NavigationListener

Added in 1.15.0

Kotlin |Java

@WebNavigationClient.ExperimentalNavigationCallback
public interface NavigationListener

Page identification and lifecycle APIs.

This class provides callbacks to identify the different stages of navigation. For more information about the navigation lifecycle, please see the Life of a Navigation Presentation.

Note: These navigation callbacks only fire for navigations happening on the main frame.

Navigation lifecycle events:

onNavigationStarted
Potentially zero or more onNavigationRedirected events
onNavigationCompleted
If the navigation commits and is not a same-document navigation, potentially any combination and order of zero or one of each of:

Summary

Public methods
`default void`	`onFirstContentfulPaint(@NonNull Page page, long loadTimeUs)` Called when the page achieves "First Contentful Paint".
`default void`	`onFirstContentfulPaintMillis(@NonNull Page page, long durationMillis)` Called when the page achieves "First Contentful Paint".
`default void`	`onLargestContentfulPaintMillis(@NonNull Page page, long durationMillis)` Called when the page fires a "Largest Contentful Paint" event.
`default void`	`onNavigationCompleted(@NonNull Navigation navigation)` Called when a navigation completes.
`default void`	`onNavigationRedirected(@NonNull Navigation navigation)` Called when a navigation is redirected.
`default void`	`onNavigationStarted(@NonNull Navigation navigation)` Called when a navigation starts, including same-document navigations.
`default void`	`onPageDeleted(@NonNull Page page)` Called when any Page is evicted/destroyed.
`default void`	`onPageDomContentLoadedEvent(@NonNull Page page)` Called when the `DOMContentLoaded` event is fired for the current page.
`default void`	`onPageLoadEvent(@NonNull Page page)` Called when the `window.load` event is fired for the current page.
`default void`	`onPerformanceMarkMillis( @NonNull Page page, @NonNull String markName, long markTimeMillis )` Called when the page registers a performance mark.

Public methods

onFirstContentfulPaint

Added in 1.15.0

default void onFirstContentfulPaint(@NonNull Page page, long loadTimeUs)

Called when the page achieves "First Contentful Paint".

See First Contentful Paint (FCP) for a definition.

Parameters
`@NonNull Page page`	The Page for which the First Contentful Paint occurred.
`long loadTimeUs`	Navigation to First Contentful Paint load time in microseconds.

onFirstContentfulPaintMillis

Added in 1.16.0-alpha03

default void onFirstContentfulPaintMillis(@NonNull Page page, long durationMillis)

Called when the page achieves "First Contentful Paint".

See First Contentful Paint (FCP) for a definition.

This method is called only if NAVIGATION_LISTENER_V2 is supported. You can check whether that flag is supported using isFeatureSupported.

Parameters
`@NonNull Page page`	The Page for which the First Contentful Paint occurred.
`long durationMillis`	Navigation to First Contentful Paint duration in milliseconds.

onLargestContentfulPaintMillis

Added in 1.16.0-alpha03

default void onLargestContentfulPaintMillis(@NonNull Page page, long durationMillis)

Called when the page fires a "Largest Contentful Paint" event.

See Largest Contentful Paint (LCP) for a definition.

This method is called only if NAVIGATION_LISTENER_V2 is supported. You can check whether that flag is supported using isFeatureSupported.

Parameters
`@NonNull Page page`	The Page for which the Largest Contentful Paint occurred.
`long durationMillis`	Navigation to Largest Contentful Paint duration in milliseconds.

Added in 1.15.0

default void onNavigationCompleted(@NonNull Navigation navigation)

Called when a navigation completes.

The navigation might not have actually committed (e.g., results in 204/download/cancelled), but those that do they will have committed by this point.

Parameters
`@NonNull Navigation navigation`	The Navigation object representing the completed navigation.

Added in 1.15.0

default void onNavigationRedirected(@NonNull Navigation navigation)

Called when a navigation is redirected.

Parameters
`@NonNull Navigation navigation`	The Navigation object representing the redirected navigation.

Added in 1.15.0

default void onNavigationStarted(@NonNull Navigation navigation)

Called when a navigation starts, including same-document navigations.

Note: These navigation callbacks only fire for navigations happening on the main frame.

Parameters
`@NonNull Navigation navigation`	The Navigation object representing the started navigation.

onPageDeleted

Added in 1.15.0

default void onPageDeleted(@NonNull Page page)

Called when any Page is evicted/destroyed. This can occur immediately on navigation, or later if the page is BFCached and subsequently evicted.

Parameters
`@NonNull Page page`	The Page that was evicted or destroyed.

onPageDomContentLoadedEvent

Added in 1.15.0

default void onPageDomContentLoadedEvent(@NonNull Page page)

Called when the DOMContentLoaded event is fired for the current page.

Parameters
`@NonNull Page page`	The Page for which the `DOMContentLoaded` event fired.

onPageLoadEvent

Added in 1.15.0

default void onPageLoadEvent(@NonNull Page page)

Called when the window.load event is fired for the current page.

Parameters
`@NonNull Page page`	The Page for which the `window.load` event fired.

onPerformanceMarkMillis

Added in 1.16.0-alpha03

default void onPerformanceMarkMillis(
    @NonNull Page page,
    @NonNull String markName,
    long markTimeMillis
)

Called when the page registers a performance mark.

See Performance: mark() method for a definition.

This method is called only if NAVIGATION_LISTENER_V2 is supported. You can check whether that flag is supported using isFeatureSupported.

Parameters
`@NonNull Page page`	The Page for which the performance mark was registered.
`@NonNull String markName`	The name of the performance mark.
`long markTimeMillis`	The time of the performance mark in milliseconds since Performance.timeOrigin.