public class

WebViewCompat

extends java.lang.Object

 java.lang.Object

↳androidx.webkit.WebViewCompat

Gradle dependencies

compile group: 'androidx.webkit', name: 'webkit', version: '1.5.0-alpha01'

  • groupId: androidx.webkit
  • artifactId: webkit
  • version: 1.5.0-alpha01

Artifact androidx.webkit:webkit:1.5.0-alpha01 it located at Google repository (https://maven.google.com/)

Androidx artifact mapping:

androidx.webkit:webkit com.android.support:webkit

Overview

Compatibility version of

Summary

Methods
public static ScriptHandleraddDocumentStartJavaScript(WebView webview, java.lang.String script, java.util.Set<java.lang.String> allowedOriginRules)

Adds a JavaScript script to the which will be executed in any frame whose origin matches allowedOriginRules when the document begins to load.

public static voidaddWebMessageListener(WebView webView, java.lang.String jsObjectName, java.util.Set<java.lang.String> allowedOriginRules, WebViewCompat.WebMessageListener listener)

Adds a WebViewCompat.WebMessageListener to the and injects a JavaScript object into each frame that the WebViewCompat.WebMessageListener will listen on.

public static WebMessagePortCompatcreateWebMessageChannel(WebView webview)

Creates a message channel to communicate with JS and returns the message ports that represent the endpoints of this message channel.

public static PackageInfogetCurrentWebViewPackage(Context context)

If WebView has already been loaded into the current process this method will return the package that was used to load it.

public static UrigetSafeBrowsingPrivacyPolicyUrl()

Returns a URL pointing to the privacy policy for Safe Browsing reporting.

public static java.lang.StringgetVariationsHeader()

Gets the WebView variations encoded to be used as the X-Client-Data HTTP header.

public static WebChromeClientgetWebChromeClient(WebView webview)

Gets the WebChromeClient.

public static WebViewClientgetWebViewClient(WebView webview)

Gets the WebViewClient for the WebView argument.

public static WebViewRenderProcessgetWebViewRenderProcess(WebView webview)

Gets the WebView renderer associated with this WebView.

public static WebViewRenderProcessClientgetWebViewRenderProcessClient(WebView webview)

Gets the renderer client object associated with this WebView.

public static booleanisMultiProcessEnabled()

Returns true if is running in multi process mode.

public static voidpostVisualStateCallback(WebView webview, long requestId, WebViewCompat.VisualStateCallback callback)

Posts a WebViewCompat.VisualStateCallback, which will be called when the current state of the WebView is ready to be drawn.

public static voidpostWebMessage(WebView webview, WebMessageCompat message, Uri targetOrigin)

Post a message to main frame.

public static voidremoveWebMessageListener(WebView webview, java.lang.String jsObjectName)

Removes the WebMessageListener associated with jsObjectName.

public static voidsetSafeBrowsingAllowlist(java.util.Set<java.lang.String> hosts, <any> callback)

Configures a set of hosts (domain names/IP addresses) that are exempt from SafeBrowsing checks.

public static voidsetSafeBrowsingWhitelist(java.util.List<java.lang.String> hosts, <any> callback)

Sets the list of hosts (domain names/IP addresses) that are exempt from SafeBrowsing checks.

public static voidsetWebViewRenderProcessClient(WebView webview, java.util.concurrent.Executor executor, WebViewRenderProcessClient webViewRenderProcessClient)

Sets the renderer client object associated with this WebView.

public static voidsetWebViewRenderProcessClient(WebView webview, WebViewRenderProcessClient webViewRenderProcessClient)

Sets the renderer client object associated with this WebView.

public static voidstartSafeBrowsing(Context context, <any> callback)

Starts Safe Browsing initialization.

from java.lang.Objectclone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods

public static void postVisualStateCallback(WebView webview, long requestId, WebViewCompat.VisualStateCallback callback)

Posts a WebViewCompat.VisualStateCallback, which will be called when the current state of the WebView is ready to be drawn.

Because updates to the DOM are processed asynchronously, updates to the DOM may not immediately be reflected visually by subsequent invocations. The WebViewCompat.VisualStateCallback provides a mechanism to notify the caller when the contents of the DOM at the current time are ready to be drawn the next time the draws.

The next draw after the callback completes is guaranteed to reflect all the updates to the DOM up to the point at which the WebViewCompat.VisualStateCallback was posted, but it may also contain updates applied after the callback was posted.

The state of the DOM covered by this API includes the following:

  • primitive HTML elements (div, img, span, etc..)
  • images
  • CSS animations
  • WebGL
  • canvas
It does not include the state of:
  • the video tag

To guarantee that the will successfully render the first frame after the WebViewCompat.VisualStateCallback.onComplete(long) method has been called a set of conditions must be met:

  • If the 's visibility is set to VISIBLE then * the must be attached to the view hierarchy.
  • If the 's visibility is set to INVISIBLE then the must be attached to the view hierarchy and must be made VISIBLE from the WebViewCompat.VisualStateCallback.onComplete(long) method.
  • If the 's visibility is set to GONE then the must be attached to the view hierarchy and its 's width and height need to be set to fixed values and must be made VISIBLE from the WebViewCompat.VisualStateCallback.onComplete(long) method.

When using this API it is also recommended to enable pre-rasterization if the is off screen to avoid flickering. See for more details and do consider its caveats.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.VISUAL_STATE_CALLBACK.

Parameters:

requestId: An id that will be returned in the callback to allow callers to match requests with callbacks.
callback: The callback to be invoked.

public static void startSafeBrowsing(Context context, <any> callback)

Starts Safe Browsing initialization.

URL loads are not guaranteed to be protected by Safe Browsing until after callback is invoked with true. Safe Browsing is not fully supported on all devices. For those devices callback will receive false.

This should not be called if Safe Browsing has been disabled by manifest tag or . This prepares resources used for Safe Browsing.

This should be called with the Application Context (and will always use the Application context to do its work regardless).

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.START_SAFE_BROWSING.

Parameters:

context: Application Context.
callback: will be called on the UI thread with true if initialization is successful, false otherwise.

public static void setSafeBrowsingAllowlist(java.util.Set<java.lang.String> hosts, <any> callback)

Configures a set of hosts (domain names/IP addresses) that are exempt from SafeBrowsing checks. The set is global for all the WebViews.

Each rule should take one of these:

Rule Example Matches Subdomain
HOSTNAME example.com Yes
.HOSTNAME .example.com No
IPV4_LITERAL 192.168.1.1 No
IPV6_LITERAL_WITH_BRACKETS [10:20:30:40:50:60:70:80]No

All other rules, including wildcards, are invalid.

The correct syntax for hosts is defined by RFC 3986.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.SAFE_BROWSING_ALLOWLIST.

Parameters:

hosts: the set of hosts for which to skip Safe Browsing checks
callback: will be called with true if hosts are successfully added to the allowlist, false if any hosts are malformed. The callback will be run on the UI thread

public static void setSafeBrowsingWhitelist(java.util.List<java.lang.String> hosts, <any> callback)

Deprecated: Please use WebViewCompat instead.

Sets the list of hosts (domain names/IP addresses) that are exempt from SafeBrowsing checks. The list is global for all the WebViews.

Each rule should take one of these:

Rule Example Matches Subdomain
HOSTNAME example.com Yes
.HOSTNAME .example.com No
IPV4_LITERAL 192.168.1.1 No
IPV6_LITERAL_WITH_BRACKETS [10:20:30:40:50:60:70:80]No

All other rules, including wildcards, are invalid.

The correct syntax for hosts is defined by RFC 3986.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.SAFE_BROWSING_WHITELIST.

