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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.
// See //dev/devicelab/bin/tasks/flutter_gallery__image_cache_memory.dart
import 'dart:async';
import 'package:flutter/widgets.dart';
import 'package:flutter/scheduler.dart';
import 'package:flutter_test/flutter_test.dart';
// Once we provide an option for images to be resized to
// fit the container, we should see a significant drop in
// the amount of memory consumed by this benchmark.
Future<void> main() async {
const int numItems = 10;
runApp(Directionality(
textDirection: TextDirection.ltr,
child: ListView.builder(
key: const Key('ImageList'),
itemCount: numItems,
itemBuilder: (BuildContext context, int position) {
return Container(
width: 200,
height: 200,
child: Center(
child: Image.asset(
'monochrome/red-square-1024x1024.png',
package: 'flutter_gallery_assets',
width: 100,
height: 100,
fit: BoxFit.contain,
key: Key('image_$position'),
),
),
);
},
),
));
await SchedulerBinding.instance.endOfFrame;
// We are waiting for the GPU to rasterize a frame here. This makes this flaky,
// we can rely on a more deterministic such as `Window.onReportTimings` once
// https://github.com/flutter/flutter/issues/26154 is addressed.
await Future<void>.delayed(const Duration(milliseconds: 50));
debugPrint('==== MEMORY BENCHMARK ==== READY ====');
final WidgetController controller =
LiveWidgetController(WidgetsBinding.instance);
debugPrint('Scrolling...');
final Finder list = find.byKey(const Key('ImageList'));
final Finder lastItem = find.byKey(const Key('image_${numItems - 1}'));
do {
await controller.drag(list, const Offset(0.0, -30.0));
await Future<void>.delayed(const Duration(milliseconds: 20));
} while (!lastItem.precache());
debugPrint('==== MEMORY BENCHMARK ==== DONE ====');
}