Answer (1) A nullable type by adding a question mark (?) after the type name. For example, a variable _contacts? can contain a value, or it can be null. Answer (2) It is called “Null-aware operators”.
Read moreWhat does the question mark mean in flutter?
This is with null safety, the question mark means that this String? can possibly be null and flutter will allow you to assign null to it . String can never be null and you’ll get an error before compiling.29 Mar 2021
Read moreWhat does the question mark mean in flutter?
This is with null safety, the question mark means that this String? can possibly be null and flutter will allow you to assign null to it . String can never be null and you’ll get an error before compiling.29 Mar 2021
Read moreWhat are two question marks flutter?
double question mark operator means “if null “.
Read moreWhat is late final in flutter?
Late final variables Unlike normal final fields, you do not have to initialize the field in its declaration or in the constructor initialization list . You can assign to it later at runtime. But you can only assign to it once, and that fact is checked at runtime.
Read moreWhat does Late mean flutter?
Lets get lazy… late has another great application for your Flutter code: you can remove many of your initState / constructor calls! This is because late runs “lazily” , which means it is not run at all until it is referenced the first time.
Read moreWhat is late variable in Dart?
The late keyword By declaring a non-nullable late variable, we promise that it will be non-null at runtime, and Dart helps us with some compile-time guarantees.
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