Parameters:

hosts: the list of hosts
callback: will be called with true if hosts are successfully added to the allowlist. It will be called with false if any hosts are malformed. The callback will be run on the UI thread

public static Uri getSafeBrowsingPrivacyPolicyUrl()

Returns a URL pointing to the privacy policy for Safe Browsing reporting.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.SAFE_BROWSING_PRIVACY_POLICY_URL.

Returns:

the url pointing to a privacy policy document which can be displayed to users.

public static PackageInfo getCurrentWebViewPackage(Context context)

If WebView has already been loaded into the current process this method will return the package that was used to load it. Otherwise, the package that would be used if the WebView was loaded right now will be returned; this does not cause WebView to be loaded, so this information may become outdated at any time. The WebView package changes either when the current WebView package is updated, disabled, or uninstalled. It can also be changed through a Developer Setting. If the WebView package changes, any app process that has loaded WebView will be killed. The next time the app starts and loads WebView it will use the new WebView package instead.

Returns:

the current WebView package, or null if there is none.

public static WebMessagePortCompat createWebMessageChannel(WebView webview)

Creates a message channel to communicate with JS and returns the message ports that represent the endpoints of this message channel. The HTML5 message channel functionality is described here

The returned message channels are entangled and already in started state.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.CREATE_WEB_MESSAGE_CHANNEL.

Returns:

an array of size two, containing the two message ports that form the message channel.

public static void postWebMessage(WebView webview, WebMessageCompat message, Uri targetOrigin)

Post a message to main frame. The embedded application can restrict the messages to a certain target origin. See HTML5 spec for how target origin can be used.

A target origin can be set as a wildcard ("*"). However this is not recommended. See the page above for security issues.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.POST_WEB_MESSAGE.

Parameters:

message: the WebMessage
targetOrigin: the target origin.

public static void addWebMessageListener(WebView webView, java.lang.String jsObjectName, java.util.Set<java.lang.String> allowedOriginRules, WebViewCompat.WebMessageListener listener)

Adds a WebViewCompat.WebMessageListener to the and injects a JavaScript object into each frame that the WebViewCompat.WebMessageListener will listen on.

The injected JavaScript object will be named jsObjectName in the global scope. This will inject the JavaScript object in any frame whose origin matches allowedOriginRules for every navigation after this call, and the JavaScript object will be available immediately when the page begins to load.

Each allowedOriginRules entry must follow the format SCHEME "://" [ HOSTNAME_PATTERN [ ":" PORT ] ], each part is explained in the below table:

RuleDescriptionExample
http/https with hostname SCHEME is http or https; HOSTNAME_PATTERN is a regular hostname; PORT is optional, when not present, the rule will match port 80 for http and port 443 for https.
  • https://foobar.com:8080 - Matches https:// URL on port 8080, whose normalized host is foobar.com.
  • https://www.example.com - Matches https:// URL on port 443, whose normalized host is www.example.com.
http/https with pattern matching SCHEME is http or https; HOSTNAME_PATTERN is a sub-domain matching pattern with a leading *.; PORT is optional, when not present, the rule will match port 80 for http and port 443 for https.
  • https://*.example.com - Matches https://calendar.example.com and https://foo.bar.example.com but not https://example.com.
  • https://*.example.com:8080 - Matches https://calendar.example.com:8080
http/https with IP literal SCHEME is https or https; HOSTNAME_PATTERN is IP literal; PORT is optional, when not present, the rule will match port 80 for http and port 443 for https.
  • https://127.0.0.1 - Matches https:// URL on port 443, whose IPv4 address is 127.0.0.1
  • https://[::1] or https://[0:0::1]- Matches any URL to the IPv6 loopback address with port 443.
  • https://[::1]:99 - Matches any https:// URL to the IPv6 loopback on port 99.
Custom scheme SCHEME is a custom scheme; HOSTNAME_PATTERN and PORT must not be present.
  • my-app-scheme:// - Matches any my-app-scheme:// URL.
* Wildcard rule, matches any origin.
  • *

Note that this is a powerful API, as the JavaScript object will be injected when the frame's origin matches any one of the allowed origins. The HTTPS scheme is strongly recommended for security; allowing HTTP origins exposes the injected object to any potential network-based attackers. If a wildcard "*" is provided, it will inject the JavaScript object to all frames. A wildcard should only be used if the app wants any third party web page to be able to use the injected object. When using a wildcard, the app must treat received messages as untrustworthy and validate any data carefully.

This method can be called multiple times to inject multiple JavaScript objects.

Let's say the injected JavaScript object is named myObject. We will have following methods on that object once it is available to use:

 // Web page (in JavaScript)
 // message needs to be a JavaScript String, MessagePorts is an optional parameter.
 myObject.postMessage(message[, MessagePorts])

 // To receive messages posted from the app side, assign a function to the "onmessage"
 // property. This function should accept a single "event" argument. "event" has a "data"
 // property, which is the message string from the app side.
 myObject.onmessage = function(event) { ... }

 // To be compatible with DOM EventTarget's addEventListener, it accepts type and listener
 // parameters, where type can be only "message" type and listener can only be a JavaScript
 // function for myObject. An event object will be passed to listener with a "data" property,
 // which is the message string from the app side.
 myObject.addEventListener(type, listener)

 // To be compatible with DOM EventTarget's removeEventListener, it accepts type and listener
 // parameters, where type can be only "message" type and listener can only be a JavaScript
 // function for myObject.
 myObject.removeEventListener(type, listener)
 

We start the communication between JavaScript and the app from the JavaScript side. In order to send message from the app to JavaScript, it needs to post a message from JavaScript first, so the app will have a JavaScriptReplyProxy object to respond. Example:

 // Web page (in JavaScript)
 myObject.onmessage = function(event) {
   // prints "Got it!" when we receive the app's response.
   console.log(event.data);
 }
 myObject.postMessage("I'm ready!");
 
 // App (in Java)
 WebMessageListener myListener = new WebMessageListener() {
   @Override
   public void onPostMessage(WebView view, WebMessageCompat message, Uri sourceOrigin,
            boolean isMainFrame, JavaScriptReplyProxy replyProxy) {
     // do something about view, message, sourceOrigin and isMainFrame.
     replyProxy.postMessage("Got it!");
   }
 };
 if (WebViewFeature.isFeatureSupported(WebViewFeature.WEB_MESSAGE_LISTENER)) {
   WebViewCompat.addWebMessageListener(webView, "myObject", rules, myListener);
 }
 

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.WEB_MESSAGE_LISTENER.

Parameters:

webView: The instance that we are interacting with.
jsObjectName: The name for the injected JavaScript object for this WebViewCompat.WebMessageListener.
allowedOriginRules: A set of matching rules for the allowed origins.
listener: The WebMessageListener to handle postMessage() calls on the JavaScript object.

See also: JavaScriptReplyProxy, WebViewCompat.WebMessageListener

public static void removeWebMessageListener(WebView webview, java.lang.String jsObjectName)

Removes the WebMessageListener associated with jsObjectName.

Note that after this call, the injected JavaScript object is still in the JavaScript context, however any message sent after this call won't reach the WebMessageListener.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.WEB_MESSAGE_LISTENER.

Parameters:

jsObjectName: The JavaScript object's name that was previously passed to WebViewCompat.addWebMessageListener(WebView, String, Set, WebViewCompat.WebMessageListener).

See also: WebViewCompat.addWebMessageListener(WebView, String, Set, WebViewCompat.WebMessageListener)

public static ScriptHandler addDocumentStartJavaScript(WebView webview, java.lang.String script, java.util.Set<java.lang.String> allowedOriginRules)

Adds a JavaScript script to the which will be executed in any frame whose origin matches allowedOriginRules when the document begins to load.

