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

Method Summary

Modifier and Type	Method	Description
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.
protected List<Class<? extends RouterLayout>>	getTargetParentLayouts(RouteTarget routeTarget, RouteRegistry registry, String path)	Get the parentLayouts for given routeTarget or use an applicable @Layout when no parentLayouts defined and target is a Route annotated target with autoLayout enabled and no layout set.
int	handle(NavigationEvent event)	Handles the navigation event.
protected Optional<Integer>	handleTriggeredBeforeEvent(NavigationEvent event, BeforeEvent beforeEvent)	Handle a BeforeEvent after if has been triggered to an observer.
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.
protected void	pushHistoryState(NavigationEvent event)
protected boolean	shouldPushHistoryState(NavigationEvent event)

Methods inherited from class java.lang.Object

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

Constructor Details

AbstractNavigationStateRenderer

public AbstractNavigationStateRenderer(NavigationState navigationState)

Creates a new renderer for the given navigation state.

Parameters:

navigationState - the target navigation state

Method Details

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

getTargetParentLayouts

protected List<Class<? extends RouterLayout>> getTargetParentLayouts(RouteTarget routeTarget,
 RouteRegistry registry,
 String path)

Get the parentLayouts for given routeTarget or use an applicable @Layout when no parentLayouts defined and target is a Route annotated target with autoLayout enabled and no layout set.

Parameters:

routeTarget - RouteTarget to get parents for

registry - Registry in use

path - request path

Returns:

List of parent layouts

pushHistoryState

protected void pushHistoryState(NavigationEvent event)

shouldPushHistoryState

protected boolean shouldPushHistoryState(NavigationEvent event)

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

handleTriggeredBeforeEvent

protected Optional<Integer> handleTriggeredBeforeEvent(NavigationEvent event,
 BeforeEvent beforeEvent)

Handle a BeforeEvent after if has been triggered to an observer.

Parameters:

event - the navigation event being handled.

beforeEvent - the BeforeLeaveEvent or BeforeEnterEvent being triggered to an observer.

Returns:

an HTTP status code wrapped as an Optional. If the Optional is empty, the process will proceed with next observer or just move forward, otherwise the process will return immediately with the provided http code.

See Also:

• HttpStatusCode

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