My condition doesnt work apprpraite in flutter for string

I have a list that stored by sqflite in flutter app, when i open the page i run this code in initState method to produce elements :

  String _val_s_list=values_list_r.map((e) => e!=null ? e.s_redio_q : ' ').toString();
  print("val_s_list: $_val_s_list");   printed: ///val_s_list: (1)

  ///method to return a string
  choosen_radio_s(_val_s_list);
  

out of init state defined method as below:

String val_s;
String choosen_radio_s(_val_s_list){
  setState(() {
    if(_val_s_list=="1"){
    return val_p1="1";
   }
   else{
     return val_p1="2";
   }
 });
}
///print: val_s: 2

but i can not understand why this is not currect on first condition and always returns val_p1="2", could some one help me about it??