Note that the script will run before any of the page's JavaScript code and the DOM tree might not be ready at this moment. It will block the loadng of the page until it's finished, so should be kept as short as possible.

The injected object from WebViewCompat.addWebMessageListener(WebView, String, Set, WebViewCompat.WebMessageListener) API will be injected first and the script can rely on the injected object to send messages to the app.

The script will only run in frames which begin loading after the call returns, therefore it should typically be called before making any loadUrl(), loadData() or loadDataWithBaseURL() call to load the page.

This method can be called multiple times to inject multiple scripts. If more than one script matches a frame's origin, they will be executed in the order they were added.

See WebViewCompat.addWebMessageListener(WebView, String, Set, WebViewCompat.WebMessageListener) for the rules of the allowedOriginRules parameter.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.DOCUMENT_START_SCRIPT.

Parameters:

webview: The instance that we are interacting with.
script: The JavaScript script to be executed.
allowedOriginRules: A set of matching rules for the allowed origins.

Returns:

the ScriptHandler, which is a handle for removing the script.

See also: WebViewCompat.addWebMessageListener(WebView, String, Set, WebViewCompat.WebMessageListener), TODO(swestphal): unhide when ready.

public static WebViewClient getWebViewClient(WebView webview)

Gets the WebViewClient for the WebView argument.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.GET_WEB_VIEW_CLIENT.

Returns:

the WebViewClient, or a default client if not yet set

public static WebChromeClient getWebChromeClient(WebView webview)

Gets the WebChromeClient.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.GET_WEB_CHROME_CLIENT.

Returns:

the WebChromeClient, or null if not yet set

public static WebViewRenderProcess getWebViewRenderProcess(WebView webview)

Gets the WebView renderer associated with this WebView.

In Android O and above, WebView may run in "multiprocess" mode. In multiprocess mode, rendering of web content is performed by a sandboxed renderer process separate to the application process. This renderer process may be shared with other WebViews in the application, but is not shared with other application processes.

If WebView is running in multiprocess mode, this method returns a handle to the renderer process associated with the WebView, which can be used to control the renderer process.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.GET_WEB_VIEW_RENDERER.

Returns:

the WebViewRenderProcess renderer handle associated with this , or null if WebView is not running in multiprocess mode.

public static void setWebViewRenderProcessClient(WebView webview, java.util.concurrent.Executor executor, WebViewRenderProcessClient webViewRenderProcessClient)

Sets the renderer client object associated with this WebView.

The renderer client encapsulates callbacks relevant to WebView renderer state. See WebViewRenderProcessClient for details.

Although many WebView instances may share a single underlying renderer, and renderers may live either in the application process, or in a sandboxed process that is isolated from the application process, instances of WebViewRenderProcessClient are set per-WebView. Callbacks represent renderer events from the perspective of this WebView, and may or may not be correlated with renderer events affecting other WebViews.

The renderer client encapsulates callbacks relevant to WebView renderer state. See WebViewRenderProcessClient for details.

Although many WebView instances may share a single underlying renderer, and renderers may live either in the application process, or in a sandboxed process that is isolated from the application process, instances of WebViewRenderProcessClient are set per-WebView. Callbacks represent renderer events from the perspective of this WebView, and may or may not be correlated with renderer events affecting other WebViews.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE.

Parameters:

webview: the on which to monitor responsiveness.
executor: the java.util.concurrent.Executor that will be used to execute callbacks.
webViewRenderProcessClient: the WebViewRenderProcessClient to set for callbacks.

public static void setWebViewRenderProcessClient(WebView webview, WebViewRenderProcessClient webViewRenderProcessClient)

Sets the renderer client object associated with this WebView.

See WebViewCompat.setWebViewRenderProcessClient(WebView, Executor, WebViewRenderProcessClient) for details, with the following differences:

Callbacks will execute directly on the thread on which this WebView was instantiated.

Passing null for webViewRenderProcessClient will clear the renderer client object for this WebView.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE.

Parameters:

webview: the on which to monitor responsiveness.
webViewRenderProcessClient: the WebViewRenderProcessClient to set for callbacks.

public static WebViewRenderProcessClient getWebViewRenderProcessClient(WebView webview)

Gets the renderer client object associated with this WebView.

This method should only be called if WebViewFeature.isFeatureSupported(String) returns true for WebViewFeature.WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE.

Returns:

the WebViewRenderProcessClient object associated with this WebView, if one has been set via WebViewCompat.setWebViewRenderProcessClient(WebView, WebViewRenderProcessClient) or null otherwise.

public static boolean isMultiProcessEnabled()

Returns true if is running in multi process mode.

In Android O and above, WebView may run in "multiprocess" mode. In multiprocess mode, rendering of web content is performed by a sandboxed renderer process separate to the application process. This renderer process may be shared with other WebViews in the application, but is not shared with other application processes.

public static java.lang.String getVariationsHeader()

Gets the WebView variations encoded to be used as the X-Client-Data HTTP header.

The app is responsible for adding the X-Client-Data header to any request that may use variations metadata, such as requests to Google web properties. The returned string will be a base64 encoded ClientVariations proto: https://source.chromium.org/chromium/chromium/src/+/main:components/variations/proto/client_variations.proto

Returns:

the variations header. The string may be empty if the header is not available.

See also:

Source

/*
 * Copyright 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.webkit;

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.os.Build;
import android.os.Looper;
import android.webkit.ValueCallback;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.RequiresFeature;
import androidx.annotation.RestrictTo;
import androidx.annotation.UiThread;
import androidx.webkit.internal.ApiFeature;
import androidx.webkit.internal.ApiHelperForM;
import androidx.webkit.internal.ApiHelperForO;
import androidx.webkit.internal.ApiHelperForOMR1;
import androidx.webkit.internal.ApiHelperForP;
import androidx.webkit.internal.ApiHelperForQ;
import androidx.webkit.internal.WebMessagePortImpl;
import androidx.webkit.internal.WebViewFeatureInternal;
import androidx.webkit.internal.WebViewGlueCommunicator;
import androidx.webkit.internal.WebViewProviderAdapter;
import androidx.webkit.internal.WebViewProviderFactory;
import androidx.webkit.internal.WebViewRenderProcessClientFrameworkAdapter;
import androidx.webkit.internal.WebViewRenderProcessImpl;

import org.chromium.support_lib_boundary.WebViewProviderBoundaryInterface;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.concurrent.Executor;

/**
 * Compatibility version of {@link android.webkit.WebView}
 */
public class WebViewCompat {
    private static final Uri WILDCARD_URI = Uri.parse("*");
    private static final Uri EMPTY_URI = Uri.parse("");

    private WebViewCompat() {} // Don't allow instances of this class to be constructed.

