framework/view/page_group library

Classes

PageGroup
a collection of pages grouped under a navigation menu
PageGroupState
PageGroupWidget
wrapper widget to enable a Page to get the navigation menu from its parent PageGroup We need this because the menu (i.e. drawer) is determined at the PageGroup level, but need to be injected under each child Page to render.
ViewGroupNotifier

Properties

viewGroupNotifier ViewGroupNotifier
final

Functions

resolveNavigateViewGroupTabIndex(int viewIndex, int menuLen) int
Resolves the tab index for NavigateViewGroupAction before PageController.jumpToPage. Clamps when the menu has items; otherwise preserves viewIndex (the PageGroup ancestor may not be mounted yet).
safeViewGroupPayloadIndex(int index, int payloadLength) int
Clamps a ViewGroup tab index for indexing PageGroupState.pagePayloads and IndexedStack children. Call sites must use this when the global viewGroupNotifier may hold a stale index (for example after restoring from background storage when the menu definition has fewer tabs than before).