import 'package:flutter/material.dart'; class SearchLoadingWidget extends StatelessWidget { final bool isLoading; SearchLoadingWidget(this.isLoading); @override Widget build(BuildContext context) { return new AnimatedOpacity( duration: new Duration(milliseconds: 300), opacity: isLoading ? 1.0 : 0.0, child: new Container( alignment: FractionalOffset.center, child: new CircularProgressIndicator(), ), ); } }