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// Copyright (c) 2016, the Flutter project authors. Please see the AUTHORS file
// for details. 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:ui' as ui;
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter/widgets.dart';
class ExampleApp extends StatefulComponent {
ExampleState createState() => new ExampleState();
}
const List<double> _ratios = const <double>[ 1.0, 1.8, 1.3, 2.4, 2.5, 2.6, 3.9 ];
class ExampleState extends State<ExampleApp> {
int _index = 0;
double _ratio = _ratios[0];
final EdgeDims padding = new EdgeDims.TRBL(
ui.window.padding.top,
ui.window.padding.right,
ui.window.padding.bottom,
ui.window.padding.left
);
void _handlePressed() {
setState(() {
_index++;
_index = _index % _ratios.length;
_ratio = _ratios[_index];
});
}
Widget build(BuildContext context) {
const double size = 200.0; // 200 logical pixels
TextStyle style = new TextStyle(color: const Color(0xFF0000000));
return new MediaQuery(
data: new MediaQueryData(
size: ui.window.size,
devicePixelRatio: _ratio,
padding: padding
),
child: new AssetVendor(
bundle: rootBundle,
devicePixelRatio: _ratio,
child: new Material(
child: new Padding(
padding: const EdgeDims.symmetric(vertical: 48.0),
child: new Column(
children: <Widget>[
new AssetImage(
name: 'assets/2.0x/starcircle.png',
height: size,
width: size,
fit: ImageFit.fill
),
new Text('Image designed for pixel ratio 2.0', style: style),
new AssetImage(
name: 'assets/starcircle.png',
height: size,
width: size,
fit: ImageFit.fill
),
new Text(
'Image variant for pixel ratio: ' + _ratio.toString(),
style: style
),
new RaisedButton(
child: new Text('Change pixel ratio', style: style),
onPressed: _handlePressed
)
],
justifyContent: FlexJustifyContent.spaceBetween
)
)
)
)
);
}
}
main() {
runApp(new ExampleApp());
}