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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 'package:flutter/material.dart';
/// Displays a new (from image cache's perspective) large image every 500ms.
class LargeImageChangerPage extends StatefulWidget {
const LargeImageChangerPage({super.key});
@override
State<LargeImageChangerPage> createState() => _LargeImageChangerState();
}
class _LargeImageChangerState extends State<LargeImageChangerPage> {
Timer? _timer;
int imageIndex = 0;
late ImageProvider currentImage;
@override
void didChangeDependencies() {
super.didChangeDependencies();
currentImage = ResizeImage(
const ExactAssetImage('assets/999x1000.png'),
width: (MediaQuery.of(context).size.width * 2).toInt() + imageIndex,
height: (MediaQuery.of(context).size.height * 2).toInt() + imageIndex,
allowUpscaling: true,
);
_timer?.cancel();
_timer = Timer.periodic(const Duration(seconds: 3), (Timer timer) {
currentImage.evict().then((_) {
setState(() {
imageIndex = (imageIndex + 1) % 6;
currentImage = ResizeImage(
const ExactAssetImage('assets/999x1000.png'),
width: (MediaQuery.of(context).size.width * 2).toInt() + imageIndex,
height: (MediaQuery.of(context).size.height * 2).toInt() + imageIndex,
allowUpscaling: true,
);
});
});
});
}
@override
void dispose() {
_timer?.cancel();
super.dispose();
}
@override
Widget build(BuildContext context) {
return Image(image: currentImage);
}
}