flutter: NoSuchMethodError: The getter 'isEmpty' was called on null

Question

I am calling web API and receiving the Profile model as a response. When I am using the below code then it is throwing me an error:

try{
   if(profile.message.isEmpty){
      Navigator.of(context).pushNamed("/home");
   }else if(profile == null){
      _showDialog("Please check your internet connection");
   }else{
      _showDialog("Please enter valid credentials");
   }
}catch(exception){
   print(exception);
}

That's because `profile.message` returns `null`. You might want `if(profile?.message?.isEmpty ?? true)` — Günter Zöchbauer, Dec 14 '18 at 10:24

score 25 · Accepted Answer · edited Dec 14 '18 at 12:43

25

That is because profile.message returns null. You might want

if(profile?.message?.isEmpty ?? true)

? prevents an error if the previous part of the expression results in null and ?? true results in true if the previous part of the expression is null and therefore treats == null and isEmpty the same for the if(...) check.

edited Dec 14 '18 at 12:43

answered Dec 14 '18 at 10:30

Günter Zöchbauer

623,577
216
2,003
1,567

flutter: NoSuchMethodError: The getter 'isEmpty' was called on null

1 Answers1

Linked