Flutter – Custom Scroll View

A CustomScrollView in Flutter is a highly customizable scrolling widget that allows you to create complex scrolling effects and layouts. You can use it to create scrollable views with multiple slivers, each having its own behavior. In this article, we are going to implement the CustomScrollView widget. A sample video is given below to get an idea about what we are going to do in this article.

Basic Syntax of CustomScrollView Widget

CustomScrollView(
  slivers: <Widget>[
    // List of sliver widgets
    SliverWidget1(
      // Sliver widget properties
    ),
    SliverWidget2(
      // Sliver widget properties
    ),
    // ... More sliver widgets ...
  ],
)

Required Tools

To build this app, you need the following items installed on your machine:

• Visual Studio Code / Android Studio
• Android Emulator / iOS Simulator / Physical Device device.
• Flutter Installed
• Flutter plugin for VS Code / Android Studio.

Step By Step Implementation

Step 1: Create a New Project in Android Studio

To set up Flutter Development on Android Studio please refer to Android Studio Setup for Flutter Development, and then create a new project in Android Studio please refer to Creating a Simple Application in Flutter.

Step 2: Import the Package

First of all import material.dart file.

import 'package:flutter/material.dart';

Step 3: Execute the main Method

Here the execution of our app starts.

Dart

void main() {
  runApp(MyApp());
}

Step 4: Create MyApp Class

In this class we are going to implement the MaterialApp , here we are also set the Theme of our App.

Dart

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData(
        primarySwatch: Colors.green, // Set the app's primary theme color
      ),
      debugShowCheckedModeBanner: false,
      title: 'CustomScrollView Example',
      home: CustomScrollViewExample(),
    );
  }
}

Step 5: Create CustomScrollViewExample Class

In this class we are going to Implement the CustomScrollView with a SliverAppBar that has an expandable image background and a SliverList containing a list of items. Comments are added for better understanding.

CustomScrollView(
        slivers: <Widget>[
          // SliverAppBar
          SliverAppBar(
            expandedHeight: 200.0,
            floating: false,
            pinned: true,
            flexibleSpace: FlexibleSpaceBar(
              title: Text(
                'CustomScrollView', // Title text for the SliverAppBar
                style: TextStyle(color: Colors.black, fontSize: 15),
              ),
              background: Image.network(
                'https://static.startuptalky.com/2021/06/GeeksforGeeks-StartupTalky.jpg', // Replace with your image URL
                fit: BoxFit.cover, // Ensure the image covers the entire space
              ),
            ),
          ),
          // SliverList
          SliverList(
            delegate: SliverChildBuilderDelegate(
              (BuildContext context, int index) {
                return ListTile(
                  title: Text('Item $index'), // Display list item with index
                );
              },
              childCount: 50, // Number of list items
            ),
          ),
        ],
      ),

Dart

class CustomScrollViewExample extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('CustomScrollView Example'),
      ),
      body: CustomScrollView(
        slivers: <Widget>[
          // SliverAppBar
          SliverAppBar(
            expandedHeight: 200.0,
            floating: false,
            pinned: true,
            flexibleSpace: FlexibleSpaceBar(
              title: Text(
                'CustomScrollView', // Title text for the SliverAppBar
                style: TextStyle(color: Colors.black, fontSize: 15),
              ),
              background: Image.network(
                'https://static.startuptalky.com/2021/06/GeeksforGeeks-StartupTalky.jpg', // Replace with your image URL
                fit: BoxFit.cover, // Ensure the image covers the entire space
              ),
            ),
          ),
          // SliverList
          SliverList(
            delegate: SliverChildBuilderDelegate(
              (BuildContext context, int index) {
                return ListTile(
                  title: Text('Item $index'), // Display list item with index
                );
              },
              childCount: 50, // Number of list items
            ),
          ),
        ],
      ),
    );
  }
}

Here is the full Code of main.dart file

Dart

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData(
        primarySwatch: Colors.green, // Set the app's primary theme color
      ),
      debugShowCheckedModeBanner: false,
      title: 'CustomScrollView Example',
      home: CustomScrollViewExample(),
    );
  }
}

class CustomScrollViewExample extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('CustomScrollView Example'),
      ),
      body: CustomScrollView(
        slivers: <Widget>[
          // SliverAppBar
          SliverAppBar(
            expandedHeight: 200.0,
            floating: false,
            pinned: true,
            flexibleSpace: FlexibleSpaceBar(
              title: Text(
                'CustomScrollView', // Title text for the SliverAppBar
                style: TextStyle(color: Colors.black, fontSize: 15),
              ),
              background: Image.network(
                'https://static.startuptalky.com/2021/06/GeeksforGeeks-StartupTalky.jpg', // Replace with your image URL
                fit: BoxFit.cover, // Ensure the image covers the entire space
              ),
            ),
          ),
          // SliverList
          SliverList(
            delegate: SliverChildBuilderDelegate(
              (BuildContext context, int index) {
                return ListTile(
                  title: Text('Item $index'), // Display list item with index
                );
              },
              childCount: 50, // Number of list items
            ),
          ),
        ],
      ),
    );
  }
}

Output: