PageController(viewportFraction: ....)

[name27]

viewportFraction: 0.7

double형으로 0~1 사이의 값을 가지며 1에 가까울수록 페이지 전체를 차지

import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}
class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    var pageController = PageController(viewportFraction: 0.7);
    return MaterialApp(
      home: Scaffold(
        body: DefaultTextStyle(
          style: TextStyle(fontSize: 36, color: Colors.black),
          child: SafeArea(
            child: PageView(
              controller: pageController,
              onPageChanged: ((v) {
                print(v);
              }),
              children: [
                Text('A페이지'),
                Text('B페이지'),
                Text('C페이지')
              ],
            ),
          ),
        ),
        floatingActionButton: FloatingActionButton(
          onPressed: (){
            pageController.previousPage(duration: Duration(seconds: 2), curve: Curves.easeIn);
          },
          child: Icon(Icons.navigate_next),
        ),
      ),
    );
  }
}