Flutter – Rotate Transition

In Flutter, the page_transition package is used to create beautiful page transitions. It provides a wide range of effects that can be used from moving from one route to another. It is very convenient to use. In this article, we will explore the same by building a simple application.

To build a simple application depicting the use of page_transition package for a Rotate transition follow the below steps:

• Add page_transition to the dependencies in pubspec.yaml file
• Import the same dependency in the main.dart file
• Use a StatelessWidget to give a structure to the application
• Design the homepage
• Define the onGenerateRoute property in the MaterialApp widget to transition to form the home page

Now, let’s look in the steps in detail:

Adding the Dependency:

You can add the page_transition dependency to the pubspec.yaml file as follows:

Importing the Dependency:

To import the dependency to your main.dart file use the following:

import 'package:page_transition/page_transition.dart';

Designing the App Structure:

The StatelessWidget can be used to give a simple structure to the application that contains an appbar and a body for the content as shown below:

Dart

class MyApp extends StatelessWidget {

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      title: 'GeeksForGeeks',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
}

Designing the Homepage:

A StatelessWidget can also be used to design the Homepage for the app. A button will also be added to the homepage which will have a transition action attached to it when pressed as shown below:

Dart

class MyHomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.greenAccent,
      appBar: AppBar(
        title: Text('GeeksForGeeks'),
        backgroundColor: Colors.green,
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          crossAxisAlignment: CrossAxisAlignment.center,
          children: <Widget>[
            RaisedButton(
              child: Text('Rotate Transition Button'),
              onPressed: () {
                Navigator.push(
                  context,
                  PageTransition(
                    curve: Curves.bounceOut,
                    type: PageTransitionType.rotate,
                    alignment: Alignment.topCenter,
                    child: SecondPage(),
                  ),
                );
              },
            ),
          ],
        ),
      ),
    );
  }
}

Defining the OnRouteSetting property:

The onRouteSettings property is used to extract information from one page and send it to another page (or, route). We will assign the same property to the button action that we added in the homepage that will transition it to the second page as shown below:

Dart

onGenerateRoute: (settings) {
        switch (settings.name) {
          case '/second':
            return PageTransition(
              child: SecondPage(
              ),
              type: PageTransitionType.fade,
              settings: settings,
            );

Complete Source Code:

Dart

import 'package:flutter/material.dart';
import 'package:page_transition/page_transition.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // root of application
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      title: 'GeeksForGeeks',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(),
      onGenerateRoute: (settings) {
        switch (settings.name) {
          case '/second':
            return PageTransition(
              child: SecondPage(
              ),
              type: PageTransitionType.fade,
              settings: settings,
            );
            break;
          default:
            return null;
        }
      },
    );
  }
}

/// Homepage
class MyHomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.greenAccent,
      appBar: AppBar(
        title: Text('GeeksForGeeks'),
        backgroundColor: Colors.green,
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          crossAxisAlignment: CrossAxisAlignment.center,
          children: <Widget>[
            RaisedButton(
              child: Text('Rotate Transition Button'),
              onPressed: () {
                Navigator.push(
                  context,
                  PageTransition(
                    curve: Curves.bounceOut,
                    type: PageTransitionType.rotate,
                    alignment: Alignment.topCenter,
                    child: SecondPage(),
                  ),
                );
              },
            ),
          ],
        ),
      ),
    );
  }
}

//definition of second page
class SecondPage extends StatelessWidget {

  final String title;

  /// constructor of the page
  const SecondPage({Key key, this.title}) : super(key: key);
  @override
  Widget build(BuildContext context) {
    final args = ModalRoute.of(context).settings.arguments;
    return Scaffold(
      appBar: AppBar(
        title: Text(args ?? "Page Transition Plugin"),
      ),
      body: Center(
        child: Text('Second Page'),
      ),
    );
  }
}

Output: