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’ .
Read moreHow do you use global variables in darts?
Show activity on this post. Just create a library file and create fields for globals you need there. Import this library everywhere you need access to these fields. create a singleton in the globals library (see How do you build a Singleton in Dart? for more details).
Read moreHow do you know what variable you are in Dart?
Dart objects have runtimeType property which returns Type . To check whether the object has a certain type, use == operator . Unlike is , it will only return true if compared to an exectly same type, which means comparing it with its super class will return false .
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 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)
Read moreWhat is the operator in Dart?
The operators are special symbols that are used to carry out certain operations on the operands . The Dart has numerous built-in operators which can be used to carry out different functions, for example, ‘+’ is used to add two operands. Operators are meant to carry operations on one or two operands.
Read moreWhat is the double question mark operator?
The double question mark operator is called the nullish coalescing operator, and it’s a new feature of JavaScript ES2020 that allows you provide a default value to use when a variable expression evaluates to null or undefined .
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