Dart offers some handy operators for dealing with values that might be null. One is the ??= assignment operator, which assigns a value to a variable only if that variable is currently null: int a; // The initial value of a is null.
Read moreWhat does a question mark after a variable mean?
The question mark in JavaScript is commonly used as conditional operator — called ternary operator when used with a colon (:) and a question mark (?) — to assign a variable name conditionally .
Read moreCan be null Dart?
The Dart language now supports sound null safety ! When you opt into null safety, types in your code are non-nullable by default, meaning that variables can’t contain null unless you say they can. With null safety, your runtime null-dereference errors turn into edit-time analysis errors.
Read moreWhat is string interpolation in Dart?
String interpolation is the process of inserting variable values into placeholders in a string literal . To concatenate strings in Dart, we can utilize string interpolation. We use the ${} symbol to implement string interpolation in your code.
Read moreWhat does after a variable mean in Dart?
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
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