///Flutter Widget for adding an **inline native WebView** integrated in the flutter widget tree.
///
///All platforms support these options:
/// - __useShouldOverrideUrlLoading__: Set to `true` to be able to listen at the [InAppWebView.shouldOverrideUrlLoading()] event. The default value is `false`.
/// - __useOnLoadResource__: Set to `true` to be able to listen at the [InAppWebView.onLoadResource()] event. The default value is `false`.
/// - __useOnTargetBlank__: Set to `true` to be able to listen at the [InAppWebView.onTargetBlank()] event. The default value is `false`.
/// - __clearCache__: Set to `true` to have all the browser's cache cleared before the new window is opened. The default value is `false`.
/// - __userAgent___: Set the custom WebView's user-agent.
/// - __javaScriptEnabled__: Set to `true` to enable JavaScript. The default value is `true`.
/// - __javaScriptCanOpenWindowsAutomatically__: Set to `true` to allow JavaScript open windows without user interaction. The default value is `false`.
/// - __mediaPlaybackRequiresUserGesture__: Set to `true` to prevent HTML5 audio or video from autoplaying. The default value is `true`.
/// - __transparentBackground__: Set to `true` to make the background of the WebView transparent. If your app has a dark theme, this can prevent a white flash on initialization. The default value is `false`.
/// - __resourceCustomSchemes__: List of custom schemes that [InAppWebView] must handle. Use the [InAppWebView.onLoadResourceCustomScheme()] event to intercept resource requests with custom scheme.
///
/// **Android** supports these additional options:
///
/// - __clearSessionCache__: Set to `true` to have the session cookie cache cleared before the new window is opened.
/// - __builtInZoomControls__: Set to `true` if the WebView should use its built-in zoom mechanisms. The default value is `false`.
/// - __displayZoomControls__: Set to `true` if the WebView should display on-screen zoom controls when using the built-in zoom mechanisms. The default value is `false`.
/// - __supportZoom__: Set to `false` if the WebView should not support zooming using its on-screen zoom controls and gestures. The default value is `true`.
/// - __databaseEnabled__: Set to `true` if you want the database storage API is enabled. The default value is `false`.
/// - __domStorageEnabled__: Set to `true` if you want the DOM storage API is enabled. The default value is `false`.
/// - __useWideViewPort__: Set to `true` if the WebView should enable support for the "viewport" HTML meta tag or should use a wide viewport. When the value of the setting is false, the layout width is always set to the width of the WebView control in device-independent (CSS) pixels. When the value is true and the page contains the viewport meta tag, the value of the width specified in the tag is used. If the page does not contain the tag or does not provide a width, then a wide viewport will be used. The default value is `true`.
/// - __safeBrowsingEnabled__: Set to `true` if you want the Safe Browsing is enabled. Safe Browsing allows WebView to protect against malware and phishing attacks by verifying the links. The default value is `true`.
/// - __textZoom__: Set text scaling of the WebView. The default value is `100`.
/// - __mixedContentMode__: Configures the WebView's behavior when a secure origin attempts to load a resource from an insecure origin. By default, apps that target `Build.VERSION_CODES.KITKAT` or below default to `MIXED_CONTENT_ALWAYS_ALLOW`. Apps targeting `Build.VERSION_CODES.LOLLIPOP` default to `MIXED_CONTENT_NEVER_ALLOW`. The preferred and most secure mode of operation for the WebView is `MIXED_CONTENT_NEVER_ALLOW` and use of `MIXED_CONTENT_ALWAYS_ALLOW` is strongly discouraged.
///
/// **iOS** supports these additional options:
///
/// - __disallowOverScroll__: Set to `true` to disable the bouncing of the WebView when the scrolling has reached an edge of the content. The default value is `false`.
/// - __enableViewportScale__: Set to `true` to allow a viewport meta tag to either disable or restrict the range of user scaling. The default value is `false`.
/// - __suppressesIncrementalRendering__: Set to `true` if you want the WebView suppresses content rendering until it is fully loaded into memory.. The default value is `false`.
/// - __allowsAirPlayForMediaPlayback__: Set to `true` to allow AirPlay. The default value is `true`.
