Taking multiple inputs from user in one box in MATLAB

I want to take multiple values with waitfor operator but my code does not work. Where is my mistake?

methods (Access = private)
        
    % Callback function
        
     function ButtonPushed(app, event)
                
     %Reading dataset and getting the inputs from user by using input operation

                
      matrix = xlsread("Transfusion.xlsx");
                
      attributesNum = size(matrix,2) - 1 ;
                
      X = zeros(attributesNum,1);
                
      for i=1:attributesNum
                    
          waitfor(app.firstVal, 'Value');
                        
          value = app.firstVal.Value;
                        
          X(i,1) = value;
                    
          %Update text of ValuesLabel (for demostrating the concept).
                        
          text = ['Values: ', sprintf('%.1f, ', X(1:i))];
                        
          app.ValuesLabel.Text = text(1:end-2);
                
       end

                
       %Display X in Command window for testing
                
       disp(X)
       
        ...
       end