    /**
     * Callback interface supplied to {@link #postVisualStateCallback} for receiving
     * notifications about the visual state.
     */
    public interface VisualStateCallback {
        /**
         * Invoked when the visual state is ready to be drawn in the next {@link WebView#onDraw}.
         *
         * @param requestId The identifier passed to {@link #postVisualStateCallback} when this
         *                  callback was posted.
         */
        @UiThread
        void onComplete(long requestId);
    }

    /**
     * This listener receives messages sent on the JavaScript object which was injected by {@link
     * #addWebMessageListener(WebView, String, Set, WebViewCompat.WebMessageListener)}.
     */
    public interface WebMessageListener {
        /**
         * Receives a message sent by a {@code postMessage()} on the injected JavaScript object.
         *
         * <p> Note that when the frame is {@code file:} or {@code content:} origin, the value of
         * {@code sourceOrigin} is a string {@code "null"}. However we highly recommend to not use
         * {@code file:} or {@code content:} URLs, see {@link WebViewAssetLoader} for serving local
         * content under {@code http:} or {@code https:} domain.
         *
         * @param view The {@link WebView} containing the frame which sent this message.
         * @param message The message from JavaScript.
         * @param sourceOrigin The origin of the frame that the message is from.
         * @param isMainFrame {@code true} If the message is from the main frame.
         * @param replyProxy Used to reply back to the JavaScript object.
         */
        @UiThread
        void onPostMessage(@NonNull WebView view, @NonNull WebMessageCompat message,
                @NonNull Uri sourceOrigin, boolean isMainFrame,
                @NonNull JavaScriptReplyProxy replyProxy);
    }

    /**
     * Posts a {@link VisualStateCallback}, which will be called when
     * the current state of the WebView is ready to be drawn.
     *
     * <p>Because updates to the DOM are processed asynchronously, updates to the DOM may not
     * immediately be reflected visually by subsequent {@link WebView#onDraw} invocations. The
     * {@link VisualStateCallback} provides a mechanism to notify the caller when the contents
     * of the DOM at the current time are ready to be drawn the next time the {@link WebView} draws.
     *
     * <p>The next draw after the callback completes is guaranteed to reflect all the updates to the
     * DOM up to the point at which the {@link VisualStateCallback} was posted, but it may
     * also contain updates applied after the callback was posted.
     *
     * <p>The state of the DOM covered by this API includes the following:
     * <ul>
     * <li>primitive HTML elements (div, img, span, etc..)</li>
     * <li>images</li>
     * <li>CSS animations</li>
     * <li>WebGL</li>
     * <li>canvas</li>
     * </ul>
     * It does not include the state of:
     * <ul>
     * <li>the video tag</li>
     * </ul>
     *
     * <p>To guarantee that the {@link WebView} will successfully render the first frame
     * after the {@link VisualStateCallback#onComplete} method has been called a set of
     * conditions must be met:
     * <ul>
     * <li>If the {@link WebView}'s visibility is set to {@link android.view.View#VISIBLE VISIBLE}
     * then * the {@link WebView} must be attached to the view hierarchy.</li>
     * <li>If the {@link WebView}'s visibility is set to
     * {@link android.view.View#INVISIBLE INVISIBLE} then the {@link WebView} must be attached to
     * the view hierarchy and must be made {@link android.view.View#VISIBLE VISIBLE} from the
     * {@link VisualStateCallback#onComplete} method.</li>
     * <li>If the {@link WebView}'s visibility is set to {@link android.view.View#GONE GONE} then
     * the {@link WebView} must be attached to the view hierarchy and its
     * {@link android.widget.AbsoluteLayout.LayoutParams LayoutParams}'s width and height need to be
     * set to fixed values and must be made {@link android.view.View#VISIBLE VISIBLE} from the
     * {@link VisualStateCallback#onComplete} method.</li>
     * </ul>
     *
     * <p>When using this API it is also recommended to enable pre-rasterization if the {@link
     * WebView} is off screen to avoid flickering. See
     * {@link android.webkit.WebSettings#setOffscreenPreRaster} for more details and do consider its
     * caveats.
     *
     * <p>
     * This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#VISUAL_STATE_CALLBACK}.
     *
     * @param requestId An id that will be returned in the callback to allow callers to match
     *                  requests with callbacks.
     * @param callback  The callback to be invoked.
     */
    @RequiresFeature(name = WebViewFeature.VISUAL_STATE_CALLBACK,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static void postVisualStateCallback(@NonNull WebView webview, long requestId,
            @NonNull final VisualStateCallback callback) {
        ApiFeature.M feature = WebViewFeatureInternal.VISUAL_STATE_CALLBACK;
        if (feature.isSupportedByFramework()) {
            ApiHelperForM.postVisualStateCallback(webview, requestId, callback);
        } else if (feature.isSupportedByWebView()) {
            checkThread(webview);
            getProvider(webview).insertVisualStateCallback(requestId, callback);
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Starts Safe Browsing initialization.
     * <p>
     * URL loads are not guaranteed to be protected by Safe Browsing until after {@code callback} is
     * invoked with {@code true}. Safe Browsing is not fully supported on all devices. For those
     * devices {@code callback} will receive {@code false}.
     * <p>
     * This should not be called if Safe Browsing has been disabled by manifest tag or {@link
     * android.webkit.WebSettings#setSafeBrowsingEnabled}. This prepares resources used for Safe
     * Browsing.
     * <p>
     * This should be called with the Application Context (and will always use the Application
     * context to do its work regardless).
     *
     * <p>
     * This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#START_SAFE_BROWSING}.
     *
     * @param context Application Context.
     * @param callback will be called on the UI thread with {@code true} if initialization is
     * successful, {@code false} otherwise.
     */
    @RequiresFeature(name = WebViewFeature.START_SAFE_BROWSING,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static void startSafeBrowsing(@NonNull Context context,
            @Nullable ValueCallback<Boolean> callback) {
        ApiFeature.O_MR1 feature = WebViewFeatureInternal.START_SAFE_BROWSING;
        if (feature.isSupportedByFramework()) {
            ApiHelperForOMR1.startSafeBrowsing(context, callback);
        } else if (feature.isSupportedByWebView()) {
            getFactory().getStatics().initSafeBrowsing(context, callback);
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Configures a set of hosts (domain names/IP addresses) that are exempt from SafeBrowsing
     * checks. The set is global for all the WebViews.
     * <p>
     * Each rule should take one of these:
     * <table>
     * <tr><th> Rule </th> <th> Example </th> <th> Matches Subdomain</th> </tr>
     * <tr><td> HOSTNAME </td> <td> example.com </td> <td> Yes </td> </tr>
     * <tr><td> .HOSTNAME </td> <td> .example.com </td> <td> No </td> </tr>
     * <tr><td> IPV4_LITERAL </td> <td> 192.168.1.1 </td> <td> No </td></tr>
     * <tr><td> IPV6_LITERAL_WITH_BRACKETS </td><td>[10:20:30:40:50:60:70:80]</td><td>No</td></tr>
     * </table>
     * <p>
     * All other rules, including wildcards, are invalid.
     * <p>
     * The correct syntax for hosts is defined by <a
     * href="https://tools.ietf.org/html/rfc3986#section-3.2.2">RFC 3986</a>.
     *
     * <p>
     * This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#SAFE_BROWSING_ALLOWLIST}.
     *
     * @param hosts the set of hosts for which to skip Safe Browsing checks
     * @param callback will be called with {@code true} if hosts are successfully added to the
     * allowlist, {@code false} if any hosts are malformed. The callback will be run on the UI
     * thread
     */
    @RequiresFeature(name = WebViewFeature.SAFE_BROWSING_ALLOWLIST,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static void setSafeBrowsingAllowlist(@NonNull Set<String> hosts,
            @Nullable ValueCallback<Boolean> callback) {
        ApiFeature.O_MR1 preferredFeature =
                WebViewFeatureInternal.SAFE_BROWSING_ALLOWLIST_PREFERRED_TO_PREFERRED;
        ApiFeature.O_MR1 deprecatedFeature =
                WebViewFeatureInternal.SAFE_BROWSING_ALLOWLIST_PREFERRED_TO_DEPRECATED;
        if (preferredFeature.isSupportedByWebView()) {
            getFactory().getStatics().setSafeBrowsingAllowlist(hosts, callback);
            return;
        }
        List<String> hostsList = new ArrayList<>(hosts);
        if (deprecatedFeature.isSupportedByFramework()) {
            ApiHelperForOMR1.setSafeBrowsingWhitelist(hostsList, callback);
        } else if (deprecatedFeature.isSupportedByWebView()) {
            getFactory().getStatics().setSafeBrowsingWhitelist(hostsList, callback);
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Sets the list of hosts (domain names/IP addresses) that are exempt from SafeBrowsing checks.
     * The list is global for all the WebViews.
     * <p>
     * Each rule should take one of these:
     * <table>
     * <tr><th> Rule </th> <th> Example </th> <th> Matches Subdomain</th> </tr>
     * <tr><td> HOSTNAME </td> <td> example.com </td> <td> Yes </td> </tr>
     * <tr><td> .HOSTNAME </td> <td> .example.com </td> <td> No </td> </tr>
     * <tr><td> IPV4_LITERAL </td> <td> 192.168.1.1 </td> <td> No </td></tr>
     * <tr><td> IPV6_LITERAL_WITH_BRACKETS </td><td>[10:20:30:40:50:60:70:80]</td><td>No</td></tr>
     * </table>
     * <p>
     * All other rules, including wildcards, are invalid.
     * <p>
     * The correct syntax for hosts is defined by <a
     * href="https://tools.ietf.org/html/rfc3986#section-3.2.2">RFC 3986</a>.
     *
     * <p>
     * This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#SAFE_BROWSING_WHITELIST}.
     *
     * @param hosts the list of hosts
     * @param callback will be called with {@code true} if hosts are successfully added to the
     * allowlist. It will be called with {@code false} if any hosts are malformed. The callback
     * will be run on the UI thread
     *
     * @deprecated Please use {@link #setSafeBrowsingAllowlist(Set, ValueCallback)} instead.
     */
    @Deprecated
    @RequiresFeature(name = WebViewFeature.SAFE_BROWSING_WHITELIST,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static void setSafeBrowsingWhitelist(@NonNull List<String> hosts,
            @Nullable ValueCallback<Boolean> callback) {
        setSafeBrowsingAllowlist(new HashSet<>(hosts), callback);
    }

