WebViewCompat

createWebMessageChannel

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.

getCurrentWebViewPackage

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WebView was loaded right now will be returned; this does not cause WebView to be loaded, so this information may become outdated at any time.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.

getSafeBrowsingPrivacyPolicyUrl

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.

postVisualStateCallback

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 WebView.onDraw(Canvas) 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 WebView 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

• the video tag

To guarantee that the WebView 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 WebView's visibility is set to VISIBLE then * the WebView must be attached to the view hierarchy.
• If the WebView's visibility is set to INVISIBLE then the WebView must be attached to the view hierarchy and must be made VISIBLE from the WebViewCompat.VisualStateCallback.onComplete(long) method.
• If the WebView's visibility is set to GONE then the WebView must be attached to the view hierarchy and its LayoutParams'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 WebView is off screen to avoid flickering. See WebSettings.setOffscreenPreRaster(boolean) 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.

postWebMessage

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.

setSafeBrowsingWhitelist

public static void setSafeBrowsingWhitelist (List<String> hosts, 
                ValueCallback<Boolean> callback)

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:

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.

startSafeBrowsing

public static void startSafeBrowsing (Context context, 
                ValueCallback<Boolean> 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 WebSettings.setSafeBrowsingEnabled(boolean). 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.