Brain Fog

Hi, I am having a bit of a problem with some simple java code. I'll just get on with showing you the code and explaining my problem.

import javax.swing.*;
 import java.awt.*;
 import java.awt.event.*;
 
  // Driver class
  public class Practice
  {
        public static void main(String[] args) 
        {
            Interpolation f = new Interpolation();
            f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            f.setVisible(true);
        }
    }
    
    // Frame class
 class Interpolation extends JFrame 
 {
      public Interpolation() 
      {
       super("Scrollbar Test");
       setSize(150,200);
       SamplePanel panel = new SamplePanel();
       getContentPane().add(panel);       
      }
  
 }

//Panel Class
 class SamplePanel extends JPanel
 {
     private int maxRange = 10;
     int a = 6;
     int b = 36;
 
     private Label redLabel =   new Label("Slider value= 0", Label.CENTER);
     private Label calcLabel =   new Label("New value = 0", Label.CENTER);
     private Label xLabel =   new Label("X", Label.CENTER);
     private Label yLabel =   new Label("Y", Label.CENTER);
     private Scrollbar redBar = new Scrollbar(Scrollbar.HORIZONTAL, 0, 1, 0, maxRange);
      
     public SamplePanel() 
     {
         setBackground(new Color(128, 128, 128));
         setLayout(new GridLayout(5, 1));

// Create scrollbar listener
         ScrollbarListener listener = new ScrollbarListener();
 
         // Add scrollbar and label to frame; attach
         // listener to scrollbar
         add(redBar);
         redBar.addAdjustmentListener(listener);
         add(redLabel);
         add(calcLabel);
         add(xLabel);
         add(yLabel);
    
     }  
    
 
      // Listener for all scrollbars
     private class ScrollbarListener implements AdjustmentListener 
     {
         public void adjustmentValueChanged(AdjustmentEvent evt) 
         {         
             int sliderValue = redBar.getValue();
             redLabel.setText("Slider value is currently = " + sliderValue);
                          
             int calcValue = a + (((a-b)/maxRange)*sliderValue);
             a = calcValue;
             calcLabel.setText("New Value = " + calcValue);
            
             
         }
     }    
}

Basically as I move the scrollbar(range: 1-10) I want to add the interval to the int a. The interval is calculated defined by 'calcValue'

My problem is that I want to assign 'calcValue' to a. As the scrollbar goes up this should contiually increase.

Hope I've explained this ok, if not please let me know and I will try and explain again.

Thanks

Sorted it now.

The correction was

a += calcValue;

(if anybody was interested)