本文实例为大家分享了flutter PageView左右滑动切换视图的具体代码,供大家参考,具体内容如下import dart:math ;import p
本文实例为大家分享了flutter PageView左右滑动切换视图的具体代码,供大家参考,具体内容如下
import 'dart:math'; import 'package:cached_network_image/cached_network_image.dart'; import 'package:flutter/cupertino.dart'; import 'package:flutter/material.dart'; import 'package:flutter_x/base/base_appbar_page.dart'; class LeftPageViewPage extends StatefulWidget { @override State<StatefulWidget> createState() { return new LeftPageViewPageState(); } } class LeftPageViewPageState extends BaseAppBarPageState<LeftPageViewPage> { @override String buildInitState() { buildBackBar("pageView", backIcon: Icons.arrow_back_ios); return null; } final _controller = new PageController(); static const _kDuration = const Duration(milliseconds: 300); static const _kCurve = Curves.ease; final List<Widget> _pages = <Widget>[ new ConstrainedBox( constraints: const BoxConstraints.expand(), child: new CachedNetworkImage( width: double.infinity, height: double.infinity, fit: BoxFit.fill, imageUrl: "http://b-ssl.duitang.com/uploads/item/201311/02/20131102150044_YGB5u.jpeg", placeholder: (context, url) => new SizedBox( width: 24.0, height: 24.0, child: new CircularProgressIndicator( strokeWidth: 2.0, ), ), errorWidget: (context, url, error) => new Icon(Icons.error), ), ), new ConstrainedBox( constraints: const BoxConstraints.expand(), child: new CachedNetworkImage( width: double.infinity, height: double.infinity, fit: BoxFit.fill, imageUrl: "http://b-ssl.duitang.com/uploads/item/201311/02/20131102150044_YGB5u.jpeg", placeholder: (context, url) => new SizedBox( width: 24.0, height: 24.0, child: new CircularProgressIndicator( strokeWidth: 2.0, ), ), errorWidget: (context, url, error) => new Icon(Icons.error), ), ), new ConstrainedBox( constraints: const BoxConstraints.expand(), child: new Stack( //Stack即层叠布局控件,能够将子控件层叠排列 //alignment:此参数决定如何去对齐没有定位(没有使用Positioned)或部分定位的子widget。所谓部分定位,在这里特指没有在某一个轴上定位:left、right为横轴,top、bottom为纵轴,只要包含某个轴上的一个定位属性就算在该轴上有定位。 alignment: AlignmentDirectional.topStart, children: <Widget>[ new CachedNetworkImage( width: double.infinity, height: double.infinity, fit: BoxFit.fill, imageUrl: "http://b-ssl.duitang.com/uploads/item/201311/02/20131102150044_YGB5u.jpeg", placeholder: (context, url) => SizedBox(width: 24,height: 25,child: CircularProgressIndicator(strokeWidth: 2.0,),), errorWidget: (context, url, error) => new Icon(Icons.error), ), new Align( alignment: Alignment.bottomCenter, child: new Container( margin: EdgeInsets.only(bottom: 80.0), child: FlatButton(onPressed: (){}, child: Text("立即体验")) , ), ), ], )), ]; @override Widget buildWidget(BuildContext context) { // TODO: implement buildWidget return new Stack( children: <Widget>[ //pageViw PageView.builder( physics: new AlwaysScrollableScrollPhysics(), controller: _controller, itemBuilder: (BuildContext context, int index) { return _pages[index]; }, //条目个数 itemCount: _pages.length, ), //圆点指示器 new Positioned( bottom: 0.0, left: 0.0, right: 0.0, child: new Container( color: Colors.white, padding: const EdgeInsets.all(20.0), child: new Center( child: new DotsIndicator( controller: _controller, itemCount: _pages.length, onPageSelected: (int page) { _controller.animateToPage( page, duration: _kDuration, curve: _kCurve, ); }), ), ), ), ], ); } } class DotsIndicator extends AnimatedWidget { DotsIndicator({ this.controller, this.itemCount, this.onPageSelected, this.color: Colors.red, }) : super(listenable: controller); /// The PageController that this DotsIndicator is representing. final PageController controller; /// The number of items managed by the PageController final int itemCount; /// Called when a dot is tapped final ValueChanged<int> onPageSelected; /// The color of the dots. /// /// Defaults to `Colors.white`. final Color color; // The base size of the dots static const double _kDotSize = 8.0; // The increase in the size of the selected dot static const double _kMaxZoom = 2.0; // The distance between the center of each dot static const double _kDotSpacing = 25.0; Widget _buildDot(int index) { double selectedness = Curves.easeOut.transform( max( 0.0, 1.0 - ((controller.page ?? controller.initialPage) - index).abs(), ), ); double zoom = 1.0 + (_kMaxZoom - 1.0) * selectedness; return new Container( width: _kDotSpacing, child: new Center( child: new Material( color: color, type: MaterialType.circle, child: new Container( width: _kDotSize * zoom, height: _kDotSize * zoom, child: new InkWell( onTap: () => onPageSelected(index), ), ), ), ), ); } Widget build(BuildContext context) { return new Row( mainAxisAlignment: MainAxisAlignment.center, children: new List<Widget>.generate(itemCount, _buildDot), ); } }
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持好代码网。