// 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';classHeavyGridViewPageextendsStatelessWidget{@overrideWidgetbuild(BuildContextcontext){returnGridView.builder(itemCount:1000,gridDelegate:constSliverGridDelegateWithFixedCrossAxisCount(crossAxisCount:3),itemBuilder:(BuildContextcontext,intindex)=>HeavyWidget(index),).build(context);}}classHeavyWidgetextendsStatelessWidget{HeavyWidget(this.index):super(key:ValueKey<int>(index));finalintindex;finalList<int>_weight=List<int>(1000000);@overrideWidgetbuild(BuildContextcontext){returnSizedBox(width:200,height:200,child:Text('$index: ${_weight.length}'),);}}