    /**
     * Returns a URL pointing to the privacy policy for Safe Browsing reporting.
     *
     * <p>
     * This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#SAFE_BROWSING_PRIVACY_POLICY_URL}.
     *
     * @return the url pointing to a privacy policy document which can be displayed to users.
     */
    @NonNull
    @RequiresFeature(name = WebViewFeature.SAFE_BROWSING_PRIVACY_POLICY_URL,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static Uri getSafeBrowsingPrivacyPolicyUrl() {
        ApiFeature.O_MR1 feature =
                WebViewFeatureInternal.SAFE_BROWSING_PRIVACY_POLICY_URL;
        if (feature.isSupportedByFramework()) {
            return ApiHelperForOMR1.getSafeBrowsingPrivacyPolicyUrl();
        } else if (feature.isSupportedByWebView()) {
            return getFactory().getStatics().getSafeBrowsingPrivacyPolicyUrl();
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * If WebView has already been loaded into the current process this method will return the
     * package that was used to load it. Otherwise, the package that would be used if the WebView
     * was loaded right now will be returned; this does not cause WebView to be loaded, so this
     * information may become outdated at any time.
     * The WebView package changes either when the current WebView package is updated, disabled, or
     * uninstalled. It can also be changed through a Developer Setting.
     * If the WebView package changes, any app process that has loaded WebView will be killed. The
     * next time the app starts and loads WebView it will use the new WebView package instead.
     * @return the current WebView package, or {@code null} if there is none.
     */
    // Note that this API is not protected by a {@link androidx.webkit.WebViewFeature} since
    // this feature is not dependent on the WebView APK.
    @Nullable
    public static PackageInfo getCurrentWebViewPackage(@NonNull Context context) {
        // There was no WebView Package before Lollipop, the WebView code was part of the framework
        // back then.
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
            return null;
        }

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            return ApiHelperForO.getCurrentWebViewPackage();
        } else { // L-N
            try {
                PackageInfo loadedWebViewPackageInfo = getLoadedWebViewPackageInfo();
                if (loadedWebViewPackageInfo != null) return loadedWebViewPackageInfo;
            } catch (ClassNotFoundException | IllegalAccessException | InvocationTargetException
                | NoSuchMethodException  e) {
                return null;
            }

            // If WebViewFactory.getLoadedPackageInfo() returns null then WebView hasn't been loaded
            // yet, in that case we need to fetch the name of the WebView package, and fetch the
            // corresponding PackageInfo through the PackageManager
            return getNotYetLoadedWebViewPackageInfo(context);
        }
    }

    /**
     * Return the PackageInfo of the currently loaded WebView APK. This method uses reflection and
     * propagates any exceptions thrown, to the caller.
     */
    @SuppressLint("PrivateApi")
    private static PackageInfo getLoadedWebViewPackageInfo()
            throws ClassNotFoundException, NoSuchMethodException, InvocationTargetException,
            IllegalAccessException {
        Class<?> webViewFactoryClass = Class.forName("android.webkit.WebViewFactory");
        return (PackageInfo) webViewFactoryClass.getMethod(
                "getLoadedPackageInfo").invoke(null);
    }

    /**
     * Return the PackageInfo of the WebView APK that would have been used as WebView implementation
     * if WebView was to be loaded right now.
     */
    @SuppressLint("PrivateApi")
    @SuppressWarnings("deprecation")
    private static PackageInfo getNotYetLoadedWebViewPackageInfo(Context context) {
        String webviewPackageName;
        try {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP
                    && Build.VERSION.SDK_INT <= Build.VERSION_CODES.M) {
                Class<?> webViewFactoryClass = Class.forName("android.webkit.WebViewFactory");

                webviewPackageName = (String) webViewFactoryClass.getMethod(
                        "getWebViewPackageName").invoke(null);
            } else {
                Class<?> webviewUpdateServiceClass =
                        Class.forName("android.webkit.WebViewUpdateService");
                webviewPackageName = (String) webviewUpdateServiceClass.getMethod(
                        "getCurrentWebViewPackageName").invoke(null);
            }
        } catch (ClassNotFoundException e) {
            return null;
        } catch (IllegalAccessException e) {
            return null;
        } catch (InvocationTargetException e) {
            return null;
        } catch (NoSuchMethodException e) {
            return null;
        }
        if (webviewPackageName == null) return null;
        PackageManager pm = context.getPackageManager();
        try {
            return pm.getPackageInfo(webviewPackageName, 0);
        } catch (PackageManager.NameNotFoundException e) {
            return null;
        }
    }

    private static WebViewProviderAdapter getProvider(WebView webview) {
        return new WebViewProviderAdapter(createProvider(webview));
    }

    /**
     * Creates a message channel to communicate with JS and returns the message
     * ports that represent the endpoints of this message channel. The HTML5 message
     * channel functionality is described
     * <a href="https://html.spec.whatwg.org/multipage/comms.html#messagechannel">here
     * </a>
     *
     * <p>The returned message channels are entangled and already in started state.
     *
     * <p>
     * This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#CREATE_WEB_MESSAGE_CHANNEL}.
     *
     * @return an array of size two, containing the two message ports that form the message channel.
     */
    @RequiresFeature(name = WebViewFeature.CREATE_WEB_MESSAGE_CHANNEL,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static @NonNull WebMessagePortCompat[] createWebMessageChannel(
            @NonNull WebView webview) {
        final ApiFeature.M feature = WebViewFeatureInternal.CREATE_WEB_MESSAGE_CHANNEL;
        if (feature.isSupportedByFramework()) {
            return WebMessagePortImpl.portsToCompat(ApiHelperForM.createWebMessageChannel(webview));
        } else if (feature.isSupportedByWebView()) {
            return getProvider(webview).createWebMessageChannel();
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Post a message to main frame. The embedded application can restrict the
     * messages to a certain target origin. See
     * <a href="https://html.spec.whatwg.org/multipage/comms.html#posting-messages">
     * HTML5 spec</a> for how target origin can be used.
     * <p>
     * A target origin can be set as a wildcard ("*"). However this is not recommended.
     * See the page above for security issues.
     *
     * <p>
     * This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#POST_WEB_MESSAGE}.
     *
     * @param message the WebMessage
     * @param targetOrigin the target origin.
     */
    @RequiresFeature(name = WebViewFeature.POST_WEB_MESSAGE,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static void postWebMessage(@NonNull WebView webview, @NonNull WebMessageCompat message,
            @NonNull Uri targetOrigin) {
        // The wildcard ("*") Uri was first supported in WebView 60, see
        // crrev/5ec5b67cbab33cea51b0ee11a286c885c2de4d5d, so on some Android versions using "*"
        // won't work. WebView has always supported using an empty Uri "" as a wildcard - so convert
        // "*" into "" here.
        if (WILDCARD_URI.equals(targetOrigin)) {
            targetOrigin = EMPTY_URI;
        }

