### Track Visible Lists with ExtendedVisibilityDetector

Source: https://github.com/fluttercandies/extended_nested_scroll_view/blob/master/README.md

This example illustrates the usage of `ExtendedVisibilityDetector` from the `extended_nested_scroll_view` package. It allows developers to identify which list within a tab view is currently visible by assigning a unique key to each detector.

```dart
   ExtendedVisibilityDetector(
      uniqueKey: const Key('Tab1'),
      child: ListView(),
   )

```

--------------------------------

### Flutter Dart Example: ExtendedNestedScrollView with TabBar

Source: https://context7.com/fluttercandies/extended_nested_scroll_view/llms.txt

Demonstrates setting up an ExtendedNestedScrollView that contains a TabBar in its header and a TabBarView in its body. It uses `onlyOneScrollInBody: true` to manage scroll synchronization and `PageStorageKey` to preserve scroll positions for each tab's content.

```dart
import 'package:extended_nested_scroll_view/extended_nested_scroll_view.dart';
import 'package:flutter/material.dart';

class TabBarExample extends StatefulWidget {
  @override
  _TabBarExampleState createState() => _TabBarExampleState();
}

class _TabBarExampleState extends State<TabBarExample>
    with TickerProviderStateMixin {
  late TabController tabController;

  @override
  void initState() {
    super.initState();
    tabController = TabController(length: 3, vsync: this);
  }

  @override
  void dispose() {
    tabController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final double statusBarHeight = MediaQuery.of(context).padding.top;
    final double pinnedHeaderHeight = statusBarHeight + kToolbarHeight;

    return Scaffold(
      body: ExtendedNestedScrollView(
        // Prevent multiple scroll positions from scrolling together
        onlyOneScrollInBody: true,
        pinnedHeaderSliverHeightBuilder: () => pinnedHeaderHeight,
        headerSliverBuilder: (BuildContext context, bool innerBoxIsScrolled) {
          return <Widget>[
            SliverAppBar(
              pinned: true,
              expandedHeight: 200.0,
              title: Text('Profile'),
              bottom: TabBar(
                controller: tabController,
                tabs: [
                  Tab(text: 'Posts'),
                  Tab(text: 'Photos'),
                  Tab(text: 'Videos'),
                ],
              ),
            ),
          ];
        },
        body: TabBarView(
          controller: tabController,
          children: [
            // Use PageStorageKey to maintain scroll position
            ListView.builder(
              key: PageStorageKey<String>('Posts'),
              physics: ClampingScrollPhysics(),
              itemCount: 50,
              itemBuilder: (context, index) {
                return ListTile(title: Text('Post $index'));
              },
            ),
            ListView.builder(
              key: PageStorageKey<String>('Photos'),
              physics: ClampingScrollPhysics(),
              itemCount: 50,
              itemBuilder: (context, index) {
                return Container(
                  height: 200,
                  color: Colors.grey[300],
                  margin: EdgeInsets.all(8),
                  child: Center(child: Text('Photo $index')),
                );
              },
            ),
            ListView.builder(
              key: PageStorageKey<String>('Videos'),
              physics: ClampingScrollPhysics(),
              itemCount: 50,
              itemBuilder: (context, index) {
                return ListTile(title: Text('Video $index'));
              },
            ),
          ],
        ),
      ),
    );
  }
}

```

--------------------------------

### Implement Active Tab Detection with ExtendedVisibilityDetector in Flutter

Source: https://context7.com/fluttercandies/extended_nested_scroll_view/llms.txt

This Dart code demonstrates how to use ExtendedVisibilityDetector to identify the currently active and visible tab within a TabBarView. It requires the 'extended_nested_scroll_view' and 'flutter/material.dart' packages. The example sets up a Scaffold with an ExtendedNestedScrollView containing a TabBarView, where each tab's content is wrapped in an ExtendedVisibilityDetector.

```dart
import 'package:extended_nested_scroll_view/extended_nested_scroll_view.dart';
import 'package:flutter/material.dart';

class VisibilityExample extends StatefulWidget {
  @override
  _VisibilityExampleState createState() => _VisibilityExampleState();
}

class _VisibilityExampleState extends State<VisibilityExample>
    with TickerProviderStateMixin {
  late TabController tabController;

  @override
  void initState() {
    super.initState();
    tabController = TabController(length: 2, vsync: this);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: ExtendedNestedScrollView(
        onlyOneScrollInBody: true,
        pinnedHeaderSliverHeightBuilder: () {
          return MediaQuery.of(context).padding.top + kToolbarHeight;
        },
        headerSliverBuilder: (context, innerBoxIsScrolled) {
          return [
            SliverAppBar(
              pinned: true,
              title: Text('Visibility Tracking'),
              bottom: TabBar(
                controller: tabController,
                tabs: [Tab(text: 'Tab 1'), Tab(text: 'Tab 2')],
              ),
            ),
          ];
        },
        body: TabBarView(
          controller: tabController,
          children: [
            ExtendedVisibilityDetector(
              uniqueKey: Key('Tab1'),
              child: ListView.builder(
                key: PageStorageKey<String>('Tab1'),
                itemCount: 100,
                itemBuilder: (context, index) {
                  return ListTile(title: Text('Tab 1 - Item $index'));
                },
              ),
            ),
            ExtendedVisibilityDetector(
              uniqueKey: Key('Tab2'),
              child: ListView.builder(
                key: PageStorageKey<String>('Tab2'),
                itemCount: 100,
                itemBuilder: (context, index) {
                  return ListTile(title: Text('Tab 2 - Item $index'));
                },
              ),
            ),
          ],
        ),
      ),
    );
  }

  @override
  void dispose() {
    tabController.dispose();
    super.dispose();
  }
}

```

--------------------------------

### Control Scrolling with GlobalKey in ExtendedNestedScrollView

Source: https://context7.com/fluttercandies/extended_nested_scroll_view/llms.txt

Shows how to use a GlobalKey to access the scroll controllers of an ExtendedNestedScrollView for programmatic scrolling. This allows actions like scrolling to the top of the content.

```dart
import 'package:extended_nested_scroll_view/extended_nested_scroll_view.dart';
import 'package:flutter/material.dart';

class ScrollControlExample extends StatefulWidget {
  @override
  _ScrollControlExampleState createState() => _ScrollControlExampleState();
}

class _ScrollControlExampleState extends State<ScrollControlExample> {
  final GlobalKey<ExtendedNestedScrollViewState> nestedScrollKey =
      GlobalKey<ExtendedNestedScrollViewState>();

  void scrollToTop() {
    // Access outer controller to scroll to top
    nestedScrollKey.currentState?.outerController.animateTo(
      0.0,
      duration: Duration(milliseconds: 500),
      curve: Curves.easeOut,
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: ExtendedNestedScrollView(
        key: nestedScrollKey,
        pinnedHeaderSliverHeightBuilder: () {
          return MediaQuery.of(context).padding.top + kToolbarHeight;
        },
        headerSliverBuilder: (context, innerBoxIsScrolled) {
          return [
            SliverAppBar(
              pinned: true,
              expandedHeight: 200.0,
              title: Text('Scroll Control'),
            ),
          ];
        },
        body: ListView.builder(
          itemCount: 100,
          itemBuilder: (context, index) {
            return ListTile(
              title: Text('Item $index'),
            );
          },
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: scrollToTop,
        child: Icon(Icons.arrow_upward),
        tooltip: 'Scroll to top',
      ),
    );
  }
}

```

--------------------------------

### Implement Floating Headers with ExtendedNestedScrollView

Source: https://context7.com/fluttercandies/extended_nested_scroll_view/llms.txt

Demonstrates how to enable floating header slivers in ExtendedNestedScrollView for responsive app bar behavior. This allows the header to float and reappear as the user scrolls.

```dart
import 'package:extended_nested_scroll_view/extended_nested_scroll_view.dart';
import 'package:flutter/material.dart';

class FloatingHeaderExample extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: ExtendedNestedScrollView(
        // Enable floating behavior for header slivers
        floatHeaderSlivers: true,
        scrollDirection: Axis.vertical,
        reverse: false,
        physics: BouncingScrollPhysics(),
        pinnedHeaderSliverHeightBuilder: () {
          return MediaQuery.of(context).padding.top + kToolbarHeight;
        },
        headerSliverBuilder: (context, innerBoxIsScrolled) {
          return [
            SliverAppBar(
              floating: true,
              snap: true,
              pinned: false,
              expandedHeight: 200.0,
              title: Text('Floating Header'),
              forceElevated: innerBoxIsScrolled,
              flexibleSpace: FlexibleSpaceBar(
                background: Image.network(
                  'https://example.com/header.jpg',
                  fit: BoxFit.cover,
                ),
              ),
            ),
          ];
        },
        body: ListView.builder(
          physics: ClampingScrollPhysics(),
          itemCount: 100,
          itemBuilder: (context, index) {
            return Card(
              margin: EdgeInsets.all(8),
              child: ListTile(
                leading: CircleAvatar(child: Text('$index')),
                title: Text('Item $index'),
                subtitle: Text('Subtitle for item $index'),
                trailing: Icon(Icons.arrow_forward_ios),
              ),
            );
          },
        ),
      ),
    );
  }
}

```

--------------------------------

### ExtendedNestedScrollView with Pinned Header in Dart

Source: https://context7.com/fluttercandies/extended_nested_scroll_view/llms.txt

Demonstrates basic usage of ExtendedNestedScrollView to configure a pinned header height, preventing overlap issues with content. Requires the 'extended_nested_scroll_view' package.

```dart
import 'package:extended_nested_scroll_view/extended_nested_scroll_view.dart';
import 'package:flutter/material.dart';

class BasicExample extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final double statusBarHeight = MediaQuery.of(context).padding.top;
    final double pinnedHeaderHeight = statusBarHeight + kToolbarHeight;

    return ExtendedNestedScrollView(
      // Fix pinned header overlap issue
      pinnedHeaderSliverHeightBuilder: () {
        return pinnedHeaderHeight;
      },
      headerSliverBuilder: (BuildContext context, bool innerBoxIsScrolled) {
        return <Widget>[
          SliverAppBar(
            pinned: true,
            expandedHeight: 200.0,
            title: Text('Extended Nested Scroll'),
            flexibleSpace: FlexibleSpaceBar(
              background: Image.network(
                'https://example.com/header.jpg',
                fit: BoxFit.cover,
              ),
            ),
          ),
        ];
      },
      body: ListView.builder(
        itemCount: 100,
        itemBuilder: (context, index) {
          return ListTile(
            title: Text('Item $index'),
          );
        },
      ),
    );
  }
}
```

--------------------------------

### Set Pinned Sliver Header Height in ExtendedNestedScrollView

Source: https://github.com/fluttercandies/extended_nested_scroll_view/blob/master/README.md

This snippet demonstrates how to define the total height of pinned sliver headers by implementing the `pinnedHeaderSliverHeightBuilder` callback in `ExtendedNestedScrollView`. It calculates the height based on the status bar, toolbar, and tab bar heights.

```dart
var tabBarHeight = primaryTabBar.preferredSize.height;
      var pinnedHeaderHeight =
          //statusBar height
          statusBarHeight +
              //pinned SliverAppBar height in header
              kToolbarHeight;

    ExtendedNestedScrollView(
        pinnedHeaderSliverHeightBuilder: () {
          return pinnedHeaderHeight;
        }
       )
       
```

--------------------------------

### Manage Inner Scrollables in ExtendedNestedScrollView

Source: https://github.com/fluttercandies/extended_nested_scroll_view/blob/master/README.md

This code snippet shows how to configure `ExtendedNestedScrollView` to manage scroll synchronization within its body, particularly when dealing with multiple inner scrollables in tab views. It highlights the use of `onlyOneScrollInBody` to control scroll position management, differentiating between `AutomaticKeepAliveClientMixin` and `PageStorageKey` strategies.

```dart
    ExtendedNestedScrollView(
       onlyOneScrollInBody: true,
    )

```

--------------------------------

### Implement Pull-to-Refresh in NestedScrollView Body (Dart)

Source: https://context7.com/fluttercandies/extended_nested_scroll_view/llms.txt

This Dart code snippet shows how to add pull-to-refresh to the body of an `ExtendedNestedScrollView`. It uses `PullToRefreshNotification` to handle the refresh logic and updates a `CustomScrollView` within a `TabBarView`. Dependencies include `extended_nested_scroll_view` and `pull_to_refresh_notification`.

```dart
import 'package:extended_nested_scroll_view/extended_nested_scroll_view.dart';
import 'package:flutter/material.dart';
import 'package:pull_to_refresh_notification/pull_to_refresh_notification.dart';

class PullToRefreshExample extends StatefulWidget {
  @override
  _PullToRefreshExampleState createState() => _PullToRefreshExampleState();
}

class _PullToRefreshExampleState extends State<PullToRefreshExample>
    with TickerProviderStateMixin {
  late TabController tabController;
  int itemCount = 30;
  DateTime lastRefreshTime = DateTime.now();

  @override
  void initState() {
    super.initState();
    tabController = TabController(length: 2, vsync: this);
  }

  @override
  Widget build(BuildContext context) {
    final double statusBarHeight = MediaQuery.of(context).padding.top;
    final double pinnedHeaderHeight = statusBarHeight + kToolbarHeight;

    return Scaffold(
      body: ExtendedNestedScrollView(
        pinnedHeaderSliverHeightBuilder: () => pinnedHeaderHeight,
        headerSliverBuilder: (context, innerBoxIsScrolled) {
          return [
            SliverAppBar(
              pinned: true,
              expandedHeight: 200.0,
              title: Text('Pull to Refresh'),
              flexibleSpace: FlexibleSpaceBar(
                background: Container(color: Colors.blue),
              ),
            ),
          ];
        },
        body: Column(
          children: [
            TabBar(
              controller: tabController,
              labelColor: Colors.blue,
              tabs: [Tab(text: 'List 1'), Tab(text: 'List 2')],
            ),
            Expanded(
              child: TabBarView(
                controller: tabController,
                children: [
                  PullToRefreshNotification(
                    color: Colors.blue,
                    maxDragOffset: 100.0,
                    onRefresh: () async {
                      await Future.delayed(Duration(seconds: 2));
                      setState(() {
                        itemCount += 10;
                        lastRefreshTime = DateTime.now();
                      });
                      return true;
                    },
                    child: CustomScrollView(
                      physics: ClampingScrollPhysics(),
                      slivers: [
                        SliverList(
                          delegate: SliverChildBuilderDelegate(
                            (context, index) {
                              return ListTile(
                                title: Text('Item $index'),
                                subtitle: Text('Last refresh: $lastRefreshTime'),
                              );
                            },
                            childCount: itemCount,
                          ),
                        ),
                      ],
                    ),
                  ),
                  ListView.builder(
                    key: PageStorageKey<String>('List2'),
                    itemCount: 50,
                    itemBuilder: (context, index) {
                      return ListTile(title: Text('Item $index'));
                    },
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }

  @override
  void dispose() {
    tabController.dispose();
    super.dispose();
  }
}

```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.