firebase - A value of type 'Future<String>' can't be assigned to a variable of type 'String'

Question

I have this code where am supposed to upload an image and get the downloaded url but whenever i do that I get this error

my url is String url;. So please why is this not working as it is supposed to

PS I checked other website to learn how to properly upload but it keeps giving me an error or is there a better way to do this.

My code image

Answer 1

uploadTask.whenComplete(()async{
url = await refs.getDownLoadURL();
....
});

Since it returns a Future you need to wait for it to be accessed