        final ApiFeature.M feature = WebViewFeatureInternal.POST_WEB_MESSAGE;
        if (feature.isSupportedByFramework()) {
            ApiHelperForM.postWebMessage(webview,
                    WebMessagePortImpl.compatToFrameworkMessage(message), targetOrigin);
        } else if (feature.isSupportedByWebView()) {
            getProvider(webview).postWebMessage(message, targetOrigin);
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Adds a {@link WebMessageListener} to the {@link WebView} and injects a JavaScript object into
     * each frame that the {@link WebMessageListener} will listen on.
     *
     * <p>
     * The injected JavaScript object will be named {@code jsObjectName} in the global scope. This
     * will inject the JavaScript object in any frame whose origin matches {@code
     * allowedOriginRules} for every navigation after this call, and the JavaScript object will be
     * available immediately when the page begins to load.
     *
     * <p>
     * Each {@code allowedOriginRules} entry must follow the format {@code SCHEME "://" [
     * HOSTNAME_PATTERN [ ":" PORT ] ]}, each part is explained in the below table:
     *
     * <table>
     * <tr><th>Rule</th><th>Description</th><th>Example</th></tr>
     *
     * <tr>
     * <td>http/https with hostname</td>
     * <td>{@code SCHEME} is http or https; {@code HOSTNAME_PATTERN} is a regular hostname; {@code
     * PORT} is optional, when not present, the rule will match port {@code 80} for http and port
     * {@code 443} for https.</td>
     * <td><ul>
     * <li>{@code https://foobar.com:8080} - Matches https:// URL on port 8080, whose normalized
     * host is foobar.com.</li>
     * <li>{@code https://www.example.com} - Matches https:// URL on port 443, whose normalized host
     * is www.example.com.</li>
     * </ul></td>
     * </tr>
     *
     * <tr>
     * <td>http/https with pattern matching</td>
     * <td>{@code SCHEME} is http or https; {@code HOSTNAME_PATTERN} is a sub-domain matching
     * pattern with a leading {@code *.}; {@code PORT} is optional, when not present, the rule will
     * match port {@code 80} for http and port {@code 443} for https.</td>
     *
     * <td><ul>
     * <li>{@code https://*.example.com} - Matches https://calendar.example.com and
     * https://foo.bar.example.com but not https://example.com.</li>
     * <li>{@code https://*.example.com:8080} - Matches https://calendar.example.com:8080</li>
     * </ul></td>
     * </tr>
     *
     * <tr>
     * <td>http/https with IP literal</td>
     * <td>{@code SCHEME} is https or https; {@code HOSTNAME_PATTERN} is IP literal; {@code PORT} is
     * optional, when not present, the rule will match port {@code 80} for http and port {@code 443}
     * for https.</td>
     *
     * <td><ul>
     * <li>{@code https://127.0.0.1} - Matches https:// URL on port 443, whose IPv4 address is
     * 127.0.0.1</li>
     * <li>{@code https://[::1]} or {@code https://[0:0::1]}- Matches any URL to the IPv6 loopback
     * address with port 443.</li>
     * <li>{@code https://[::1]:99} - Matches any https:// URL to the IPv6 loopback on port 99.</li>
     * </ul></td>
     * </tr>
     *
     * <tr>
     * <td>Custom scheme</td>
     * <td>{@code SCHEME} is a custom scheme; {@code HOSTNAME_PATTERN} and {@code PORT} must not be
     * present.</td>
     * <td><ul>
     * <li>{@code my-app-scheme://} - Matches any my-app-scheme:// URL.</li>
     * </ul></td>
     * </tr>
     *
     * <tr><td>{@code *}</td>
     * <td>Wildcard rule, matches any origin.</td>
     * <td><ul><li>{@code *}</li></ul></td>
     * </table>
     *
     * <p>
     * Note that this is a powerful API, as the JavaScript object will be injected when the frame's
     * origin matches any one of the allowed origins. The HTTPS scheme is strongly recommended for
     * security; allowing HTTP origins exposes the injected object to any potential network-based
     * attackers. If a wildcard {@code "*"} is provided, it will inject the JavaScript object to all
     * frames. A wildcard should only be used if the app wants <b>any</b> third party web page to be
     * able to use the injected object. When using a wildcard, the app must treat received messages
     * as untrustworthy and validate any data carefully.
     *
     * <p>
     * This method can be called multiple times to inject multiple JavaScript objects.
     *
     * <p>
     * Let's say the injected JavaScript object is named {@code myObject}. We will have following
     * methods on that object once it is available to use:
     * <pre class="prettyprint">
     * // Web page (in JavaScript)
     * // message needs to be a JavaScript String, MessagePorts is an optional parameter.
     * myObject.postMessage(message[, MessagePorts])
     *
     * // To receive messages posted from the app side, assign a function to the "onmessage"
     * // property. This function should accept a single "event" argument. "event" has a "data"
     * // property, which is the message string from the app side.
     * myObject.onmessage = function(event) { ... }
     *
     * // To be compatible with DOM EventTarget's addEventListener, it accepts type and listener
     * // parameters, where type can be only "message" type and listener can only be a JavaScript
     * // function for myObject. An event object will be passed to listener with a "data" property,
     * // which is the message string from the app side.
     * myObject.addEventListener(type, listener)
     *
     * // To be compatible with DOM EventTarget's removeEventListener, it accepts type and listener
     * // parameters, where type can be only "message" type and listener can only be a JavaScript
     * // function for myObject.
     * myObject.removeEventListener(type, listener)
     * </pre>
     *
     * <p>
     * We start the communication between JavaScript and the app from the JavaScript side. In order
     * to send message from the app to JavaScript, it needs to post a message from JavaScript first,
     * so the app will have a {@link JavaScriptReplyProxy} object to respond. Example:
     * <pre class="prettyprint">
     * // Web page (in JavaScript)
     * myObject.onmessage = function(event) {
     *   // prints "Got it!" when we receive the app's response.
     *   console.log(event.data);
     * }
     * myObject.postMessage("I'm ready!");
     * </pre>
     * <pre class="prettyprint">
     * // App (in Java)
     * WebMessageListener myListener = new WebMessageListener() {
     *   &#064;Override
     *   public void onPostMessage(WebView view, WebMessageCompat message, Uri sourceOrigin,
     *            boolean isMainFrame, JavaScriptReplyProxy replyProxy) {
     *     // do something about view, message, sourceOrigin and isMainFrame.
     *     replyProxy.postMessage("Got it!");
     *   }
     * };
     * if (WebViewFeature.isFeatureSupported(WebViewFeature.WEB_MESSAGE_LISTENER)) {
     *   WebViewCompat.addWebMessageListener(webView, "myObject", rules, myListener);
     * }
     * </pre>
     *
     * <p>
     * This method should only be called if {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#WEB_MESSAGE_LISTENER}.
     *
     * @param webView The {@link WebView} instance that we are interacting with.
     * @param jsObjectName The name for the injected JavaScript object for this {@link
     *         WebMessageListener}.
     * @param allowedOriginRules A set of matching rules for the allowed origins.
     * @param listener The {@link WebMessageListener WebMessageListener} to handle postMessage()
     *         calls on the JavaScript object.
     * @throws IllegalArgumentException If one of the {@code allowedOriginRules} is invalid.
     *
     * @see JavaScriptReplyProxy
     * @see WebMessageListener
     */
    @RequiresFeature(name = WebViewFeature.WEB_MESSAGE_LISTENER,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static void addWebMessageListener(@NonNull WebView webView, @NonNull String jsObjectName,
            @NonNull Set<String> allowedOriginRules, @NonNull WebMessageListener listener) {
        final ApiFeature.NoFramework feature = WebViewFeatureInternal.WEB_MESSAGE_LISTENER;
        if (feature.isSupportedByWebView()) {
            getProvider(webView).addWebMessageListener(
                    jsObjectName, allowedOriginRules.toArray(new String[0]), listener);
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Removes the {@link WebMessageListener WebMessageListener} associated with {@code
     * jsObjectName}.
     *
     * <p>
     * Note that after this call, the injected JavaScript object is still in the JavaScript context,
     * however any message sent after this call won't reach the {@link WebMessageListener
     * WebMessageListener}.
     *
     * <p>
     * This method should only be called if {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#WEB_MESSAGE_LISTENER}.
     *
     * @param jsObjectName The JavaScript object's name that was previously passed to {@link
     *         #addWebMessageListener(WebView, String, Set, WebMessageListener)}.
     *
     * @see #addWebMessageListener(WebView, String, Set, WebMessageListener)
     */
    @RequiresFeature(name = WebViewFeature.WEB_MESSAGE_LISTENER,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static void removeWebMessageListener(
            @NonNull WebView webview, @NonNull String jsObjectName) {
        final ApiFeature.NoFramework feature = WebViewFeatureInternal.WEB_MESSAGE_LISTENER;
        if (feature.isSupportedByWebView()) {
            getProvider(webview).removeWebMessageListener(jsObjectName);
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Adds a JavaScript script to the {@link WebView} which will be executed in any frame whose
     * origin matches {@code allowedOriginRules} when the document begins to load.
     *
     * <p>Note that the script will run before any of the page's JavaScript code and the DOM tree
     * might not be ready at this moment. It will block the loadng of the page until it's finished,
     * so should be kept as short as possible.
     *
     * <p>The injected object from {@link #addWebMessageListener(WebView, String, Set,
     * WebMessageListener)} API will be injected first and the script can rely on the injected
     * object to send messages to the app.
     *
     * <p>The script will only run in frames which begin loading after the call returns, therefore
     * it should typically be called before making any {@code loadUrl()}, {@code loadData()} or
     * {@code loadDataWithBaseURL()} call to load the page.
     *
     * <p>This method can be called multiple times to inject multiple scripts. If more than one
     * script matches a frame's origin, they will be executed in the order they were added.
     *
     * <p>See {@link #addWebMessageListener(WebView, String, Set, WebMessageListener)} for the rules
     * of the {@code allowedOriginRules} parameter.
     *
     * <p>This method should only be called if {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#DOCUMENT_START_SCRIPT}.
     *
     * @param webview The {@link WebView} instance that we are interacting with.
     * @param script The JavaScript script to be executed.
     * @param allowedOriginRules A set of matching rules for the allowed origins.
     * @return the {@link ScriptHandler}, which is a handle for removing the script.
     * @throws IllegalArgumentException If one of the {@code allowedOriginRules} is invalid.
     * @see #addWebMessageListener(WebView, String, Set, WebMessageListener)
     * @see ScriptHandler
     *
     * TODO(swestphal): unhide when ready.
     * @hide
     */
    @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
    @RequiresFeature(
            name = WebViewFeature.DOCUMENT_START_SCRIPT,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static @NonNull ScriptHandler addDocumentStartJavaScript(
            @NonNull WebView webview,
            @NonNull String script,
            @NonNull Set<String> allowedOriginRules) {
        final ApiFeature.NoFramework feature = WebViewFeatureInternal.DOCUMENT_START_SCRIPT;
        if (feature.isSupportedByWebView()) {
            return getProvider(webview)
                    .addDocumentStartJavaScript(script, allowedOriginRules.toArray(new String[0]));
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Gets the WebViewClient for the WebView argument.
     *
     * <p>
     * This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#GET_WEB_VIEW_CLIENT}.
     *
     * @return the WebViewClient, or a default client if not yet set
     */
    @RequiresFeature(name = WebViewFeature.GET_WEB_VIEW_CLIENT,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static @NonNull WebViewClient getWebViewClient(@NonNull WebView webview) {
        final ApiFeature.O feature = WebViewFeatureInternal.GET_WEB_VIEW_CLIENT;
        if (feature.isSupportedByFramework()) {
            return ApiHelperForO.getWebViewClient(webview);
        } else if (feature.isSupportedByWebView()) {
            return getProvider(webview).getWebViewClient();
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Gets the WebChromeClient.
     *
     * <p>
     * This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#GET_WEB_CHROME_CLIENT}.
     *
     * @return the WebChromeClient, or {@code null} if not yet set
     */
    @RequiresFeature(name = WebViewFeature.GET_WEB_CHROME_CLIENT,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static @Nullable WebChromeClient getWebChromeClient(@NonNull WebView webview) {
        final ApiFeature.O feature = WebViewFeatureInternal.GET_WEB_CHROME_CLIENT;
        if (feature.isSupportedByFramework()) {
            return ApiHelperForO.getWebChromeClient(webview);
        } else if (feature.isSupportedByWebView()) {
            return getProvider(webview).getWebChromeClient();
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Gets the WebView renderer associated with this WebView.
     *
     * <p>In Android O and above, WebView may run in "multiprocess"
     * mode. In multiprocess mode, rendering of web content is performed by
     * a sandboxed renderer process separate to the application process.
     * This renderer process may be shared with other WebViews in the
     * application, but is not shared with other application processes.
     *
     * <p>If WebView is running in multiprocess mode, this method returns a
     * handle to the renderer process associated with the WebView, which can
     * be used to control the renderer process.
     *
     * <p>This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#GET_WEB_VIEW_RENDERER}.
     *
     * @return the {@link WebViewRenderProcess} renderer handle associated
     *         with this {@link android.webkit.WebView}, or {@code null} if
     *         WebView is not running in multiprocess mode.
     */
    @RequiresFeature(name = WebViewFeature.GET_WEB_VIEW_RENDERER,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static @Nullable WebViewRenderProcess getWebViewRenderProcess(@NonNull WebView webview) {
        final ApiFeature.Q feature = WebViewFeatureInternal.GET_WEB_VIEW_RENDERER;
        if (feature.isSupportedByFramework()) {
            android.webkit.WebViewRenderProcess renderer = ApiHelperForQ.getWebViewRenderProcess(
                    webview);
            return renderer != null ? WebViewRenderProcessImpl.forFrameworkObject(renderer) : null;
        } else if (feature.isSupportedByWebView()) {
            return getProvider(webview).getWebViewRenderProcess();
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Sets the renderer client object associated with this WebView.
     *
     * <p>The renderer client encapsulates callbacks relevant to WebView renderer
     * state. See {@link WebViewRenderProcessClient} for details.
     *
     * <p>Although many WebView instances may share a single underlying renderer, and renderers may
     * live either in the application process, or in a sandboxed process that is isolated from
     * the application process, instances of {@link WebViewRenderProcessClient} are set per-WebView.
     * Callbacks represent renderer events from the perspective of this WebView, and may or may
     * not be correlated with renderer events affecting other WebViews.
     *
     * <p>The renderer client encapsulates callbacks relevant to WebView renderer
     * state. See {@link WebViewRenderProcessClient} for details.
     *
     * <p>Although many WebView instances may share a single underlying renderer, and renderers may
     * live either in the application process, or in a sandboxed process that is isolated from
     * the application process, instances of {@link WebViewRenderProcessClient} are set per-WebView.
     * Callbacks represent renderer events from the perspective of this WebView, and may or may
     * not be correlated with renderer events affecting other WebViews.
     *
     * <p>This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE}.
     *
     * @param webview the {@link WebView} on which to monitor responsiveness.
     * @param executor the {@link Executor} that will be used to execute callbacks.
     * @param webViewRenderProcessClient the {@link WebViewRenderProcessClient} to set for
     *                                   callbacks.
     */
    // WebViewRenderProcessClient is a callback class, so it should be last. See
    // https://issuetracker.google.com/issues/139770271.
    @SuppressLint("LambdaLast")
    @RequiresFeature(name = WebViewFeature.WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static void setWebViewRenderProcessClient(
            @NonNull WebView webview,
            @NonNull /* @CallbackExecutor */ Executor executor,
            @NonNull WebViewRenderProcessClient webViewRenderProcessClient) {
        final ApiFeature.Q feature =
                WebViewFeatureInternal.WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE;
        if (feature.isSupportedByFramework()) {
            ApiHelperForQ.setWebViewRenderProcessClient(webview, executor,
                    webViewRenderProcessClient);
        } else if (feature.isSupportedByWebView()) {
            getProvider(webview).setWebViewRenderProcessClient(
                    executor, webViewRenderProcessClient);
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Sets the renderer client object associated with this WebView.
     *
     * <p>See {@link WebViewCompat#setWebViewRenderProcessClient(WebView,Executor,WebViewRenderProcessClient)} for
     * details, with the following differences:
     *
     * <p>Callbacks will execute directly on the thread on which this WebView was instantiated.
     *
     * <p>Passing {@code null} for {@code webViewRenderProcessClient} will clear the renderer client
     * object for this WebView.
     *
     * <p>This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE}.
     *
     * @param webview the {@link WebView} on which to monitor responsiveness.
     * @param webViewRenderProcessClient the {@link WebViewRenderProcessClient} to set for
     *                                   callbacks.
     */
    @RequiresFeature(name = WebViewFeature.WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static void setWebViewRenderProcessClient(
            @NonNull WebView webview,
            @Nullable WebViewRenderProcessClient webViewRenderProcessClient) {
        final ApiFeature.Q feature =
                WebViewFeatureInternal.WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE;
        if (feature.isSupportedByFramework()) {
            ApiHelperForQ.setWebViewRenderProcessClient(webview, webViewRenderProcessClient);
        } else if (feature.isSupportedByWebView()) {
            getProvider(webview).setWebViewRenderProcessClient(null, webViewRenderProcessClient);
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Gets the renderer client object associated with this WebView.
     *
     * <p>This method should only be called if
     * {@link WebViewFeature#isFeatureSupported(String)}
     * returns true for {@link WebViewFeature#WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE}.
     *
     * @return the {@link WebViewRenderProcessClient} object associated with this WebView, if
     * one has been set via
     * {@link #setWebViewRenderProcessClient(WebView,WebViewRenderProcessClient)} or {@code null}
     * otherwise.
     */
    @RequiresFeature(name = WebViewFeature.WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static @Nullable WebViewRenderProcessClient getWebViewRenderProcessClient(
            @NonNull WebView webview) {
        final ApiFeature.Q feature =
                WebViewFeatureInternal.WEB_VIEW_RENDERER_CLIENT_BASIC_USAGE;
        if (feature.isSupportedByFramework()) {
            android.webkit.WebViewRenderProcessClient renderer =
                    ApiHelperForQ.getWebViewRenderProcessClient(webview);
            if (renderer == null
                    || !(renderer instanceof WebViewRenderProcessClientFrameworkAdapter)) {
                return null;
            }
            return ((WebViewRenderProcessClientFrameworkAdapter) renderer)
                .getFrameworkRenderProcessClient();
        } else if (feature.isSupportedByWebView()) {
            return getProvider(webview).getWebViewRenderProcessClient();
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Returns true if {@link WebView} is running in multi process mode.
     *
     * <p>In Android O and above, WebView may run in "multiprocess"
     * mode. In multiprocess mode, rendering of web content is performed by
     * a sandboxed renderer process separate to the application process.
     * This renderer process may be shared with other WebViews in the
     * application, but is not shared with other application processes.
     */
    @RequiresFeature(name = WebViewFeature.MULTI_PROCESS,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static boolean isMultiProcessEnabled() {
        final ApiFeature.NoFramework feature = WebViewFeatureInternal.MULTI_PROCESS;
        if (feature.isSupportedByWebView()) {
            return getFactory().getStatics().isMultiProcessEnabled();
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    /**
     * Gets the WebView variations encoded to be used as the X-Client-Data HTTP header.
     *
     * <p>The app is responsible for adding the X-Client-Data header to any request that may use
     * variations metadata, such as requests to Google web properties. The returned string will be a
     * base64 encoded ClientVariations proto:
     * https://source.chromium.org/chromium/chromium/src/+/main:components/variations/proto/client_variations.proto
     *
     * @return the variations header. The string may be empty if the header is not available.
     * @see WebView#loadUrl(String, java.util.Map<String, String>)
     */
    @RequiresFeature(
            name = WebViewFeature.GET_VARIATIONS_HEADER,
            enforcement = "androidx.webkit.WebViewFeature#isFeatureSupported")
    public static @NonNull String getVariationsHeader() {
        final ApiFeature.NoFramework feature = WebViewFeatureInternal.GET_VARIATIONS_HEADER;
        if (feature.isSupportedByWebView()) {
            return getFactory().getStatics().getVariationsHeader();
        } else {
            throw WebViewFeatureInternal.getUnsupportedOperationException();
        }
    }

    private static WebViewProviderFactory getFactory() {
        return WebViewGlueCommunicator.getFactory();
    }

    private static WebViewProviderBoundaryInterface createProvider(WebView webview) {
        return getFactory().createWebView(webview);
    }

    @SuppressWarnings({"JavaReflectionMemberAccess", "PrivateApi"})
    private static void checkThread(WebView webview) {
        if (Build.VERSION.SDK_INT >= 28) {
            Looper webViewLooper = ApiHelperForP.getWebViewLooper(webview);
            if (webViewLooper != Looper.myLooper()) {
                throw new RuntimeException("A WebView method was called on thread '"
                        + Thread.currentThread().getName() + "'. "
                        + "All WebView methods must be called on the same thread. "
                        + "(Expected Looper " + webViewLooper + " called on "
                        + Looper.myLooper() + ", FYI main Looper is " + Looper.getMainLooper()
                        + ")");
            }
        } else {
            try {
                Method checkThreadMethod = WebView.class.getDeclaredMethod("checkThread");
                checkThreadMethod.setAccessible(true);
                // WebView.checkThread() performs some logging and potentially throws an exception
                // if WebView is used on the wrong thread.
                checkThreadMethod.invoke(webview);
            } catch (NoSuchMethodException e) {
                throw new RuntimeException(e);
            } catch (IllegalAccessException e) {
                throw new RuntimeException(e);
            } catch (InvocationTargetException e) {
                throw new RuntimeException(e);
            }
        }
    }
}