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 does variable mean in Dart?
Advertisements. A variable is “a named space in the memory” that stores values . In other words, it acts a container for values in a program. Variable names are called identifiers.
Read moreWhat is late variable in Flutter?
the late modifier is part of the new null-safety by dart it’s used to tell the compiler to treat this variable as non-nullable and will be initialized later without it the compiler will treat the variable as nullable and give error.
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