flow_nav

Dynamic navigation and layout orchestration for Flutter.

flow_nav automatically adapts your app's layout and navigation behavior based on screen size — no manual breakpoint handling, no platform checks scattered across your codebase. Write once, run beautifully on phone, tablet, and desktop.

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Screenshots

Phone	Tablet	Desktop

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Features

• 📱 Adaptive AppBar — standard AppBar on phone, custom toolbar/menubar on tablet and desktop
• 🔀 Adaptive Navigation — full-screen push on phone, detail panel swap on large screens
• 🏗️ Adaptive Layout — single column (phone), split view (tablet), three-column (desktop)
• 🔌 Router Agnostic — works with the default Navigator, GoRouter, GetX, AutoRoute, or any custom router
• 🪶 Pure Logic, No UI Opinions — zero forced styling; bring your own widgets

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Getting Started

Add flow_nav to your pubspec.yaml:

dependencies:
  flow_nav: ^1.0.0

Then run:

flutter pub get

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Usage

1. Initialize in main.dart

Call FlowNavConfig.init() before runApp. This is where you configure your breakpoints and (optionally) your router hooks.

void main() {
  FlowNavConfig.init(
    tabletMinWidth: 600,
    desktopMinWidth: 1024,
  );
  runApp(MyApp());
}

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2. Router Integration

flow_nav is router-agnostic. Pass your own onPush / onPop callbacks and it will use them automatically on phone (detail panel swap is used on larger screens instead).

Default Navigator (no setup needed)

Works out of the box with no extra configuration.

GoRouter

FlowNavConfig.init(
  onPush: ({required context, required builder, fullscreenDialog = false}) {
    context.push('/detail');
    return Future.value(null);
  },
  onPop: (context) => context.pop(),
);

GetX

FlowNavConfig.init(
  onPush: ({required context, required builder, fullscreenDialog = false}) {
    return Get.to(() => builder(context));
  },
  onPop: (_) => Get.back(),
);

AutoRoute

FlowNavConfig.init(
  onPush: ({required context, required builder, fullscreenDialog = false}) {
    return context.router.push(MyRoute());
  },
  onPop: (context) => context.router.pop(),
);

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3. Use FlowScaffold

Replace your standard Scaffold with FlowScaffold. It handles the layout columns automatically.

class MyHomePage extends StatefulWidget {
  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  Widget? _detail;

  @override
  Widget build(BuildContext context) {
    return FlowScaffold(
      appBar: FlowAppBar(
        title: Text('My App'),
        toolbarWidget: MyDesktopToolbar(), // shown only on tablet/desktop
      ),
      body: MyListView(
        onItemTap: (item) {
          FlowNavController.open(
            context: context,
            builder: (_) => DetailPage(item: item),
            // Called on tablet/desktop — swap the detail panel instead of pushing
            onDetailOpen: (widget) => setState(() => _detail = widget),
          );
        },
      ),
      detailPanel: _detail,   // shown beside body on tablet/desktop
      sidebar: MySidebar(),   // shown only on desktop (left column)
    );
  }
}

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API Reference

FlowNavConfig.init()

Configures global settings. Call once before runApp.

Parameter	Type	Default	Description
tabletMinWidth	double	600	Minimum width to enter tablet layout
desktopMinWidth	double	1024	Minimum width to enter desktop layout
bodyMaxWidth	double?	null	Max width of content area
bodyPadding	EdgeInsets	EdgeInsets.zero	Inner padding for body
bodyMargin	EdgeInsets	EdgeInsets.zero	Outer margin for body
onPush	Function?	null	Custom navigation push (for GoRouter, GetX, etc.)
onPop	Function?	null	Custom navigation pop

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FlowScaffold

The main adaptive scaffold widget.

Property	Type	Description
appBar	PreferredSizeWidget?	Adaptive AppBar — shown on phone, converted to toolbar on larger screens
body	Widget	Main content (list, grid, etc.)
detailPanel	Widget?	Detail view shown beside body on tablet/desktop
sidebar	Widget?	Left sidebar shown only on desktop
sidebarWidth	double	Sidebar width (default: 240)
bodyPanelWidth	double	List panel width on tablet/desktop (default: 320)
maxWidth	double?	Max width of entire content area
bodyPadding	EdgeInsets?	Inner padding for body panel
bodyMargin	EdgeInsets?	Outer margin for body panel
backgroundColor	Color?	Scaffold background color
emptyDetail	Widget?	Placeholder shown when no detail is selected
bottomNavigationBar	Widget?	Bottom nav (phone/tablet only)
floatingActionButton	Widget?	FAB
drawer	Widget?	Drawer (phone/tablet)
forceScreenType	FlowScreenType?	Override screen type (useful for testing/previews)
bodyAlign	FlowBodyAlign	Align body when maxWidth is set (start or center)

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FlowAppBar

An adaptive AppBar that renders as a standard AppBar on phone and as a custom toolbar widget on larger screens.

FlowAppBar(
  title: Text('My App'),
  toolbarWidget: Row(
    children: [
      Text('My App', style: TextStyle(fontSize: 18)),
      Spacer(),
      IconButton(icon: Icon(Icons.settings), onPressed: () {}),
    ],
  ),
)

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FlowNavController.open()

The primary way to navigate to a detail view. Automatically pushes a new route on phone, or calls onDetailOpen on tablet/desktop.

FlowNavController.open(
  context: context,
  builder: (_) => DetailPage(item: item),
  onDetailOpen: (widget) => setState(() => _detail = widget),
  fullscreenDialog: false, // optional
);

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FlowNavBreakpoint.of(context)

Returns the current FlowScreenType for the given context. Useful for conditional rendering outside of FlowScaffold.

final screenType = FlowNavBreakpoint.of(context);

if (screenType == FlowScreenType.phone) {
  // phone-specific logic
}

FlowScreenType values: phone, tablet, desktop

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Layout Behavior Summary

Feature	Phone	Tablet	Desktop
AppBar	Standard AppBar	Toolbar at top of split view	Toolbar at top of content area
Layout	Single column	Body + Detail panel	Sidebar + Body + Detail panel
Navigation	Full-screen push	Detail panel swap	Detail panel swap
Bottom nav	✅ Shown	❌ Hidden	❌ Hidden
Drawer	✅ Shown	✅ Shown	❌ Hidden

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Requirements

• Dart SDK: ^3.6.0
• Flutter: >=3.0.0

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Contributing

Contributions are welcome! Please open an issue or pull request on GitHub.

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License

MIT