Interface NavRenderer

All Known Implementing Classes:

ExpandingTouchNavRenderer, FlyoutRailNavRenderer, HeaderTabsNavRenderer, ScrollingTouchNavRenderer, SideNavDrawerNavRenderer, SideRailNavRenderer, TouchBarNavRenderer

public interface NavRenderer

Builds and updates the nav-item content for one of AppNavLayout's five device/orientation scenarios (desktop, tablet portrait, tablet landscape, phone portrait, phone landscape), placing it into whichever of AppNavLayout's named locations (see NavSlots) is appropriate. Register an implementation via AppNavLayout.setDesktopNavRenderer(Supplier), AppNavLayout.setTabletPortraitNavRenderer(Supplier), AppNavLayout.setTabletLandscapeNavRenderer(Supplier) (or the AppNavLayout.setTabletNavRenderer(Supplier) convenience setter), AppNavLayout.setPhonePortraitNavRenderer(Supplier), or AppNavLayout.setPhoneLandscapeNavRenderer(Supplier) (or AppNavLayout.setPhoneNavRenderer(Supplier)) to replace the default for that scenario.

Deliberately decoupled from nav organization: a renderer receives an already-configured NavGrouper and never influences or queries how the tree is grouped.

Method Summary

Modifier and Type	Method	Description
NavType	navType()	The chrome this renderer requires — determines which NavStrategy gets built for whichever scenario this renderer is configured for.
default String	railWidth()	The rail's own width, as a CSS length — consulted only when navType() is NavType.RAIL.
void	render(NavRenderContext context)	Builds or updates this renderer's content for the current nav state.

Method Details

render

void render(NavRenderContext context)

Builds or updates this renderer's content for the current nav state. Called once when this scenario becomes active, again on every completed navigation, and again whenever nav configuration changes (grouper swap, path matcher change). The implementation decides which slot(s) in context.slots() to populate and how — including any overflow or drill-down scaffolding it needs (a "More…" popover, a chevron, a swipeable container, etc).

navType

NavType navType()

The chrome this renderer requires — determines which NavStrategy gets built for whichever scenario this renderer is configured for. Not a free choice: a renderer's render(NavRenderContext) implementation already assumes one specific NavSlots accessor is live (e.g. SideRailNavRenderer only ever populates NavSlots.sideRail()), and that slot is only live under the matching NavType's strategy. This method makes that assumption explicit instead of leaving it to silently mismatch — a renderer configured for a scenario whose resolved chrome doesn't match its own navType() would otherwise render into a slot that's never attached to the page, with nothing to indicate why.

railWidth

default String railWidth()

The rail's own width, as a CSS length — consulted only when navType() is NavType.RAIL. Default matches the built-in rail renderers' own icon-and-label-only content. Override when a renderer's items need more (or less) horizontal room than that — e.g. FlyoutRailNavRenderer's own trailing chevron box.