content: /*
   *    This program is free software; you can redistribute it and/or modify
   *    it under the terms of the GNU General Public License as published by
   *    the Free Software Foundation; either version 2 of the License, or
   *    (at your option) any later version.
   *
   *    This program is distributed in the hope that it will be useful,
   *    but WITHOUT ANY WARRANTY; without even the implied warranty of
   *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *    GNU General Public License for more details.
   *
   *    You should have received a copy of the GNU General Public License
   *    along with this program; if not, write to the Free Software
   *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   */
  
  /*
   *    ListSelectorDialog.java
   *    Copyright (C) 1999 University of Waikato, Hamilton, New Zealand
   *
   */
  
  package weka.gui;
  
  import java.awt.BorderLayout;
  import java.awt.Container;
  import java.awt.Dimension;
  import java.awt.Frame;
  import java.awt.Toolkit;
  import java.awt.event.ActionEvent;
  import java.awt.event.ActionListener;
  import java.util.regex.Pattern;
  
  import javax.swing.Box;
  import javax.swing.BoxLayout;
  import javax.swing.DefaultListModel;
  import javax.swing.JButton;
  import javax.swing.JDialog;
  import javax.swing.JList;
  import javax.swing.JOptionPane;
  import javax.swing.JScrollPane;
  
  /** 
   * A dialog to present the user with a list of items, that the user can
   * make a selection from, or cancel the selection.
   *
   * @author Len Trigg (trigg@cs.waikato.ac.nz)
   * @version $Revision: 1.9 $
   */
  public class ListSelectorDialog
    extends JDialog {
  
    /** for serialization */
    private static final long serialVersionUID = 906147926840288895L;
    
    /** Click to choose the currently selected property */
    protected JButton m_SelectBut = new JButton("Select");
  
    /** Click to cancel the property selection */
    protected JButton m_CancelBut = new JButton("Cancel");
  
    /** Click to enter a regex pattern for selection */
    protected JButton m_PatternBut = new JButton("Pattern");
  
    /** The list component */
    protected JList m_List;
    
    /** Whether the selection was made or cancelled */
    protected int m_Result;
  
    /** Signifies an OK property selection */
    public static final int APPROVE_OPTION = 0;
  
    /** Signifies a cancelled property selection */
    public static final int CANCEL_OPTION = 1;
  
    /** The current regular expression. */
    protected String m_PatternRegEx = ".*";
    
    /**
     * Create the list selection dialog.
     *
     * @param parentFrame the parent frame of the dialog
     * @param userList the JList component the user will select from
     */
    public ListSelectorDialog(Frame parentFrame, JList userList) {
      
      super(parentFrame, "Select items", true);
      m_List = userList;
      m_CancelBut.setMnemonic('C');
      m_CancelBut.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
  	m_Result = CANCEL_OPTION;
  	setVisible(false);
        }
      });
      m_SelectBut.setMnemonic('S');
      m_SelectBut.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
  	m_Result = APPROVE_OPTION;
  	setVisible(false);
        }
      });
      m_PatternBut.setMnemonic('P');
      m_PatternBut.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
          selectPattern();
        }
      });
      
      Container c = getContentPane();
      c.setLayout(new BorderLayout());
      //    setBorder(BorderFactory.createTitledBorder("Select a property"));
      Box b1 = new Box(BoxLayout.X_AXIS);
      b1.add(m_SelectBut);
      b1.add(Box.createHorizontalStrut(10));
      b1.add(m_PatternBut);
      b1.add(Box.createHorizontalStrut(10));
      b1.add(m_CancelBut);
      c.add(b1, BorderLayout.SOUTH);
      c.add(new JScrollPane(m_List), BorderLayout.CENTER);
  
      getRootPane().setDefaultButton(m_SelectBut);
      
      pack();
  
      // make sure, it's not bigger than the screen
      Dimension screen = Toolkit.getDefaultToolkit().getScreenSize();
      int width  = getWidth() > screen.getWidth() 
                      ? (int) screen.getWidth() : getWidth();
      int height = getHeight() > screen.getHeight() 
                      ? (int) screen.getHeight() : getHeight();
      setSize(width, height);
    }
  
    /**
     * Pops up the modal dialog and waits for cancel or a selection.
     *
     * @return either APPROVE_OPTION, or CANCEL_OPTION
     */
    public int showDialog() {
  
      m_Result = CANCEL_OPTION;
      int [] origSelected = m_List.getSelectedIndices();
      setVisible(true);
      if (m_Result == CANCEL_OPTION) {
        m_List.setSelectedIndices(origSelected);
      }
      return m_Result;
    }
  
    /**
     * opens a separate dialog for entering a regex pattern for selecting
     * elements from the provided list
     */
    protected void selectPattern() {
      String pattern = JOptionPane.showInputDialog(
                          m_PatternBut.getParent(),
                          "Enter a Perl regular expression ('.*' for all)",
                          m_PatternRegEx);
      if (pattern != null) {
        try {
          Pattern.compile(pattern);
          m_PatternRegEx = pattern;
          m_List.clearSelection();
          for (int i = 0; i < m_List.getModel().getSize(); i++) {
            if (Pattern.matches(
                  pattern, m_List.getModel().getElementAt(i).toString()))
              m_List.addSelectionInterval(i, i);
          }
        }
        catch (Exception ex) {
          JOptionPane.showMessageDialog(
            m_PatternBut.getParent(),
            "'" + pattern + "' is not a valid Perl regular expression!\n" 
            + "Error: " + ex, 
            "Error in Pattern...", 
            JOptionPane.ERROR_MESSAGE);
        }
      }
    }
    
    /**
     * Tests out the list selector from the command line.
     *
     * @param args ignored
     */
    public static void main(String [] args) {
  
      try {
        DefaultListModel lm = new DefaultListModel();      
        lm.addElement("one");
        lm.addElement("two");
        lm.addElement("three");
        lm.addElement("four");
        lm.addElement("five");
        JList jl = new JList(lm);
        final ListSelectorDialog jd = new ListSelectorDialog(null, jl);
        int result = jd.showDialog();
        if (result == ListSelectorDialog.APPROVE_OPTION) {
  	System.err.println("Fields Selected");
  	int [] selected = jl.getSelectedIndices();
  	for (int i = 0; i < selected.length; i++) {
  	  System.err.println("" + selected[i]
  			     + " " + lm.elementAt(selected[i]));
  	}
        } else {
  	System.err.println("Cancelled");
        }
        System.exit(0);
      } catch (Exception ex) {
        ex.printStackTrace();
        System.err.println(ex.getMessage());
      }
    }
  }
  