/// - __allowsBackForwardNavigationGestures__: Set to `true` to allow the horizontal swipe gestures trigger back-forward list navigations. The default value is `true`.
/// - __allowsLinkPreview__: Set to `true` to allow that pressing on a link displays a preview of the destination for the link. The default value is `true`.
/// - __ignoresViewportScaleLimits__: Set to `true` if you want that the WebView should always allow scaling of the webpage, regardless of the author's intent. The ignoresViewportScaleLimits property overrides the `user-scalable` HTML property in a webpage. The default value is `false`.
/// - __allowsInlineMediaPlayback__: Set to `true` to allow HTML5 media playback to appear inline within the screen layout, using browser-supplied controls rather than native controls. For this to work, add the `webkit-playsinline` attribute to any `<video>` elements. The default value is `false`.
/// - __allowsPictureInPictureMediaPlayback__: Set to `true` to allow HTML5 videos play picture-in-picture. The default value is `true`.
classInAppWebViewextendsStatefulWidget{
///Event fires when the [InAppWebView] is created.
finalonWebViewCreatedCallbackonWebViewCreated;
///Event fires when the [InAppWebView] starts to load an [url].
finalonWebViewLoadStartCallbackonLoadStart;
///Event fires when the [InAppWebView] finishes loading an [url].
finalonWebViewLoadStopCallbackonLoadStop;
///Event fires when the [InAppWebView] encounters an error loading an [url].
finalonWebViewLoadErrorCallbackonLoadError;
///Event fires when the current [progress] of loading a page is changed.
///Event fires when [InAppWebView] recognizes and starts a downloadable file.
///[url] represents the url of the file.
finalonDownloadStartCallbackonDownloadStart;
///Event fires when the [InAppWebView] finds the `custom-scheme` while loading a resource. Here you can handle the url request and return a [CustomSchemeResponse] to load a specific resource encoded to `base64`.
///Event that notifies the host application that web content from the specified origin is attempting to use the Geolocation API, but no permission state is currently set for that origin.
///Note that for applications targeting Android N and later SDKs (API level > `Build.VERSION_CODES.M`) this method is only called for requests originating from secure origins such as https.
///On non-secure origins geolocation requests are automatically denied.
///[origin] represents the origin of the web content attempting to use the Geolocation API.
///This is not always the same as the URL passed to [InAppWebView.onLoadStarted] because although the load for that URL has begun, the current page may not have changed.
///Loads the given [assetFilePath] with optional [headers] specified as a map from name to value.
///
///To be able to load your local files (assets, js, css, etc.), you need to add them in the `assets` section of the `pubspec.yaml` file, otherwise they cannot be found!
///
///Example of a `pubspec.yaml` file:
///```yaml
///...
///
///# The following section is specific to Flutter.
///flutter:
///
/// # The following line ensures that the Material Icons font is
/// # included with your application, so that you can use the icons in
///Returns a boolean value indicating whether the [InAppWebView] can go back or forward the given number of steps. Steps is negative if backward and positive if forward.
///Adds a JavaScript message handler [callback] ([JavaScriptHandlerCallback]) that listen to post messages sent from JavaScript by the handler with name [handlerName].
///The JavaScript function that can be used to call the handler is `window.flutter_inappbrowser.callHandler(handlerName <String>, ...args)`, where `args` are [rest parameters](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/rest_parameters).
///The `args` will be stringified automatically using `JSON.stringify(args)` method and then they will be decoded on the Dart side.
///
///In order to call `window.flutter_inappbrowser.callHandler(handlerName <String>, ...args)` properly, you need to wait and listen the JavaScript event `flutterInAppBrowserPlatformReady`.
///This event will be dispatch as soon as the platform (Android or iOS) is ready to handle the `callHandler` method.
///`window.flutter_inappbrowser.callHandler` returns a JavaScript [Promise](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise)
///that can be used to get the json result returned by [JavaScriptHandlerCallback].
///In this case, simply return data that you want to send and it will be automatically json encoded using [jsonEncode] from the `dart:convert` library.
///
///So, on the JavaScript side, to get data coming from the Dart side, you will use:
