/** This interface may be used by the controller to create a class
 * that listens to the button presses of the unnassigned button on the
 * MonitorViewerPanel.  When the controller uses the setActionButton
 * method of the MonitorViewerPanel, it gives it an instance of this
 * interface.  That instance both establishes the text of the button
 * and is registered to receive notifications of when the button is
 * pressed
 * @author Anthony L. Slade */
public interface ButtonListener {
  /** The MonitorViewerPanel class uses this method to determine the
   * text of the action button on the bottom of the panel.
   * @return the text to display in the button */
  public String getActionString();
  /** The ButtonListener registered with the MonitorViewerPanel will
   * be notified of button presses through this method.
   * @param buttonCommand the text of the button pressed. */
  public void buttonPressed(String buttonCommand);
} // end interface ButtonListener