/*
 *  File:  ListDynTest.java
 *
 *  Create a scrolling List with multiple selections, using ListSelectionEvents
 *  for (singly) selected items.  Shows how the user can add and
 *  remove items (with TextFields).
 *
 *  Copyright:  Northeast Parallel Architectures Center
 *  
 */

import javax.swing.*;
import javax.swing.JComponent.*;
import java.awt.Color;
import java.awt.Toolkit;
import java.awt.Font;
import javax.swing.event.*;
import java.util.*;
import java.lang.*;
import java.awt.TextField;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;


public class ListDynTest extends JApplet
                      implements ListSelectionListener, ActionListener
{
  // Allow five visible items in the list, 
  //    and allow multiple selections:

  private JList wordList ;
  private JScrollPane scrollPane;
  
  private String resultstring;
  private JLabel resultlabel;

  private JLabel newlabel = new JLabel("Add an adjective:     ");
  private JTextField newitemtext = new JTextField (20);
  private JLabel oldlabel = new JLabel("      Remove one:     ");
  private JTextField olditemtext = new JTextField (20);
  
  private Font f = new Font ( "Dialog", Font.PLAIN, 18 );

  String words[] = {"Snowy","Cold","Icy","Cloudy","Windy" ,"Horrible","Damp" ,"Extra Snowy","Insalubrious" };
  Vector vWords = new Vector();
	
  public void init() {

	
    setBackground( Color.white );
    setFont (f);

    // Color the scrolling list:
    Color purple = new Color( 127, 0, 255);
   
	//store the string[] in a vector
	for (int i= 0; i< words.length; i++)
		vWords.addElement(words[i]);

	wordList = new JList(vWords);
	scrollPane = new JScrollPane(wordList);

	wordList.setBackground( purple );
    wordList.setForeground( Color.white );
    wordList.setVisibleRowCount(3);   

    // Construct a text label:
    resultstring  = "Welcome to winters in Syracuse!";
    resultlabel = new JLabel( resultstring);
	
    JPanel p = new JPanel();
	JPanel addtext = new JPanel();
	JPanel remtext = new JPanel();
	
	p.add(scrollPane);
	addtext.add(newlabel);
	addtext.add(newitemtext);
	remtext.add(oldlabel);
	remtext.add(olditemtext);

	getContentPane().add(p,"North");
    getContentPane().add(resultlabel,"South");
    getContentPane().add (addtext,"West");
    getContentPane().add (remtext,"East");
    
	// Register the applet to listen for events:
	newitemtext.addActionListener(this);    
    olditemtext.addActionListener(this);    
    wordList.addListSelectionListener( this );

  }
  

  public void valueChanged(ListSelectionEvent event)
  {
	updateLabel();
  }

  
  public void actionPerformed( ActionEvent event ) 
  { // if a textfield has been entered, determine which one:
	  
	//add to list
	 if (event.getSource() == newitemtext) 
	 {
		 vWords.addElement(newitemtext.getText());
		 newitemtext.setText (" ");
	 }

	 //remove from list
	 if (event.getSource() == olditemtext) 
	 {
	    if(vWords.removeElement(olditemtext.getText()) == false)
			olditemtext.setText ("No such item to remove!");
		else
			olditemtext.setText (" ");
	 }
	 //refresh list
	 wordList.setListData(vWords);
	 wordList.setSelectedIndex(vWords.size()-1);
     updateLabel();
  }

  
  public void updateLabel() 
  { 
  //  get the String array of the labels of selected items
    Object[] itemobj = wordList.getSelectedValues();
	String itemlabels[]=new String[itemobj.length];
	for (int i=0;i<itemobj.length;i++)
		itemlabels[i] = itemobj[i].toString();

	// Build string of comma-separated items:
    String str = "Welcome to ";
    for ( int i = 0; i < itemlabels.length; i++ ) 
        str += itemlabels[i] + ",";
    
    // Insert "and" in the appropriate place:
    if ( !str.equals( "" ) ) {
      str += " winters in Syracuse!";
      int pos = str.lastIndexOf( "," );
      if ( pos != -1 )
        str = str.substring( 0, pos )  + str.substring( pos + 1 );
    }
    resultlabel.setText( str );  // update label  
  }
  
}