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// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'package:flutter/material.dart';
class CardModel {
CardModel(this.value, this.size, this.color);
int value;
Size size;
Color color;
String get label => 'Card $value';
Key get key => ObjectKey(this);
}
class PageViewApp extends StatefulWidget {
const PageViewApp({super.key});
@override
PageViewAppState createState() => PageViewAppState();
}
class PageViewAppState extends State<PageViewApp> {
@override
void initState() {
super.initState();
const List<Size> cardSizes = <Size>[
Size(100.0, 300.0),
Size(300.0, 100.0),
Size(200.0, 400.0),
Size(400.0, 400.0),
Size(300.0, 400.0),
];
cardModels = List<CardModel>.generate(cardSizes.length, (int i) {
final Color? color = Color.lerp(Colors.red.shade300, Colors.blue.shade900, i / cardSizes.length);
return CardModel(i, cardSizes[i], color!);
});
}
static const TextStyle cardLabelStyle =
TextStyle(color: Colors.white, fontSize: 18.0, fontWeight: FontWeight.bold);
List<CardModel> cardModels = <CardModel>[];
Size pageSize = const Size(200.0, 200.0);
Axis scrollDirection = Axis.horizontal;
bool itemsWrap = false;
Widget buildCard(CardModel cardModel) {
final Widget card = Card(
color: cardModel.color,
child: Container(
width: cardModel.size.width,
height: cardModel.size.height,
padding: const EdgeInsets.all(8.0),
child: Center(child: Text(cardModel.label, style: cardLabelStyle)),
),
);
final BoxConstraints constraints = (scrollDirection == Axis.vertical)
? BoxConstraints.tightFor(height: pageSize.height)
: BoxConstraints.tightFor(width: pageSize.width);
return Container(
key: cardModel.key,
constraints: constraints,
child: Center(child: card),
);
}
void switchScrollDirection() {
setState(() {
scrollDirection = (scrollDirection == Axis.vertical)
? Axis.horizontal
: Axis.vertical;
});
}
void toggleItemsWrap() {
setState(() {
itemsWrap = !itemsWrap;
});
}
Widget _buildDrawer() {
return Drawer(
child: ListView(
children: <Widget>[
const DrawerHeader(child: Center(child: Text('Options'))),
ListTile(
leading: const Icon(Icons.more_horiz),
selected: scrollDirection == Axis.horizontal,
trailing: const Text('Horizontal Layout'),
onTap: switchScrollDirection,
),
ListTile(
leading: const Icon(Icons.more_vert),
selected: scrollDirection == Axis.vertical,
trailing: const Text('Vertical Layout'),
onTap: switchScrollDirection,
),
ListTile(
onTap: toggleItemsWrap,
title: const Text('Scrolling wraps around'),
// TODO(abarth): Actually make this checkbox change this value.
trailing: Checkbox(value: itemsWrap, onChanged: null),
),
],
),
);
}
AppBar _buildAppBar() {
return AppBar(
title: const Text('PageView'),
actions: <Widget>[
Text(scrollDirection == Axis.horizontal ? 'horizontal' : 'vertical'),
],
);
}
Widget _buildBody(BuildContext context) {
return PageView(
// TODO(abarth): itemsWrap: itemsWrap,
scrollDirection: scrollDirection,
children: cardModels.map<Widget>(buildCard).toList(),
);
}
@override
Widget build(BuildContext context) {
return IconTheme(
data: const IconThemeData(color: Colors.white),
child: Scaffold(
appBar: _buildAppBar(),
drawer: _buildDrawer(),
body: _buildBody(context),
),
);
}
}
void main() {
runApp(
const MaterialApp(
title: 'PageView',
home: PageViewApp(),
),
);
}