com.vaadin.flow.router.internal

Class AbstractNavigationStateRenderer

java.lang.Object

com.vaadin.flow.router.internal.AbstractNavigationStateRenderer

All Implemented Interfaces:

NavigationHandler, Serializable

Direct Known Subclasses:

ErrorStateRenderer, NavigationStateRenderer

public abstract class AbstractNavigationStateRenderer
extends Object
implements NavigationHandler

Base class for navigation handlers that target a navigation state.

For internal use only. May be renamed or removed in a future release.

Since:

1.0

Author:

Vaadin Ltd

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AbstractNavigationStateRenderer(NavigationState navigationState) Creates a new renderer for the given navigation state.

Method Summary

Modifier and Type	Method and Description
protected abstract boolean	eventActionsSupported() Checks whether this renderer should reroute or postpone navigation based on results from event listeners.
NavigationState	getNavigationState() Gets the targeted navigation state.
protected abstract List<Class<? extends RouterLayout>>	getRouterLayoutTypes(Class<? extends Component> routeTargetType, Router router) Gets the router layout types to show for the given route target type, starting from the parent layout immediately wrapping the route target type.
int	handle(NavigationEvent event) Handles the navigation event.
protected abstract void	notifyNavigationTarget(Component componentInstance, NavigationEvent navigationEvent, BeforeEnterEvent beforeEnterEvent, LocationChangeEvent locationChangeEvent) Notify the navigation target about the status of the navigation.
static void	purgeInactiveUIPreservedChainCache(UI inactiveUI) Removes preserved component cache for an inactive UI.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AbstractNavigationStateRenderer

public AbstractNavigationStateRenderer(NavigationState navigationState)

Creates a new renderer for the given navigation state.

Parameters:

navigationState - the target navigation state

Method Detail

getNavigationState

public NavigationState getNavigationState()

Gets the targeted navigation state.

Returns:

the targeted navigation state

handle

public int handle(NavigationEvent event)

Description copied from interface: NavigationHandler

Handles the navigation event.

Specified by:

handle in interface NavigationHandler

Parameters:

event - the navigation event to handle

Returns:

the HTTP status code to return to the client if handling an initial rendering request

notifyNavigationTarget

protected abstract void notifyNavigationTarget(Component componentInstance,
                                               NavigationEvent navigationEvent,
                                               BeforeEnterEvent beforeEnterEvent,
                                               LocationChangeEvent locationChangeEvent)

Notify the navigation target about the status of the navigation.

Parameters:

componentInstance - the navigation target instance

navigationEvent - the low level navigation event that is being processed

beforeEnterEvent - the before enter event that will be fired unless navigation is rerouted

locationChangeEvent - the location change event that will be fired unless navigation is rerouted

getRouterLayoutTypes

protected abstract List<Class<? extends RouterLayout>> getRouterLayoutTypes(Class<? extends Component> routeTargetType,
                                                                            Router router)

Gets the router layout types to show for the given route target type, starting from the parent layout immediately wrapping the route target type.

Parameters:

routeTargetType - component type that will be shown

router - used router instance

Returns:

a list of parent RouterLayout types, not null

eventActionsSupported

protected abstract boolean eventActionsSupported()

Checks whether this renderer should reroute or postpone navigation based on results from event listeners. Furthermore, the before leave event is not fired at all if event actions are not supported.

Returns:

true to support event actions; false otherwise.

purgeInactiveUIPreservedChainCache

public static void purgeInactiveUIPreservedChainCache(UI inactiveUI)

Removes preserved component cache for an inactive UI.

Parameters:

inactiveUI - the inactive UI

Throws:

IllegalStateException - if the UI is not in closing state