How can a value be assigned to a variable of an extended class?

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Hello, I want set a value of extended class. How can i do it? Thanks.

Dart

 class A {
     String? value1A;    

   A({ 
    this.value1A, 
  });
}

class B extends A {

   String value1B = "";  

   value1A= ""; //<= I can't assing a value
 
}

What I have tried:

Dart

class B extends A {

   String value1B = "";
   

   value1A= "";
   super.value1A="";
   A newA; 
   newA.value1A= "";   
 
}

Posted 3-Mar-24 3:34am

gacar

Updated 3-Mar-24 3:53am

v2

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M-Badger · Accepted Answer · 2024-03-03T04:35:00

The issue with your code is that you're trying to assign a value to value1A directly in the class body of B. In Dart, you can’t assign values to inherited variables directly in the class body. You should do this inside a method or constructor.

Dart

class A {
  String? value1A;

  A({ 
    this.value1A, 
  });
}

class B extends A {
  String value1B = "";  

  B() {
    value1A = ""; // Now you can assign a value
  }
}