import java.awt.*;
import java.applet.Applet;

public class AdjustUpDown extends Applet
{
  Button upButton = new Button("Increment");
  Button downButton = new Button("Decrement");
  TextField delta = new TextField("1", 5);  // Width 5
  int counter = 0;
  
  public void init() {
    add(downButton);
    add(upButton);
    add(delta);
    repaint();
  }
  
  public void paint(Graphics g) {
    g.drawString("Count: "+counter, 70, 50);
  }
  
  public boolean action(Event e, Object o) { 
    // Might be an up or a down button click 
    // or "Return" on the text field
    
    // First, get the value in delta field, resetting if junk
    int deltaValue;
    deltaValue = getValue(delta);
    
    // Check the event's "target"
    if (e.target==downButton)
      counter = counter-deltaValue;
    else if (e.target==upButton)
      counter = counter+deltaValue;
    // If neither down nor up button, no special action
    
    repaint();
    return true;
  }
  
  // Next, an example of an extra function:
  // To obtain the number currently in a nominated text field
  // Resets the field to 1 if it contains junk (and result is 1)
  
  private int getValue(TextField tf) {
    String string;
    int value;
    string = tf.getText();
    try {
      value = Integer.parseInt(string);
    } catch (NumberFormatException ne) {  
      // Junk in field - reset it
      value = 1;
      tf.setText("1");
    }
    return value;
  }
  
}