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 moreHow do you access static variables in Flutter?
There is no need to create a class object to access a static variable or call a static method: simply put the class name before the static variable or method name to use them .
Read moreHow do you use variable globally in Flutter?
7 Answers. 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 put a variable in a String Flutter?
If you are attempting to put a String variable inside another static String you can do the following for simple variables: String firstString = ‘sentence’; String secondString = ‘This is a $firstString’; Which will output This is a sentence .
Read moreWhat is dynamic variable in Flutter?
When defined with an initial value, var is int in this case. dynamic: can change TYPE of the variable, & can change VALUE of the variable later in code . var: can’t change TYPE of the variable, but can change the VALUE of the variable later in code.
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