Flutter Question mark dot

“!” is a new dart operator for conversion from a nullable to a non-nullable type . Read here and here about sound null safety. Use it only if you are absolutely sure that the value will never be null and do not confuse it with the conditional property access operator. Follow this answer to receive notifications.

Null-aware operators are used in almost every programming language to check whether the given variable value is Null. The keyword for Null in the programming language Dart is null. Null means a variable which has no values assign ever and the variable is initialized with nothing like.

If double question marks are uses it is to emphasise something in return, usually from the shock of the previous thing said . For example, if I said: ‘My dog just died’ (sad, but used for example…) Someone may reply.