CustomTabsCallback

public static final int ACTIVITY_LAYOUT_STATE_BOTTOM_SHEET = 1

The activity is being displayed as a bottom-sheet at its initial height.

public static final int ACTIVITY_LAYOUT_STATE_BOTTOM_SHEET_MAXIMIZED = 2

The activity is being displayed as a bottom-sheet at its maximized height.

public static final int ACTIVITY_LAYOUT_STATE_FULL_SCREEN = 5

The activity is being displayed over the whole window. This will be the case when a Partial Custom Tab bottom sheet or side sheet cannot be displayed due to minimum width restrictions (see EXTRA_INITIAL_ACTIVITY_WIDTH_PX) or browser limitations.

public static final int ACTIVITY_LAYOUT_STATE_SIDE_SHEET = 3

The activity is being displayed as a side-sheet at its initial width.

public static final int ACTIVITY_LAYOUT_STATE_SIDE_SHEET_MAXIMIZED = 4

The activity is being displayed as a side-sheet at its maximized width.

public static final int ACTIVITY_LAYOUT_STATE_UNKNOWN = 0

The activity's layout state is unknown. This value communicates an error state, the fact that the state cannot be determined, or that the browser implementation does not provide support for this feature.

public static final int NAVIGATION_ABORTED = 4

Sent when loading was aborted by a user action before it finishes like clicking on a link or refreshing the page.

public static final int NAVIGATION_FAILED = 3

Sent when the tab couldn't finish loading due to a failure.

public static final int NAVIGATION_FINISHED = 2

Sent when the tab has finished loading a page.

public static final int NAVIGATION_STARTED = 1

Sent when the tab has started loading a page.

public static final int TAB_HIDDEN = 6

Sent when the tab becomes hidden.

public static final int TAB_SHOWN = 5

Sent when the tab becomes visible.

public void extraCallback(@NonNull String callbackName, @Nullable Bundle args)

Unsupported callbacks that may be provided by the implementation.

Note:Clients should never rely on this callback to be called and/or to have a defined behavior, as it is entirely implementation-defined and not supported.

This can be used by implementations to add extra callbacks, for testing or experimental purposes.

public @Nullable Bundle extraCallbackWithResult(
    @NonNull String callbackName,
    @Nullable Bundle args
)

The same as extraCallback, except that this method allows the custom tabs provider to return a result. A return value of null will be used to signify that the client does not know how to handle the callback. As optional best practices, KEY_SUCCESS could be use to identify that callback was *successfully* handled. For example, when returning a message with result:

    Bundle result = new Bundle();
    result.putString("message", message);
    if (success)
        result.putBoolean(CustomTabsService#KEY_SUCCESS, true);
    return result;

    Bundle result = extraCallbackWithResult(callbackName, args);
    if (result.getBoolean(CustomTabsService#KEY_SUCCESS)) {
        // callback was successfully handled
    }

public void onActivityLayout(
    @Dimension(unit = 1) int left,
    @Dimension(unit = 1) int top,
    @Dimension(unit = 1) int right,
    @Dimension(unit = 1) int bottom,
    int state,
    @NonNull Bundle extras
)

Called when the Partial Custom Tab's layout has changed. This callback is not applicable to Custom Tabs that are not launched with EXTRA_INITIAL_ACTIVITY_WIDTH_PX or EXTRA_INITIAL_ACTIVITY_HEIGHT_PX set to their intent.

public void onActivityResized(
    @Dimension(unit = 1) int height,
    @Dimension(unit = 1) int width,
    @NonNull Bundle extras
)

Called when the tab is resized.

public void onMessageChannelReady(@Nullable Bundle extras)

Called when CustomTabsSession has requested a postMessage channel through requestPostMessageChannel and the channel is ready for sending and receiving messages on both ends.

public void onMinimized(@NonNull Bundle extras)

Called when the Custom Tab is minimized by the user such that it covers a small part of the screen.

public void onNavigationEvent(int navigationEvent, @Nullable Bundle extras)

To be called when a navigation event happens.

public void onPostMessage(@NonNull String message, @Nullable Bundle extras)

Called when a tab controlled by this CustomTabsSession has sent a postMessage. If postMessage() is called from a single thread, then the messages will be posted in the same order. When received on the client side, it is the client's responsibility to preserve the ordering further.

public void onRelationshipValidationResult(
    @CustomTabsService.Relation int relation,
    @NonNull Uri requestedOrigin,
    boolean result,
    @Nullable Bundle extras
)

Called when a relationship validation result is available.

public void onUnminimized(@NonNull Bundle extras)

Called when the Custom Tab is unminimized by the user such that it returns back to its original state.

public void onWarmupCompleted(@NonNull Bundle extras)

Called when the browser process finished warming up initiated by warmup.