text: class t_eq2_view{
  
      events;
  
      constructor(){
          document.getElementById("id_button").addEventListener("click",this.on_solve_click.bind(this));
      }
  
      set_events_list(events){
          this.events = events;
      }
  
      on_solve_click(){
          this.events.call_event("solve_clicked_uab");
      }
  
      get_a(){
          return document.getElementById("id_a").value;
      }
  
      get_b(){
          return document.getElementById("id_b").value;
      }
  
      get_c(){
          return document.getElementById("id_c").value;
      }
  
      set_solutions_para(solutions){
          document.getElementById("id_x1").innerHTML = "x1 = "+ solutions.x1_re + "+" + solutions.x1_im + "i";
          document.getElementById("id_x2").innerHTML = "x2 = "+ solutions.x2_re + "+" + solutions.x2_im + "i";
      }
  }