检查PageView - Flutter中是否有过卷

import 'package:flutter/material.dart';

class MyPageView extends StatefulWidget {
  @override
  _MyPageViewState createState() => _MyPageViewState();
}

class _MyPageViewState extends State<MyPageView> {
  PageController _pageController;
  bool _isScrolledToEnd = false;

  @override
  void initState() {
    super.initState();
    _pageController = PageController();
    _pageController.addListener(_scrollListener);
  }

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

  void _scrollListener() {
    if (_pageController.position.pixels == _pageController.position.maxScrollExtent) {
      setState(() {
        _isScrolledToEnd = true;
      });
    } else {
      setState(() {
        _isScrolledToEnd = false;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('PageView Scroll Check'),
      ),
      body: PageView(
        controller: _pageController,
        children: [
          // 页面1
          Container(
            color: Colors.blue,
            child: Center(
              child: Text(
                'Page 1',
                style: TextStyle(fontSize: 24, color: Colors.white),
              ),
            ),
          ),
          // 页面2
          Container(
            color: Colors.green,
            child: Center(
              child: Text(
                'Page 2',
                style: TextStyle(fontSize: 24, color: Colors.white),
              ),
            ),
          ),
          // 页面3
          Container(
            color: Colors.orange,
            child: Center(
              child: Text(
                'Page 3',
                style: TextStyle(fontSize: 24, color: Colors.white),
              ),
            ),
          ),
        ],
      ),
      bottomNavigationBar: BottomAppBar(
        child: Container(
          height: 50,
          child: Center(
            child: Text(
              _isScrolledToEnd ? '已滚动到最后一页' : '尚未滚动到最后一页',
              style: TextStyle(fontSize: 18),
            ),
          ),
        ),
      ),
    );
  }
}