Flutter – Animated ScrollView

Creating an animated scroll view in Flutter involves using a combination of widgets and animation controllers to achieve the desired scrolling effect. Here we use Tween Animation to implement animation. In this article we are going to add an animation effect to a ScrollView A sample video is given below to get an idea about what we are going to do in this article.

Basic Syntax of Creating an Animation in Flutter

// Create an AnimationController with a 4-second duration
_animationController = AnimationController(
      vsync: this, // Associate the AnimationController with the widget's lifecycle
      duration: Duration(seconds: 4),
    );
    // Create a linear Tween animation from 0 to 1
    _animation = Tween<double>(begin: 0, end: 1).animate(_animationController);
    // Trigger the animation when the widget is first built
    _animationController.forward();

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(
      // Define the app's theme
      theme: ThemeData(
        primarySwatch: Colors.green, // Set the app's primary theme color
      ),
      debugShowCheckedModeBanner: false,
      home: AnimatedScrollViewDemo(),
    );
  }
}

Step 5: Create AnimatedScrollViewDemo Class

In this class we are going to create a ListView then add some animation to the Scrolling effect. Comments are added for better understanding.

Dart

class AnimatedScrollViewDemo extends StatefulWidget {
  @override
  _AnimatedScrollViewDemoState createState() => _AnimatedScrollViewDemoState();
}

// Create the main state class
class _AnimatedScrollViewDemoState extends State<AnimatedScrollViewDemo> {
  // Create a list of 50 items with "Item 0", "Item 1", etc.
  final List<String> items = List.generate(50, (index) => 'Item $index');

  // Create a ScrollController to
  // manage the ListView's scroll position
  ScrollController _controller = ScrollController();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Animated Scroll View Demo'),
      ),
      body: ListView.builder(
        controller:
            _controller, // Associate the ScrollController with the ListView
        itemCount: items.length,
        itemBuilder: (context, index) {
          return AnimatedItemWidget(
            index: index,
            item: items[index],
          );
        },
      ),
    );
  }
}

Step 6: Create AnimatedItemWidget Class

In this class we going to Create a widget to represent an individual item with animations. Comments are added for better understanding of the code.

Dart

// Create a widget to represent an individual
// item with animations
class AnimatedItemWidget extends StatefulWidget {
  final int index;
  final String item;

  AnimatedItemWidget({required this.index, required this.item});

  @override
  _AnimatedItemWidgetState createState() => _AnimatedItemWidgetState();
}

// Create the state for an individual item
class _AnimatedItemWidgetState extends State<AnimatedItemWidget>
    with SingleTickerProviderStateMixin {

  // Define an AnimationController for controlling animations
  late AnimationController _animationController;

  // Define an Animation to interpolate
  // values between 0 and 1
  late Animation<double> _animation;

  @override
  void initState() {
    super.initState();

    // Create an AnimationController with a 4-second duration
    _animationController = AnimationController(
      vsync:
          this, // Associate the AnimationController
                  // with the widget's lifecycle
      duration: Duration(seconds: 4),
    );

    // Create a linear Tween animation from 0 to 1
    _animation = Tween<double>(begin: 0, end: 1).animate(_animationController);

    // Trigger the animation when the widget is first built
    _animationController.forward();
  }

  @override
  Widget build(BuildContext context) {
    return FadeTransition(
      opacity: _animation,
      child: Card(
        elevation: 2,
        margin: EdgeInsets.all(8),
        child: ListTile(
          title: Text(widget.item),
        ),
      ),
    );
  }

  @override
  void dispose() {
    // Dispose of the AnimationController
    // to free resources
    _animationController.dispose();
    super.dispose();
  }
}

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(
      // Define the app's theme
      theme: ThemeData(
        // Set the app's primary theme color
        primarySwatch: Colors.green,
      ),
      debugShowCheckedModeBanner: false,
      home: AnimatedScrollViewDemo(),
    );
  }
}


class AnimatedScrollViewDemo extends StatefulWidget {
  @override
  _AnimatedScrollViewDemoState createState() => _AnimatedScrollViewDemoState();
}

// Create the main state class
class _AnimatedScrollViewDemoState extends State<AnimatedScrollViewDemo> {

  // Create a list of 50 items with "Item 0", "Item 1", etc.
  final List<String> items = List.generate(50, (index) => 'Item $index');

  // Create a ScrollController to manage the ListView's scroll position
  ScrollController _controller = ScrollController();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Animated Scroll View Demo'),
      ),
      body: ListView.builder(
        controller:
            _controller, // Associate the ScrollController with the ListView
        itemCount: items.length,
        itemBuilder: (context, index) {
          return AnimatedItemWidget(
            index: index,
            item: items[index],
          );
        },
      ),
    );
  }
}

// Create a widget to represent an individual item with animations
class AnimatedItemWidget extends StatefulWidget {
  final int index;
  final String item;

  AnimatedItemWidget({required this.index, required this.item});

  @override
  _AnimatedItemWidgetState createState() => _AnimatedItemWidgetState();
}

// Create the state for an individual item
class _AnimatedItemWidgetState extends State<AnimatedItemWidget>
    with SingleTickerProviderStateMixin {
  // Define an AnimationController for controlling animations
  late AnimationController _animationController;

  // Define an Animation to interpolate values between 0 and 1
  late Animation<double> _animation;

  @override
  void initState() {
    super.initState();

    // Create an AnimationController with a 4-second duration
    _animationController = AnimationController(
      vsync:
          this, // Associate the AnimationController with the widget's lifecycle
      duration: Duration(seconds: 4),
    );

    // Create a linear Tween animation from 0 to 1
    _animation = Tween<double>(begin: 0, end: 1).animate(_animationController);

    // Trigger the animation when the widget is first built
    _animationController.forward();
  }

  @override
  Widget build(BuildContext context) {
    return FadeTransition(
      opacity: _animation,
      child: Card(
        elevation: 2,
        margin: EdgeInsets.all(8),
        child: ListTile(
          title: Text(widget.item),
        ),
      ),
    );
  }

  @override
  void dispose() {
    // Dispose of the AnimationController to free resources
    _animationController.dispose();
    super.dispose();
  }
}

Output: