intelligencezuloo.blogg.se - Flutter scaffold bottomnavigationbar

#FLUTTER SCAFFOLD BOTTOMNAVIGATIONBAR UPDATE#

To make this possible, we only needed a few ingredients: Note how the counter value is preserved when switching between tabs Here’s what the end result looks like: Stateful nested navigation example. Stateful nested navigation “just works”, and each branch remembers its own state (all the pages inside each tab).

We can easily switch between tabs (using navigationShell.goBranch) by writing only stateless code.

Stateful Nested Navigation: SummaryĪs it turns out, the code above already solves these problems: That’s because all the stateful logic lives inside the StatefulNavigationShell class itself - a widget that manages the state of a StatefulShellRoute, by creating a separate Navigator for each of its nested branches.

#FLUTTER SCAFFOLD BOTTOMNAVIGATIONBAR UPDATE#

What’s great about using navigationShell is that we don’t have to store and update any state (such as the selected index) inside our ScaffoldWithNestedNavigation (which is a StatelessWidget).

call the goBranch method so we can switch to a new branch when a new destination is selected.

retrieve the currentIndex that we can pass to the NavigationBar.

currentIndex, destinations: const, onDestinationSelected: _goBranch, ), )

Scaffold ( body: navigationShell, bottomNavigationBar: NavigationBar ( selectedIndex: navigationShell. settings )), ], onDestinationSelected: ( index ) Īs we can see, the navigationShell is passed directly to the body of the Scaffold:

home )), NavigationDestination ( label: 'Section B', icon: Icon ( Icons. Scaffold ( body: /* TODO: decide which page to show, depending on the selected index */, bottomNavigationBar: NavigationBar ( selectedIndex: /* TODO: where does this come from? */, destinations: const widget NavigationDestination ( label: 'Section A', icon: Icon ( Icons.