double question mark operator means “if null “. Take the following expression, for example. String a = b ?? ‘hello’; This means a equals b , but if b is null then a equals ‘hello’ .4 Oca 2019
Read moreWhat is final flutter?
“final” means single-assignment : a final variable or field must have an initializer. Once assigned a value, a final variable’s value cannot be changed. final modifies variables. “const” has a meaning that’s a bit more complex and subtle in Dart.
Read moreHow do you deal with null safety in flutter?
Null Safety in simple words means a variable cannot contain a ‘null’ value unless you initialized with null to that variable . With null safety, all the runtime null-dereference errors will now be shown in compile time. String name = null ; // This means the variable name has a null value.
Read moreHow do you check for null in flutter?
Checking Nulls and Null-Aware Operators in Dart
Read moreWhat are null-aware operators flutter?
Null-aware operators in dart allow you to make computations based on whether or not a value is null . It’s shorthand for longer expressions. A null-aware operator is a nice tool for making nullable types usable in Dart instead of throwing an error.28 Oca 2022
Read moreHow many null-aware operators flutter?
Anytime you can write less code without sacrificing readability, you probably should. The three null-aware operators that Dart provides are ?. , ?? , and ??= .
Read moreWhat does ~/ mean in Dart?
~/ Divide, returning an integer result . and ~/= integer division and assignment. There is not really an equivalent in Java. In Java the result is an integer if the result is assigned to an integer variable (not sure though, not a Java dev)
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