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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 'dart:async';
import 'dart:ui';
import 'package:flutter/material.dart';
import 'picture_cache.dart';
class ClipperCachePage extends StatefulWidget {
const ClipperCachePage({super.key});
@override
State<ClipperCachePage> createState() => _ClipperCachePageState();
}
class _ClipperCachePageState extends State<ClipperCachePage>
with TickerProviderStateMixin {
final double _animateOffset = 100;
final ScrollController _controller = ScrollController();
final bool _isComplex = true;
late double _topMargin;
@override
void initState() {
super.initState();
_controller.addListener(() {
if (_controller.offset < 10) {
_controller.animateTo(_animateOffset, duration: const Duration(milliseconds: 1000), curve: Curves.ease);
} else if (_controller.offset > _animateOffset - 10) {
_controller.animateTo(0, duration: const Duration(milliseconds: 1000), curve: Curves.ease);
}
});
Timer(const Duration(milliseconds: 500), () {
_controller.animateTo(_animateOffset, duration: const Duration(milliseconds: 1000), curve: Curves.ease);
});
}
@override
void didChangeDependencies() {
super.didChangeDependencies();
const double itemHeight = 140;
final FlutterView view = View.of(context);
_topMargin = (view.physicalSize.height / view.devicePixelRatio - itemHeight * 3) / 2;
if (_topMargin < 0) {
_topMargin = 0;
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: Colors.blue,
body: ListView(
controller: _controller,
children: <Widget>[
SizedBox(height: _topMargin),
ClipPath(
clipBehavior: Clip.antiAliasWithSaveLayer,
child: _makeChild(0, _isComplex)
),
ClipRect(
clipBehavior: Clip.antiAliasWithSaveLayer,
child: _makeChild(1, _isComplex)
),
ClipRRect(
clipBehavior: Clip.antiAliasWithSaveLayer,
child: _makeChild(2, _isComplex)
),
const SizedBox(height: 1000),
],
),
);
}
Widget _makeChild(int itemIndex, bool complex) {
final BoxDecoration decoration = BoxDecoration(
color: Colors.white70,
boxShadow: const <BoxShadow>[
BoxShadow(
blurRadius: 5.0,
),
],
borderRadius: BorderRadius.circular(5.0),
);
return RepaintBoundary(
child: Container(
margin: const EdgeInsets.fromLTRB(10, 5, 10, 5),
decoration: complex ? decoration : null,
child: ListItem(index: itemIndex),
),
);
}
@override
void dispose() {
_controller.dispose();
super.dispose();
}
}