[Flutter] delay 주기 (2가지 방법)

// example 1 
Future<bool> _getFutureBool() { 
	return Future.delayed(Duration(milliseconds: 500)) .then((onValue) => true); 
    }
 
 
 // example 2 
 print('1'); 
 Future.delayed(const Duration(milliseconds: 500), () { 
 	print('Hello, world'); 
 	});
 
 print('2');