the default implementation of `console.debug`, `console.error`,
	/// `console.info`, `console.log` and `console.warning` methods. The iOS
	/// WebKit framework unfortunately doesn't provide a built-in method to
	/// forward console messages.
	Future<void> setOnConsoleMessage(
	void Function(JavaScriptConsoleMessage message) onConsoleMessage) {
	return platform.setOnConsoleMessage(onConsoleMessage);
	}

	/// Gets the value used for the HTTP `User-Agent:` request header.
	Future<String?> getUserAgent() {
	return platform.getUserAgent();
	}
	}

	/// Permissions request when web content requests access to protected resources.
	///
	/// A response MUST be provided by calling [grant], [deny], or a method from
	/// [platform].
	///
	/// ## Platform-Specific Features
	/// This class contains an underlying implementation provided by the current
	/// platform. Once a platform implementation is imported, the example below
	/// can be followed to use features provided by a platform's implementation.
	///
	/// Below is an example of accessing the platform-specific implementation for
	/// iOS and Android:
	///
	/// ```dart
	/// final WebViewPermissionRequest request = ...;
	///
	/// if (WebViewPlatform.instance is WebKitWebViewPlatform) {
	/// final WebKitWebViewPermissionRequest webKitRequest =
	/// request.platform as WebKitWebViewPermissionRequest;
	/// } else if (WebViewPlatform.instance is AndroidWebViewPlatform) {
	/// final AndroidWebViewPermissionRequest androidRequest =
	/// request.platform as AndroidWebViewPermissionRequest;
	/// }
	/// ```
	@immutable
	class WebViewPermissionRequest {
	const WebViewPermissionRequest._(this.platform, {required this.types});

	/// All resources access has been requested for.
	final Set<WebViewPermissionResourceType> types;

	/// Implementation of [PlatformWebViewPermissionRequest] for the current
	/// platform.
	final PlatformWebViewPermissionRequest platform;

	/// Grant permission for the requested resource(s).
	Future<void> grant() {
	return platform.grant();
	}

	/// Deny permission for the requested resource(s).
	Future<void> deny() {
	return platform.deny();
	}
	}